Guitar Build Process

Access port cover and frame

For the cover, there will be six layers, in three pairs

• inner pair (smaller hole)

• middle pair (larger hole)

• outer pair (larger hole, outer layer Blackwood)

For the frame, there will only be four layers (two pairs)

This is because the outer layer will be the sides of the guitar

Resaw & mill tas oak stock into 2.5mm sheets
Do the same for a smaller amount of Blackwood for the outer, show layer

• mill this to 2mm, and also a vertical-grain backing layer - to equal thickness of guitar sides

While at it:

• consider milling some 2mm fingerboard-wood for pick guard and truss rod cover

• consider milling wood for 1 at the same time (1.7x9.5mm?)

Rip stock to required widths before resawing (makes laminating much easier)
Note that the measurements below are workpiece end-targets, leave stock a little wider so that trimming to final size can be done later.

All pieces 2.5mm thick
The 25mm is a minimum, 30 is OK

Cut bent stock into 560mm lengths & steam bend

moisten strips, then layer two at a time (for 25++mm widths, two lots side by side)
wrap in aluminium foil
heat with heat gun
place in mould, clamp for 5 mins
swap ends over, re-clamp (try to even out any unevenness in curve)
when cool, remove from mould, remove aluminium foil,
hold lengths in long clamp while drying

Covers

Note that the outermost layer will actually be a little wider due to the "nested" nature of the lamination.
six layers, alternating grain, two "smaller", four "larger" (outer one Blackwood)
laminate in pairs, using bass mould and matching cauls for outer pairs, guitar mould for inner
for each pair, the outer layer has lengthwise grain from bent pieces, inner upright grain from flat.

The outer "show" layer, from 2mm boards, is a little different

• may well have both pieces lengthwise grain, as per guitar sides)

• we may choose to have Jarrah border on the outermost layer,

• in this case, we should wait until it is time to fit the outer layer into the guitar body

The border process is

• wait until it is time to fit the outer layer into the guitar body

• sand the the outer layer's inner ply to fit

• cut the center piece from blackwood, leaving space for border around side

• using centre piece to balance vertically, glue in centre piece, top and bottom

• glue the side pillars

Trim to dimension/tidiness using belt sander
Then laminate inner and middle pair together:

• check curvature of laminating mould against solera mould, with any neck-join shimming in place

• tack together with thin nails for alignment,

• optional: place nails such that we can clamp around them

• otherwise: glue and clamp without moulds, clean off squeeze out,
  when confident, remove nails and clamp using moulds

• (Outer pair will be laminated later)

Frames

Dimensions:

• frames should be constructed to extend 50mm each side, and 25-30mm top and bottom

• frames will be trimmed later, final dimensions determined by guitar sides

Cut all pieces, using laminated cover for measurements

• Note that lengths on all curved pieces, and the heights on all straight/vertical pieces, can be rough

• Since the two cover pieces were trimmed on the belt sander,
  the widths of the vertical pieces will need to be adjusted.
  label these pieces to match the corresponding cover edges.
  Do all this before gluing (or there'll be some awkward chisel work)!

Laminate the individual pieces, as in access_port.docx diagram below

Notes

For tops and bottoms:

• Vertical straight layers are "behind" or "inside", on the concave side

For side pieces:

• Vertical straight layers are "in front of" or "outside", on the convex side

In every single case:

• Top & bottom have "longer curved pieces"

• Sides have "longer straight pieces"

• Don't worry about squeeze out from the frame inner edges, that can easily be sanded.

• However, do clean up squeeze out from the inner, "stepped" corners (where the shorter piece ends), as this area is a glue face in the next steps.

Clamping

• Tops and bottoms: can be clamped "as is", as vertical-grain pieces are "thin". However, the access port moulds (and matching cauls) can be used if desired.

• Sides: used pairs of small curved cauls, ideally *just* short of the curved-grain widths

Assemble each layer using cover as template,

• Separate layers, sand all surfaces so that joins are "flat"

• Hold assembled (with covers in place) and trim roughly

• Do not glue frame layers together

Drill holes in cover and frame

Use regular drill press, Dremel has some vibration issues
1/8" bolts - will use brass nuts and bolts
Using aluminium corner-hole guide, drill first in corners of port cover, from outside inwards

use a sharp drill bit
3mm holes, centres about 6mm in from edges
back with some 13mm scrap on drill platform to get curved surface horizontal

Then drill holes in back layer (of frame) using cover to guide drill (press all layers together)

back with a suitably-thick strip of scrap, to raise workpiece so it hole is level, and also provide clean exit hole

Cut two nut-strips of wood, 4x15

position so they overhang the opening by about 3-4mm
this will support the quite close-to-the-edge hole in the inner layer

Drill 3mm holes in the nut strips, matching those on each side of the port
Enlarge these holes to 5.5mm, but only halfway through (ie, 2mm), on the surface that will be glued to the inside of the frame
Hammer nuts into these holes, so that they are flush with the surface
These are to hold the nuts so they will neither twist, nor be pushed forwards when screwing in access port cover
Do not glue yet - final step requires sides to be completed

Neck block & tongue assembly

In the following discussion

• The term "receiver" refers to the neck block, specifically with respect to its engineered (rather than cut) mortise.

• The term "neck tongue" refers to a piece that will eventually be glued into the heel, thereby becoming a tenon

Resaw and mill 19 x 65mm tas oak stock into 8mm stock

two boards can be got from one length

Cross-ply laminate to form receiver backing plate (will need two side-ply pieces butted together)

Trim square after dry

Rip 19mm thickness stock into three pieces per guitar, will form the "receiver" of the neck tongue
NB: each of these measurements are after trimming - can make some of them larger and trim/cleanup

Glue to the cross-grained face of the laminate block,
in the shape of a "U", with the thick piece on the right.
Use the base & thin upright to ensure the channel is perfectly square to the laminated block

• slower-but-better: glue it in three steps, bottom, thin, then thick

Use some 19mm waste as a spacer while gluing
Trim/clean up on table saw, round-over the show face (thick upright side)

Neck join tongues
Resaw & mill some 65mm width stock to 5mm and 9mm thickness boards (perhaps even 4 & 11mm)

two outer layers, grain lengthwise (up & down), 5mm thick
one inner layer, grain sideways (ie inline with as neck), 9mm, will have to butt-join (don't bother with 75/80/110mm wide stock)
laminate, trim, thickness to 19mm using holding channel jig and drum sander if required (minor adjustments can be done using belt sander)

Check tongue fit into neck block

NB: Label each side of tongue top/bottom/neck/body
NB: leave some space at the bottom, for vertical adjustability

Choose nuts (need to be set into tongues)

and bolts (need to be 60mm long, and possibly trimmed later
I chose M6 60mm Allen-headed bolts & matching 5mm deep nuts
That means the holes need to be 6mm diameter

Use centering jig to drill two holes in backing plate

• measure 15mm from each end of tongue

• with tongue centred vertically, mark positions in receiver channel (leave space above and below for adjustment)

• a centering jig is a piece of 19mm stock with pilot hole dead centre

• insert into receiver, drill holes through pilot hole into backing plate

fit tongue, use holes in backing plate to drill starter holes in tongue
remove tongue from block, finish holes in tongue,

using squaring jig to keep the holes as straight as possible (ie, exit in the centre of the tongue)

Option #1

• Bolts are for clamping neck to body, not intended to remain in work

• Tidy slots are acceptable aesthetically

• Otherwise, consider how to hide/finish off holes after bolts are removed (access will be restricted)

• cover strip? channels?

Option #2

• Bolts remain in work, useful if tongue requires lots of shimming...

• Optionally make an easy-to-fit cover strip (access will be limited, as it will need to be fitted inside the body)

• Glue side strips so that centre can be friction-fitted tightly enough to allow glue to cure?

Drill 10mm deep 10mm diam counter-holes in the exit (neck)

• Force-fit two nuts into 10mm holes, so they are flush

• Note: the inner nut is the only one that will apply tension, the outer is just to prevent it from being knocked forward

• Clamp tongue to avoid splitting

• Thread one bolt 25mm onto the nut

• Use the bolt as a centering guide to hammer the nut into the 10mm hole

• Once the nut is just beneath the surface, tap it out, thread the second nut just nestling, not locked, and hammer them both all the way in

• Check that the bolts can engage with the nut from the other (body) side

To facilitate fitting the neck, there is one more step

• vertically elongate the two holes in the neck block, 2mm top and bottom
  very carefully use laminate trimmer/router (low revs), with fence attached to face
  This will allow the tongue to slide up and down, and tightened at the correct height

Controlling the router to get tidy slots is difficult, options include

• enlarge the holes using a drill first, so that the router can spin freely on startup

• before locking the fence, spin the router backwards so that it nudges the work until there is no engagement

• use a smaller router bit

Tentative steps for a bolt-on neck

* construct neck block and neck-tongue as per regualar glued neck, with two exceptions

(a) the top bolt-hole needs to be 12mm lower
(b) don't do the round-over on the wide edge

• prepare fingerboard-support components, specifically the 9x14 fork prongs,
  a 19x14 inner piece, and two 9x14 wings

• The 14/15mm thickness is for soundboard & soundboard angle, and will be thinned down when fitting neck

• Cut off top 11mm of neck block!

• Position neck tongue, sticking up

• Prepare padding and fingerboard frame pieces, 11mm deep,
  leaving an (initially bottomless) pocket 46x{extension}mm

• Glue padding and frame together, including the 5mm tray bottom

• (Check that top neck-tongue bolts can still be fitted)

• Trim the sides so they align with match the neck block, this will mean cutting away 10mm from the cutaway side

• Mill some timber to 5mm for the triangular reinforcing side strut-plates

• Cut a 5mm triangular support channel into the non-cutaway side of the block

• Cut a trapezoid channel on the cutaway side, in just the part beneath the tray underside

• In both cases, start at about the midway point between the two bolt holes, up to the end of the underside of the tray

• Since the cutaway side is less supported, add a 5mm triangle inside, and a 3mm covering triangle on the outside

• Glue the triangular strut-places in flush in place,
  angling the grain so that it is parallel with the hypotenuse

• Proceed with build steps until it is time to fit neck

Truss rod (if not using a bought one)

NB: Regular acoustic guitar truss rod is too long for my GP model

there is not enough room for neck-tongue slot!!!
Therefore, can only use bought truss rods for bass
(as nothing available in parlor size)

Make Martin-style truss rods as per this video

https://www.youtube.com/watch?v=ysKRHdIaaEg

with some changes

use a furniture bolt "socket" nut instead of T-nut
12*12mm channel
M6 threads
3/16" / M5 washers (small diameter, they fit M6 threaded rod)

Lengths

Socket nut flange 2mm thick
coupler/barrel bolt 18mm
M6 hex head nut head depth 6mm
washer <1mm
nut 6mm
need 25mm clearance from body-fret (for neck tongue channel)
want to limit hex nut to ~15mm past nut, so truss rod cover can work
also want truss rod to end near zero-fret, where neck depth is deeper due to volute
Therefore, coupler/barrel bolt best cut down to 15mm.

Equation is therefore

take body-fret position (eg 345.1 for 24.5" scale, 14th body fret)
-25mm (neck-body clearance)
-2mm (socket nut flange)
-0.5mm (washer)
This is the aluminium channel length (318 in the above case)
Cut/grind coupler/barrel bolt to 15mm
Threaded rod should be this length +8mm (will be trimmed later) (326 in the above case)

Method

cut threaded rod & aluminium channel to length
cut/grind coupler/barrel bolt to 15mm
grind a 12x12mm square nut so that it friction fits in the middle of the U-channel, so tensioned threaded rod pushes against it for more bowing
fit regular M6 nut - the torque nut
fit furniture socket nut - the end nut
tighten them against each other
grind the sides of the torque nut square, with three facets flush with the furniture nut shaft
the rod, nut torque nut and end nut shaft should fit snug into the aluminium channel
weld the torque nut to the rod, then re-grind so it's square again
cut socket bolt, leaving about 7mm of free coupler thread
fit socket bolt to coupler
cut notch into coupler, up against socket bolt head
put a bead of weld in the notch to join the two together
grind the weld pretty
temporarily insert a long bolt into the coupler/end-nut
grind off the coupler facets manually, then put temporary bolt into hand drill, and hold it against grinder while spinning, to form a cylinder/bullet shape.
Finally use drill press as a "lathe" with sandpaper to polish it.
grind off the tops of the threads above the inserted square nut if required, so nothing extends past top of U-channel

U-channel

cut 3mm slots 17mm from each end (into the "top" of the U)
scribe a line 10mm from the U-bottom
grind/cut/file/sand between the notches, so the U is 10mm high (notches now mark "flaps")
insert threaded rod one end
bend over the flaps at each end (vice)
grind off the portions of end-nut flange that protrude, leaving a squared end

NB: important

• the threaded rod is only approxomately the length we need

• if it is left too long, the truss rod adjustment nut will bottom out

• remember (and check) that our adjustment nut has about 8mm of usable thread

• thread a dummy nut, cut rod to exact size, remove nut so thread is useable

washer, wax/oil
spray with water dispersant
assemble & test
when adequately oiled, seal open side of channel with masking tape, and trim so channel sides are not covered

Neck, headstock & heel

Cutting necks

Headstock scarf angle ~14deg = 19 rise over 75 run, slope = 0.248, angle = 14.2, hypotenuse = 77.4
The table below takes into account...

• kerf losses (in combination with 14-degree angle)

• heastock veneer

• heastock section initially thicker to leave enough "meat" for the volute

Stock width: 65mm

Scarf joint table

"Scarf cut start" measured from heel-end, scarf cut will end approx 75mm further towards nut/headstock.

Heel pieces

Cut from same piece as neck, and adjacent to body-end of neck stock

Rough lengths: 125/95/90, 65, 55, 50, 45, 40

Cut heel and neck/headstock pieces, labelling each piece so that stacking the heel pieces can be done so that exposed end-grain aligns
Use well-rested quarter-sawn 65*19
Label so that any bow is *upward*, we don't want any back-bow baked into the neck

(fretboard will tend to produce more backbow, and we want to let the truss rod take care of it).

Cut scarf joint using jig on table saw

Aim for kerf to be evenly spaced around scribed hypotenuse line
Clean up wedge-ends by stacking so that hypotenuses align and sanding
NB: do this before drum-sanding the neck piece.
Get rid of any uneven saw grooves, blade-burn, and make sure each wedge-edge is straight and square

Mill neck stock down to 16.5mm

But not the headstock piece, which we need to be thicker, so that it can "slide down the fretboard" by about 12mm, to give "meat" for volute
Mill the "shallow wedge angle" side, not the sharp one (which would shorten the piece)

Align scarf joint using scarf joint clamping jig

This will prevent two problems

• It stops the two wedge pieces from being pushed apart when clamped

• If keeps the neck and headstock piece co-linear, ie prevents rotation

Glue up & clamp

If headstock piece is not perfectly aligned with neck piece

(This was more a problem before using the clamping jig)
After gluing, mark a true centreline along the headstock, taking account of any rotation if the headstock piece was not perfectly aligned with the neck piece.
Use masking tape to shim sides of the headstock (or trim using table saw), so that they are parallel to this line
This is necessary as the headstock sides run along the router fench when cutting reinforcing spline channel.
Any headstock non-alignment may also affect cutting the truss rod channel.

Use the heel alignment hole jig to drill 9.5mm holes in the heel pieces, then use a bolt when gluing them up

• It will help the pieces stay aligned, and not slide when clamped

• It will also assist with clamping (although additional clamps are still required)

Glue up heel pieces, making sure the grain lines up, but don't attach heel to neck yet
Clean up the upper face and sides of the headstock, perfectly flat, straight & square

Reinforcing spline

Cut a channel along headstock, 8mm deep, about 18mm wide,

"bevelling off" into the neck (see diagram below)
use router table
channel should be aligned with neck (if any rotation in scarf joint)
always feed the piece right-to-left to avoid router pulling it away from fence

Mill and glue in spline, then level with sander, sandpaper etc.

Cut truss rod channel (12mm wide, 10mm deep) using router table

NB: do this before attaching headstock wings!

Headstock wings

Before attaching headstock wings

• Rip headstock piece to 50mm wide (balanced around centre)

• This will place the two heastock wing join lines "inside" the headstock, avoiding them appearing along the headstock sides (where the angle is acute, making them more obvious)

• It does however make for a lot of tricky re-jointering...

Rip some 19mm stock, cut to headstock length-20mm:

Don't make them any wider than they need to be, thinner = more flex = more forgiving of imperfectly-jointered surfaces.
(Trim width to about 20mm or less, keep offcuts for side braces later?)
Rough-up the outer (dressed) sides (or clean up the ripped faces), and glue to headstock,

starting around 20mm from top neck-headstock vertex.
Make sure TOP faces are aligned (wings will be 3mm thinner than headstock, due to padding)

Trim headstock ends square - NB: square to NECK, if scarf joint rotated a bit!

Thinning headstock, also forming volute curve

Rewmove dust shroud from drum sander
Slide headstock under sander drum, find end-position to leave volute "end" curve
- make a mark on the neck, 27mm from the inside scarf joint line (don't press too hard, pencil lines can dig into the neck)
- using a square, position this mark under the "start" of the drum
On the sander outlet end, clamp a stop piece at the position of the (squared) headstock end
Jack up drum sander dust shroud with ~32mm offcuts (clamp them for security)
Thickness headstock to <12mm (depending on the headstock veneer), pushing the headstock under the drum, against the stop piece, then out again
Turn the neck around, move the stop piece, and give the lightest dressing to the underside,
- just "kissing" the scarf joint

Headstock veneer

Resaw & mill Blackwood and Celery-top Pine to <2.5mm, laminate

Show layer is Blackwood, the pine is to provide a contrast stripe around the outside
Aligning the pine layer cross-ply may strengthen the headstock wing joints, however it also causes three issues:

• it may render the piece curved, causing problens when thinning in the drum sander

• when sanding the wedge, the bulk of the work must be done after gluing it to the headstock, as the lower layer has edge-aligned grain

• when trimming the sides of thinning the neck, pull out is an issue as part of the top of the neck has sideways grain

Recommendation: don't do it
If the result has some curvature, moisten, heat and clamp to remove it - this can cause uneven thinning in the drum sander

Pantograph router, avoiding disaster

clamp pantograph to upper right corner of router table
use wrapped stylus, so no play in template channels
clamp work-holder jig "underneath" that, perfectly square
clamp template 200mm from bottom left, with piece of 19mm stock for stylus "rest spot"

template should be pretty square to table

see image below
put mill bit in Dremel as far in as it goes
make sure the chuck is tight!!!
make sure workpiece has headstock outline, logo position and most importantly, centre line marked

draw cross-line 40mm under the top wave-motif line - that will be base of "M"

soft-clamp the workpiece in the work-holder jig

hover stylus above M-middle-bottom, move workpiece so mill bit is on crossline-centerline intersection
make sure *centerline* of workpiece is square to holder jig (and therefore, table top), screw down wingnut clamps

rout the inlay, "hovering" the stylus at first, then all the way in
make sure to go back-and-forth on all three M-feet.

Mix some clear glass sparkle, turquoise glass sparkle and fine green glitter in a mini bowl
Fill the routed channels with glitter mix, to just under the top

- should be able to scrape an edger over without dislodging any

Apply a few drops of low-viscosity CA glue to partially fix the glitter in place
Mix a capful each of epoxy resin and hardener in a plastic cup (or cut off plastic bottle, whatever)
Drizzle the resin in careful not to drag the glitter around (CA glue should reduce this risk)

- make sure it covers each edge

Butane flame or heat gun to de-bubble

heat gun underneath to encourage resin to ooze down into channel
more butane flame to get rid of additional bubbles

Carefully drum sand the veneer, first to reveal clean filled channels

then (front & back) to get down to 4mm.

If drum sanding pulled out any pieces of glitter

fill with CA glue (may require more than one application) then level with fine sandpaper

Reestablish the centreline, using the centre pillar of the "M"

Retrace the headstock shape (onto the veneer) from the template, aligning with the centreline

Important: find the centreline at the far end of the headstock

Beware: if scarf joint is not perfectly square, more care is needed to find correct centreline
Transfer line so it is the same front and back

NB: in the following steps, 16mm is assumed to be the run of a 14-degree wedge of 4mm thick veneer

if the veneer is thicker or thinner, adjust to match

Trace two more lines onto the headstock veneer:

transverse line for the back of the nut,
and a parallel line 16mm forward (towards neck/body) of that
cut along this line

Mark a line on the headstock 16mm back from the scarf joint - this will be the back of the nut.

Plan for truss rod adjustment nut to extend 14mm further past the end of the nut

The aim is for the end of the truss rod to be underneath the thickest part of the volute
Drill a 9mm hole in the veneer 20mm past the end of the nut (4mm past planned end of truss rod nut)
Cut a slot up to the hole on the bandsaw

With the bandsaw, trim away some of the veneer waste around the nut-to-wings flare
With the belt sander, cut off about 80% of the "upward sloping" edge of the veneer,

making a bevel, coplanar with the top of the neck.

Glue veneer to headstock aligning previously drawn centrelines

two small nails can be used to prevent slippage while clamping
use cauls to even out pressure since the veneer is thin

Finish veneer bevel with sandpaper and/or scraper, making a perfectly flat and flush transition to neck
Finish truss rod adjustment nut slot with rat-tail file, to allow hex key access

The slot will coplanar with the neck, bevel "up and out" of the headstock

Now is a good time to check for any neck-bow - remove by sanding and/or clamping

Continuing the neck

If pursuing bolt-on neck experiment

• Mark body-fret line on neck

• Mark neck-end of truss rod (notes immediately below)

• Using router, widen & deepen truss rod channel at heel end to accept fingerboard support "prongs"

• 13mm deep, 37mm wide, extend to end of truss rod

• Wood will be 16mm thick, that will leave 3mm at bottom of neck piece

• Don't bother squaring them off, fitting the fingerboard support needs to be done later

Position truss rod so the end of the adjustment hex-nut extends 14mm past the back of the nut

Note that this corresponds to the aluminium section lines up with the fingerboard, and ends at the start of the nut.
We want the truss rod adjustment hex barrel to "just" protude up through the headstock veneer,
while the end of the truss needs to be above the extra thickness provided by the volute

The truss rod will have two deeper sections at each end (where the flaps are folded)

Use a chisel to carefully deepen the corresponding sections of the channel

If not done yet, put some masking tape over the open channel of the truss rod, trim sides flush
Mix some Araldite, spread some on the sides only of the truss rod channels

glue truss rod in place, if slightly low in the channel that's ok (not high)

If the truss rod is low in the channel

Rip 12mm lengths of very thin timber, glue over truss rod

Scrape/sand everything flush
Using the headstock template, clearly mark & square the position of the *back* of the nut

If all has gone well, this should be *just* inside the newly-sanded/exposed neck-headstock break

Mark a (squared) line 6mm down-neck from this - this is the fretboard/nut boundary.

Now we can mark the body fret line

Now we can plan neck width profile

Mark centreline at body-fret, then *centred* body-fret neck width

Mark *centred* nut neck width

Rule in neck edge cut-lines

trace in headstock-neck transition lines (make them symmetric)

Take already-glued-together heel block stacks

If drawing a line on the underside of the neck, don't press too hard, pencil can dig in
Bottom of stack will be ~45mm
Bottom of heel will be 35mm
Glue & clamp, with about 5mm spare each end

Transfer neck edge cut lines (width lines) to the underside of neck

NB: heel block may not be square - use set-square

Transfer headstock outline to back of headstock:

Cannot cut headstock shape right way up due to headstock angle
This will be hard to get 100% accurate, when we cut it out (later) we'll leave plenty of space so that it can be finished on the belt sander with frequent checking of the front.

Use this diagram to rough-in heel curve.

This is a very rough guide

• Measure 45mm down from the underside of the neck piece

• Measure 33mm in from the bodyline heel cut

• Measure 30mm in from the bottom of the heel

• Trace a quarter circle from that point to the underside of the neck piece

• Extend the bottom part of the curve to 30mm in from the bottom of the heel

Rough the shape in on the bandsaw, then get closer on the belt sander
Cut the body-join line on the bandsaw using the mitre

Be careful that the heel block might not be quite square

Clamp neck to mitre, making sure that everything is square

Now we can cut the neck to width on the bandsaw, leaving about 1mm to sand down accurately

• Start the process - shallow vertical lines along the heel - on the table saw

• Then do the neck side lines, starting with those groove-cuts

Carving the neck shape - facet method, assume 16-17mm neck thickness,
Aiming for a nice "C" shape

• first facets 15mm into the back, 10mm up the sides of the neck, flaring to 15mm at the heel

• This will leave 6mm of vertical timber each side of the top of the neck

• Second facets 4+4 (moving out from fretboard) and 6+6 (along the inside towards middle) - two of each

• This will leave 2mm of vertical timber each side

• Note that this seems "too much". but our neck is wider than it will eventually be...!

"flare" facets outward around volute and inward at the headstock - don't overthink it, it's pretty easy.
Smooth remaining facets, sand out rasp lines

Use Shinto saw rasp for straight sections, curved rasp for heel curve

Remove some of the scratches with a regular wood file

After cutting the three sets of facets, round everything over with a wood file

Coarse sandpaper to move closer to finished surface

Around this time, re-transfer & cut headstock shape (leaving 2mm extra) using bandsaw & belt sander.

Fingerboard

Mill Merbau / Jarrah / Spotted Gum to 6.5mm, 66mm wide

Rough cut lengths

Rough in radius using drum-sander sloping jig

Draw scribble lines all over the surfsace
Make two sets of passes through the drum sander, rotating the work lengthwise
We want the two bevels, each being about a third of the width wide
The pencil scribbles allow the depth of cut to be judged accurately

Finish radius with 11" radius sanding block

Sides philosophy

Since kiln-dried timber is more readily available (and therefore, more choices with respect to grain, quarter-sawn, etc), we have chosen to go with it.
Kiln-dried timber is however much harder to steam-bend, and therefore needs to be milled to ~2mm
That's extremely thin at the best of time, but our steam bending process (with Tasmanian Blackwood, at least) of that thickness leades to lateral waviness
We therefore use a laminating process, to get adequate robustness, and allow sanding out the waves.
Originally I used plain old pine for the inner layer, but I've switched to Macrocarpa

Milling sides stock

Mill to: 2mm (two sheets per side, to laminate to 4mm)

Those measurements assume near-perfect placement in the bender, allow a little more if unsure

Side bending

Assume

mould is in Fox bender with lower bout to the left
if there is a colour gradient across the side stock, we prefer darker toward guitar back

Then

Non-cutaway side: Darker side is to the rear
Cutaway side: Darker side is to the front

NB: New aluminium foil each time! Four layers on wide pieces (bass)

Aluiminium foil stops steam from escaping, and protects against iron contamination (from shim-stock in bender, and filings from when we made the truss rod). Iron reacts with hot, steamy timber and stains it irretrievably black.
Laminate each pair backwards, so blackwood "show" side is protected by what will be the inner layer

Shim stock process

Steel shim stock protects the timber by evening out bending stresses and heat
Under the wood: one layer of aluminium flashing, sprayed with black engine enamel, to better absorb heat lamp energy.
Aluminium is also bendier, less springy, plasing less stress on the bent sides when removing from mould
Following that: one layer of 1/100th" steel shim stock
Over the wood: two layers of steel shim stock, but the outer one only over the waist and cutaway area

Heat top shims with heat gun while operating the Fox bender.
Order of operation:

Tighten waist press screw to keep mould and work steady
Make sure work is parallel with sides of mould
Measure so that the work piece will extend about 40mm past the end of the bottom of the mould's lower bout
For all the following steps, play the heat gun over the exposed top shim stock, to help heat the workpiece
Bend down the lower bout, keep it in place with the spring clamp
Bend down the upper bout, keep it in place with spring clamp and/or cutaway press screw
Slowly tighten waist press screw
If making cutaway sides, even more slowly tighten cutaway press screw
Leave work in the bender with lamps on for about 5 minutes, then let them cool down for about 45 minutes.
After removing them, allow each piece to dry thoroughly before next steps
Consider clamping them in the laminating mould to dry, to reduce springback

Also

Do the bindings while the Fox bender is set up

Two-layer, same colour

Milled hardwood 9.5x1.7mm - make sure all edges are clean
Update: intend to experiment with less-deep bindings to reduce tilt-gap problem (see bindings step, below)

n-layer with accent colour on the inside

See bindings step, below

Make sure grain is straight along the bend dimension
4x each side

Side Lamination

Place side pairs in laminating moulds, and trim off excess that otherwide prevent moulds from standing on workbench
Laminate pairs in laminating moulds
Radical decision: use Polyurethane glue!

fills gaps due to inadequate clamping
(Aliphatic glues, ie Titebond, produce voids, even with the best clamping)

Procedure

Put masking along sides of both mould and clamping caul, extending sideways
Apply glue sparingly!!!
It is critically important that the sides are perfectly aligned with the mould, clamping tight from one end to the other can cause this to "creep in".
Loosely fit all clamps, check alignment, then tighen
Note that the masking tape may make this problem harder to see
Too much squeeze-out makes extraction from mould tricky (hence masking tape)
If any squeeze-out has gotten onto mould, remove from mould *approximately* after three hours (depending on weather/temperature),

while glue is soft enough to separate easily,
but inside the lamination, strong enough to hold

NB: if taking the sides out of the mould early, put the cutaway side back in afterwards, and reclamp
- tight - so that there won't be any spring-back due to soft glue (which then hardens, cementing the wrong shape!)

Fitting sides to solera mould

• finalise neck-width at body-fret, create shim between solera mould-halves so cutaway-edge-to-centre is half that
  Do not skip this step - solera moulds are a little thin on the neck join

• even better, glue permanent shims for the standard neck width, so that we only have to shim for 12-string (or 5-string, in the case of bass)

Fitting sides into solera mould is tricky, follow these steps carefully

• Manually estimate cutaway end, as it will not fit into mould until near-perfect

• Cut outside that estimate, fit inside and see how much needs to be trimmed so cutaway curve matches solera as closely as possible

• Again, cut slightly less than that, repeat until satisfactory

• Fit both pieces inside their respective half of the solera mould

• Mark how far the tail each end extends

• Cut 5mm short of that line

• Attempt to clamp the two halves of the solera mould together

• The tail will be out by about 10mm, mark how much needs to come off each side

• Cut slightly less than that off and reclamp

• The neck end will be way out, measure the gap between the two neck-ends of the solera mould

• Cut that much minus 5mm from the non-cutaway side

• Reclamp, check if solera mould can clamp together tightly

• Also check verticality of sides around perimeter

• Keep cutting a little at a time until perfect

• A misaligned centreline at the tail end is quite OK, it will be hidden by tail strip and access port cover

• Depending on how secure the fit is, out-pressing turnbuckle clamps may be needed while cutting front and back profiles, and gluing access-port frame and neck block

Trim top of sides to create soundboard edge

if sides are loose, consider gluing a temporary joiner piece to the place where the access port will be cut out
Spokeshave time

• use laminated MDF reference flat surface

• raise frame slightly and evenly

• make sure every point along the sides are vertical (use set square)

• slide a pencil around the inside perimeter, drawing a line

• shave and plane to that line to get a perfectly flat top edge

• edge can be checked with MDF reference surface

• sticking sandpaper to MDF surface with double-sided sticky tape can zero in final flattening

• (Though this can wait until after the kerfed lining)

Trim bottom of sides to create curved back profile

Invert, mark dimensions for cuved back

With standard heights of Bass: 150, GP: 115 and Parlour: 108, that means

take care around cutaway - height *increases* towards centre!

• two-dimensional curve

• longitudinal curve governed by curved sanding stick

• lateral curve much less than sanding stick curve,

• lateral curve near cutaway with shorter, shallower sanding stick

• This can be roughed in, and finessed later (after kerfed linings attached) with curved sanding sticks

• If a well-shaped result is achieved while still too high, keep it - it is much easier to cut down the flat topside to the correct size

• Turn work over to check "roll" of edges against flat surface

• Avoid any "sharp" spots (tilt rather than roll), they will make fitting bindings more difficult

• In paricular, the measurements above have a sharp spot in the middle that is intended to be rounded over

Gluing neck block

Mark the two angled bevels that need to be cut
One on bottom, to fit into curved back - flat OK at first
One at the side, to fit into cutaway - will need to be sanded concave

• Use the narrow convex sanding block to match the shape of the inner cutaway

NB: neck width at body fret needs to be considered

need centre of tongue-channel to be 0.5*neck width from outside of cutaway face

(see table above)

For bolt-on neck option

• a lot more material needs to be removed

• a lot more shaping is required

• on the cutaway side, start with the bandsaw to get a vertal line

• smooth that cut with the band sander, taking care to keep the lines straight and square

• fine-tune curve with radiused sanding block

• there is a larger surface area to be glued to the cutaway curve, it needs to be tight all around

• consider using double-sided tape to stick sandpaper to the inside of the guitar cutaway, and sand the neck block against that

NB: Double check that sides (especially around shoulder/cutaway) are square to the front. Gluing the neck block commits to the that alignment.
Glue and clamp

Gluing access port

Assemble all layers together (two sets not glued), cover screwed in place (for alignment)

• NB: cover can't be in place if "temporary joiner piece" glued at seam

Position, centre vertically and horizontally, mark layers, trim leaving ~1mm top and bottom
Glue outer piece, so that the extra 1mm is evenly distributed top and bottom

• clamp the outer ends with same convex clamping cauls used when laminating access port frame upright components

Don't bother sanding it flush yet, wait for the kerfed linings.

Mark true centre, top and bottom, tail and neck
Remove from mould!

(possible thanks to over-engineered sides and single access port frame layer)

Cut ~2mm deep slot (dado style on table saw), then cut and fit tail strip

(much harder to do later, after we cut the actual hole)
Also, end-tear-out is less of a problem now

(Surface tear out can be managed by decent blade and/or slow feed speed)

Centre over true centreline (might not be sides join-line)
Before finalising width, put back in solera to check alignment
Glue in, then trim and level
It is quite acceptable to cut the tail strip in two so that it just covers top and bottom, as the access port hole is about to be cut out

Using drill, hole-saw and router(flush bearing bit), remove material from hole

Drill and hole-saw: remove the bulk so the router does less work
Router: flush bearing bit to rout sides to line of access port outer layer

Remove any glue on access port sides first, so routed line is straight

Square out corners with rectangular file so cover fits through

a regular rectangular fire, while slower than some alternatives, is safer:
Make a notch in the rounded corner, then work it outward and downward until both edges are straight.

The end result if this step is that the cover should fit through (and sink into) the hole, so that it is flush with the inside (ie, to its final depth)

The steps involved include

• Making sure the outide hole perimeter is straight, square and it true corners

• Fitting the cover in as best as possible, then putting your head inside the guitar, looking in a light source, and noting tight spots

• Drawing lines with a pencil to show when you are filing parallel to hole edges

• At the very end of the process, it might be appropriate to sand the cover itself, particularly to adjust the angles the two ends

Fit inner layer (using partially completed cover to align)
Mark sanded/trimmed top & bottom line, trim
Holes drilled yet?
Glue and clamp inner layer,

• fit cover (including bolts) to ensure the two layers align

• note that some of the inner layer face does NOT require glue!!!

• use frame-to-sides clamping caul with exact shallow curve at each side of the frame

• remove cover immediately so it won't get stuck by glue squeeze out

Problem of inner layer springback

Clamping outside solera mould may change tail curve
Access port cover curve may no longer match access port frame

Current procedure

After gluing in the middly layer, inspect:

• The resulting curve of the sides+middle layer

• The curve of the as-yet-not-glued-in inner layer

• The curve of the cover

Take remedial actions as required:

• Relax or tighten curvature of middle layer before gluing by wetting, heading, clamping

• Relax or tighten curvature of cover (wet / heat gun, clamping)

• Consdier whether the laminating moulds need to be remade/adjusted before laminating in the first place

Also, consider

• just how different is the curve?

• Will it still fit into the solera?

• Remember cover will be bolted in place, inside solera when attaching back and soundboard

• Will the difference in tail curve be noticeable when the guitar is complete?

Previous approach (not recommended, not shown in images)

• rub some candle-wax around inside of cover

• rub some candle-wax around non-glued surfaces of frame

• leave cover in place while clamping

Finish access port

Prepare the following

• outermost layer (actual show piece), ~1.7mm, curved

• second-outermost layer, <2mm, also curved

• some strips of border accent wood, ~12 x 2mm, straight

To create the outermost lamination

• Carefully trim/sand second-outermost so that it fits into the hole,
  OK if it doesn't quite go all the way in against the cover

• Cut border strips with the top and bottom pieces full width and the uprights fitting between them

• Cut the outer centre panel so that it fits between the border strips

• Use sacrificial backing, as tear out affects the show face

• Glue and clamp top and bottom strips and centre panel

• The cover can act as a clamping mould for this step, since the top and bottom border strips are not pre-curved

• When dry, excavate any squeeze out from the channel where the side border strips are to go

• Glue and clamp the side border strips

• sand the border strips flush(ish)

• redo the fitting, as perimeter will have changed...

This almost final perimeter fit

• trim to within ~0.5mm on table saw, cutting "inwards" to prevent tearout

• sand top and bottom so that the piece fits

• for each side, slide up, inspect gap - there will be some unevenness

• sand out until each end slides up perfectly

• check overall width, reduce and reprofile appropriate side-end as needed

Before proceeding, check that inner cover curve matches guitar

• if it is too shallow, consider shimming the two side edges

• if it is too deep, consider shaving down the two side edges

• also consider wetting / heat gun / clamping to adjust curve

At this stage, it may turn out that the cover doesn't sink in as far as it should

• This may lead to the outer layer being too proud, and requiring too much levelling

• Especially if the two outer layers are too thick

• Consider very gently sanding the outside of the cover, to thin it a little

• Don't overdo it, glue squeeze out on the cover show face (panel, border) will require some levelling

Tack two thin nails through inner cover, poking outwards 2mm

Angle (relative to the curve) so they're parallel with each other (not flaring out)!

Fit inner cover
Press outer cover layer into place, impaling it against the two nails
Remove
Laminate outer layer, using nails as index for alignment

• if at all possible, remove as much squeeze out, as sanding/scraping/chiselling it from a fit-critical edge is not much fun

Remove nails

Extend five holes (strap button in middle, four countersunk screw holes at corners)
Fit cover in place
Screw four corner bolts through holes (apply some candle-wax first)
Glue in place the two nut-strips we made when laminating access port layers

Best done with cover in place, but need to manage squeeze out
Rub some candle-wax around inner edges of cover
Apply glue to inner face of nut-strips (if possible, not the parts exposed at the edge)
Position nut-strips in place
Tighten four bolts so they engage nuts and extend inwards
Clamp (bolts are only pulling against nuts, nut-strips are just sitting over them)

Hopefully end up with cover fitting, as well as the four bolts
Scrape and sand flush if any major level discrepancy (lots of further sanding to be done later)

Clearly mark centre lines on side frame

both ends, top and bottom, glue faces, inside, outside
I mean, it's so annoying when you have to keep working it out again...

Kerfed lining

19mm stock, rip and mill to 7mm, the put a radius on one of the side edges
Bandsaw guide - slotted stop board,
use headless nail to get each cut "evenly" spaced lol
Also use bandsaw table extender
Cut and glue in place, top & back, clamping with washing clamps (see image)
NB: for inside the cutaway horn section, the kerfs will need to be widened with a file, beveling the blocks so they can pack closer together
Using the Shinto (not band-sander!) trim to a whisker above already-prepared top and bottom profiles, then sand by hand to get perfect surface for gluing

Resawing, milling, butt-joining back and soundboard

Raw minimum dimensions (cut longer and wider for jointing and positioning leeway)

both pieces, both sides
Mill timber to 5mm
Resawing on the bandsaw - use resaw post, lock the fence down proper!
NB: pay special attention to drum sander scarring: particularly if using 60-grit sandpaper.

If perfectly parallel to the grain it can be overlooked, but with any lateral movement in the drum sander it becomes an eyesore that is very difficult to sand out, particularly on the soundboard.
A combination of 80 grit, plus some final low-friction passes on the show face, should be enough to keep it under control.

NB: if not butt-joining immediately, store boards clamped between two flat boards to prevent bowing/cupping

If necessary, joint the edges with jointer fence on router, although that can have tearout issues.
Preferred method: use aluminium angle jointer sanding jig.

Butt-join using a sheet of MDF, nailed down strips of pine as edge stops

• Cover MDF with oven paper where join line will be

• Raise the two pieces along the join line with a piece of 19x42mm stock

• Position and nail down edge stops

• Apply glue, align, then remove the length of stock and press down

• Check joint alignment, cover with more oven paper and weight

NB: after butt-joining, store boards clamped between two flat boards to prevent bowing

When dry, using mould, trace body shape outline, cut with bandsaw, 5-20mm outside line

• Leave flat sections at each end, so they can be pushed through drum sander with a piece of 3mm MDF

Mill to required thickness using drum sander

• First mill non-show faces so that join line is clean and smooth

• Then mill show faces so that join line is clean and smooth

• Finally mill non-show faces (again) to width

• Soundboard:
  Celery-top: 2.8mm
  Huon Pine: 3.0mm
  King Billy: 3.4mm

• Back: 3.5mm

Clearly mark centre lines

Bracing and fitting back and soundboard

Prepare (rip, resaw and mill) back-brace sizes and positions

Four,
two x 8*16mm (vertical taper, neck end)
two x 12*19mm (rounded over, tail end)

Spacing (from neck)

While thus tooled up, might as well mill stock for side braces as well

8x5mm, long enough for eight x body height

Prepare A-frame soundboard braces size and positions

Two pieces, 8*19 (vertical taper)

from neck joint to a spread at tail of

2 * 8*17..19 wing braces (rounded over) (outside of bridge to side)

Sanding profiles into braces

Rough-in the profile with belt sander
Use a holding jig to avoid stressing fingers

Make a small number of jigs with set-length adjustments (bolts screwing down)
Handles to hold easily and press while sanding

Clamp sandpaper to moulds, sand until full profile is cut (no flat spots)
If using the pinch handles, be very careful not to rock the pieces

Use the handles to apply back-and-forth pressure,
letting the pieces stay "seated" at all times

Planning back brace positions and gluing

Method 1: (preferred) regular clamps at ends, caul blocks & go-bar clamps in middle
Method 2: (shown) caul blocks and go-bar clamp at ends first, clean up squeeze-out, then do middle
Enhancement: make two forked alignment guides that can be clamped to the edge, to prevent the pieces from wandering during before clamping is complete

Preparing and fitting centre-strips

Cut five lengths of milled 3-4mm cross-grain hardwood
30-40mm wide
NB: the outer two cannot be glued yet (length depends on neck block and access port)

• The reason we glue the inner three pieces now instead of later is simply to make the back stronger during the next few steps

Round over edges, glue the inner three down centreline of back
Use go-bar clamps, same rods as for back braces (with 19mm cauls)

Tapering back braces

Spokeshave, plane, chisel, short block of scrap to check straight lines

Originally

Tail end pair: 50mm linear taper down to 2mm at perimeter
Neck end pair: 65mm linear taper down to 2mm at perimeter

Amended

taper down to 1mm, so that notches in sides can be covered by 7mm bindings instead of 9mm

Planning and gluing soundboard brace positions

Trickier
Put side frame in mould, with turnbuckle bracing if required
Trace out neck-block, cutaway-kerfed lining, access port positions - to the inside of the soundboard
Mark how A-frame braces need to trimmed to fit (and do so)
Glue: normal clamps at ends, go-bar clamps in middle as per when gluing back braces

Tapering soundboard A-frame braces

Taper full-scale line to neck,

then from 19mm tail-ward of that line to tail
(ie around the wing braces)
aim for 2mm at ends

Scalloping: about 5mm dip midway, both ends

Preparing soundboard bridge plate

Body-fret to full-scale line

Mark bridge-line (full scale length)
Bass bridge is 52mm deep, guitars less than 50

- let's just say 50 for all

Cut 3mm bridge plate, 75mm deep (will trim later)

Cross-ply
Sand in a bit of a lateral crown to match dip in mould

(to reduce the bracing contours appearing when the soundboard is varnished)

Starting 7mm in front of bridge line, total depth = bridge_depth+10

60++ is probably about right

wedged between A-frame braces

Trim depth after getting the wedge angle right

Soundboard hole and neck-end support

Both: cross-ply for additional strength
Soundboard hole support: 2-3mm hardwood (can be multiple pieces)
hole support: bout to waist, board can be slipped under sides for tracing
For this operation, soundboard should "fit" against mould-encased side frame,
(which should already be traced on the inside of the soundboard)
Neck-end support: 4mm hardwood (back trimmings OK, can be multiple pieces)
Laminated below fingerboard on body, nestled in the top of the "A"

Taper soundboard wing braces

cut bevel (optional compound / two-dimensional) so they sit against A-braces
They sit against the tail-ward side of the full scale line, straight out
Sand tiniest possible curve on bottom, then taper from top
Down to 2mm
Straight at first, then optionally with tiny scalloping

Glue in bridge plate, hole support, neck-end support and wing braces

Wing braces aligned with the 19mm full-height section of A-frame braces
Go-bar clamps/deck

Preparing to fit back to sides

NB: fit sides into solera mould, it makes subtle differences to where we need to cut channels for the braces
Place access port cover in the hole (to support clamping)

will need to drill tail strap-button hole if not done already so that cover can be pulled out afterwards
put temporary 1/8" bolt & nut, protruding outwards as "puller"

Sides are in mould, turn-buckle clamps if required so no gaps
While "rolling" the back over the sides, mark where the braces meet the sides

Before cutting, fill in the kerfs around the marked positions with pine shavings and polyurethane glue
Try to have the filling just go down 5mm, so that the kerfs will look natural through the soundhole,
The idea is that the kerfs stop just before the bit that is to be cut away
This will prevent linings from crumbling when cutting channels

Now it is time to start cutting the channels

Start at one end, making sure both ends are centred
One brace at a time
Double-check position and alignment at every step
Cut brace channels too narrow, then check, then widen
Sand out incorrect pencil marks to avoid confusion

Cut small channels using small pull-saw, chisel and file

With the pull-saw, make two edge cuts,

make them too narrow at first - better to file outwards than have gaps
then two shallow wedge cuts to meet them,
then chisel out the "hill" in between
finally use chisel, file and sandpaper to create the "downward" ramps into the body
check position at each step

Adjust so that back can curve over sides, into place
NB: finish centre-strips at this stage

Trace neck block and access port edges onto inside of back
cut the final two centre strips to fit, glue them in and confirm that everything still fits

Preparing to fit soundboard to sides

Same deal - cut shallow channels for wing braces

Cut and fit vertical side braces

Takes sides out of frame for easier clamping
rip some hardwood 8x5mm
Same positions as back braces (slots in kerfed lining)
Cut to fit between kerfed linings
15mm taper to 2mm top and bottom

(dimensions not critical)

Cut and fit support backing for pickup socket

• use some spare curved hardwood stock (leftovers from access port?)

Cut and fit support backing for neck strap button

• Cut a piece of hardwood about 55x55x10mm

• Cut or sand to match curve "above" neck block

• Nestle between curfed lining, and against neck block

Glue back to sides

Back in frame with turnbuckles if required
Attach "rudder" to neck block, make sure it is perfectly square to centreline
Go-bar deck & rods with split-cushion cauls to distribute force

(avoid uneven joins, gaps)

Do a full dry clamp-up first, to check that all join-lines are tight.

• if the end centre strip pieces are too long, the back can be glued properly at each end, but leave gaps around the cutaway area

Glue soundboard to sides

NB: make sure the sides are square, so that the guitar can sit stable on its sides
Use wedged sticks if required,

to push top part of sides against mould
can't have turnbuckle clamps in mould when gluing top!
less force will be required, as final shape is fixed by glued-in bottom
we're only "tilting" the sides to their final shape at top
Go-bar deck & rods with split-cushion cauls to distribute force

Another thing to consider:

• since the guitar is resting on its curved back, excessive force
  when fitting soundboard may cause the sides to warp slightly

• consider supporting the sides (with pieces of varying thickness)

Trim overhang carefully with flush-bearing router

• **Climb-cut everything that's "flat"***

• **For the rest, always go "downhill" (towards centreline)

Tear-out is a risk, especially if the bit is dull

(though small tear-outs will be covered by binding)

Make multiple 2mm climb-cut passes
Don't worry about 1-2mm overhang on back, due to curved back

it will be taken care of when cutting binding channels

Trace, cut and smooth soundhole

Trace outline using template as a guide

Positioning

• outside of hole follows 25mm inside upper bout edge

• inside of hole approaches fretboard by about 25mm (more for bass)

• inside of hole forms a smooth curve with lower bout (below the waist)

• that curve involves a slight angle between the straight sections of each side (hole, bout)

• template may not be 100% accurate to achieve this

(Originally used Dremel with downmill)
Large diameter Forstner bit for initial hole, then small router, then Dremel with mini drum sander
then finish with sandpaper wrapped around PVC pipes of various diameters
Very slight roundover around the hole - large roundovers are harder to French polish

Rout (or cut with table saw) a vertical channel along the cutaway-neck "corner"

Decide on design

Wider strip (show face at side) = best "enclosed" by bindings
Narrower strip = bindings can butt up against it

(in which case defer until after attaching bindings)

10x3mm is OK, so is 2*2mm

• Do not exceed 3mm "thick" - the channel depth must not extend beyond the binding channel!

Cut the strip and channel now, so that any tear-out will be removed when routing binding channels
We will glue the strip in after gluing the bindings
Use same wood as for bindings

For softer soundboards (especially Huon Pine)

Fit a soundboard protector for much of the rest of the build. It is so easy to scratch and dent!

From now on

• Guitar body needs to rest on a towel to prevent scratches and dents

Before routing the binding channels

• Check the sides for any waviness, and level them by aggressive sanding and scraping.

• If not done so already, level access port cover at this time too

• Seal a strip 25mm each side of the bindings edges with shellac (except heel-join area)
  This is to prevent glue squeezeout from soaking in, which is otherwise discovered when French polishing, and has to be aggressively sanded back

Doing these steps after attaching the bindings risks having to scrape the bindings too far back, leaving uneven thickness.

Rout binding channels

Sharpen router bit first!
Rout to 3.5mm inward depth, 8-9mm downward depth
Use router with vertial sliding jig and rabbet bit w. bearing
NB: take care at the neck/cutaway corner - do not round it over! Keep it square!
NB: also, makeabsolutely sure the guitar body is straight and secured in the cradle, so the channels are perfectly vertical!
NB: also, check that the router is cutting channels to the full (sideways) depth - make sure the sides are against the roller bearing, and measure depth to confirm 3mm all around

Direction of cuts

• Any cuts along slopes - cut "downwards", (ie, towards waist, towards centre)

• Any other cuts - climb-cut

• After everything is done, go around again in the regular push-cut direction to tidy things up

Tips for building jig

Similar to StewMac vertical sliding jig
use two drawer runners, wheels aligned back-to-front
the assembly turned out a bit heaver (hello over-engineering!), so I used a bungy cord to make it easier to use
for the "donut" to allow the jig to "ride" the sloping back edges, I used multiple layers of Perspex Araldited together

Rough-cut neck-tongue pocket

This must be done after the binding channels are cut, or there will be problems near the heel cap!
Open up a hole in edge with pull-saw
Use flush-cut router bit

Glue in the vertical boundary strip along the cutaway-neck "corner"
(Strip and channel cut two steps earlier)
Scrape and sand flush (neck-facing side)
Leave a bit proud on the side-of-body side

(So that we can scape/sand flush after attaching the neck)

trim each end flush with the binding channels

Attaching bindings

There is a problem with wooden bindings on a curved-back guitar,
and I have yet to perfect a solution. If using two layers of the
same type of timber the problem is less severe, as the gaps can be
filled and are quite hard to see under shellac. However if using
different timers for an accent strip, the gaps are far more serious,
as they cause the accent layer to visibly wander towards the edge.

Principles to solve this problem

• make sure curved back profile is smooth, with no "sharp" bends

• choose less-deep bindings, eg 7mm instead of 9mm

• channels need to be perfectly vertical: make sure guitar is secure in cradle when cutting bindings channels so it doesn't tilt over

• thinner inner layers conform more easily (outermost layer still needs to be a bit thicker)

• file/sand tilt-bevels on inside surface at waist, upper bout, horn and cutaway so tilted binding presents a vertical face to glue

• do at least one dry tape-up to test that tilt-bevels are adequate before gluing

There are currently two choices for bindings

• Two same-colour layers of 7.5x1.7mm

• Having the inner layer(s) in an accent colour

For accent layers, current recommendations

Soundboard side

• Lighter-coloured soundboard makes a three-layer plan more appealing

• No curvature means far less risk of gaps around waist & cutaway

• Inner layer: dark, 0.6mm

• Middle layer: light: 0.6mm (more??)

• Outer layer: dark, 1.8mm

Rounded back

• Darker-coloured back makes a two-layer plan more appealing

• Curvature means we need to file/sand in some tilt bevels at the waist, upper bout, horn and cutaway

• However, if the inner layer is thick enough for those bevels, any gaps will mean we need to pare back the correspondingly-thinner outer layer, not only making the problem very obvious, but also raising the risk of sanding through the outer layer!

• Current working notes...

• Inner layer: light, 0.8mm

• Middle layer: dark, 0.6mm

• Outer layer: dark, 1.4mm (more??)

Important: to reduce tilting of bindings due to curved back

• sand away 0.25mm-1mm tilt bevels of lower-inner corners of bindings

• at waist

• at upper bout (non-cutaway side)

• at cutaway outer curve ("horn")

• at cutaway inner curve

Fine-tuning tilt-bevels

• It is essential to perform at least two dry tape-ups to ensure there are no gaps.

Clamping method

• do it in four stages

• cradle body in half of the solera jig

• use elastic clamping jig

NB: note that in some of the images below, I have used the clamping jng backwards.
This is OK for a small-bodied guitar, but ideally the jig should be the right way round, as shown in the first image.

Scrape bindings flush

The more overhang, the more work!

For the soundboard and back

For the ends that extand up/down past the bottom and soundboard, using a spokeshave can remove material quickly
However, great care must be taken not to dig in, and because there are two layers of binding, this means that some sections cannot be trimmed this way.
The scraper is also susceptible to grain direction, but less seriously.
Spokeshave, then scraper, then sandpaper.

For the sides

Wrap the Shinto saw-rasp tip with two layers of masking tape
Hold it by the tip so we can use pull-strokes
The masking tape protects the sides from being scratched
Use this for coarse material removal
Scraping the Shinto longituninally along the bindings can weaken the timber, making subsequent filing/sanding easier
After the Shinto, sandpaper
After sandpaper, the scraper with a fresh burr!

Shallac Test

Apply more shellac around the joins, this serves two purposes:

• to reveal any glue that needs more sanding,

• to reveal any scratches from the Shinto... that need more sanding

• it is much better to do this now that after starting French polishing

If the bindings have an accent layer

File a small notch at the heel-cutaway 90-degree join, where the accent layer buts onto the heel
This void can then be filled with darker putty, giving a concentric or nested appearance
See photos below

Fill any major voids in body

Ignore gaps smaller than those to be dealt with when grain-filling
Find them all
Glue and sawdust, or coloured hard-setting putty

Glue and sawdust is difficult to remove later...

Very annoying to keep finding one more when it's time for finishing
Sand adequately (important if using glue and sawdust, or shellac will reveal pale spots)

Making a fret-position template for the StewMac jig

• Create a table of fret-positions, as well as between-fret distances for double checking

• StewMac website has a good calculator for this

• Use custom jig to hold large (60mm) calipers and length of alumium bar

• Slide calipers to fret positions, scribe line along jaw using compass point

• Use second (normal size) pair of calipers to double check inter-fret distances to avoid "off-by-one" errors

• Use bandsaw to cut slots, with sliding bevel and a piece of masking tape to line up the scribed lines

• (Alternatively, a micro table saw with a thin carbide blade can do this more accurately)

• For some scale-lengths, the final few frets will have to be cut "from the other end"

• Either re-scribe those lines using caliper jig, or carefully transfer using set square

• When cutting "from other end", don't forget that the slots must be one the other side of the scribed line!

• Clean up slots with files / hacksaw blades / sandpaper wrapped around scraper (or other thin piece of metal)

Plan fretboard fret count and width

Width extension ratios (of positions of fret pairs)

6-string / 14-body-fret: 21 frets

12-string / 12-body-fret: 19 frets

Bass / 14 body fret: 19 frets

Slotting fingerboards for frets

Use jig & template

Check after slotting 0th fret (doesn't matter if it's not right, we're going to cut all the way through on that one)

Trim fingerboard to width

3mm MDF strip, double-sided sticky tape, bandsaw fence
use 3mm MDF strip, slightly wider than fingerboard
attach fingerboard to strip with double-sided tape
rotate so that cut-line is parallel to one side, slightly "in" from edge
setup bandsaw with fine blade
use bandsaw fence strips slides along
MDF sacrificial backing also prevents tear-out
repeat for other edge
Finish both edges using aluminium straight-edge bar

and double-sided tape-attached sandpaper

Finalise wave motif on fretboard

Freehand draw, rough cut with bandsaw,
progress with belt sander,
finish tight radius with sandpaper wrapped around PVC pipe

Widen all fret slots

Very easily done now
This will reduce the amount of hammering, especially onto an unsupported area of the fretboard
Start by scoring with a compass point
Finish by tapping in a piece of fret wire with the barbs removed
(Alternative: using a fret press in the drill press)

Fretboard inlay and side dots

Drizzle super-thin CA to fix

Inlay dots

Forstner bit (using stop-nuts on the drill press to get accurate depths)
To drill the 12th-fret pair without resetting the stop-nuts, shim the edge with a ruler, and don't quite bottom out.
12th-fret pair: edge 5-8mm from fretboard edge = centre 9-12mm from edge

• Having them not quite perfectly centred is OK

• Leaving a bit more spare width at the bottom edge

• Which we may need to remove when levelling the cutaway-heel join

Try to have them 100% flush, to minimise sanding them level
a little CA on top is OK
having to sand them flat is also OK (400)
if hole too deep, shim with little circles of paper - though this can make them sit unsteady
a little sawdust in the holes might be a good idea

Side dots

Dremel drill press with 2mm drill bit and aluminium side-dot jig
12th-fret pair: about 10-12mm spacing

Finalise neck carving, now we have fingerboard to size

trace fingerboard onto top of neck
lots of fiddly work
scraper useful
coordinate neck width with body (but leave a little bit proud both sides if possible)
finalise headstock shape with spindle of belt sander

Make index pins for fretboard

cut the heads off two small nails, leaving 11mm and 15mm
nail them into top of neck, short one near nut, longer one near heel
leave 3mm sticking out
file those stumps to sharp points with a file
impale the fretboard over the indexing spikes, hammer/clamp if needed

Progress trimming neck to fit fretboard

concentrate on the top side
leave some material to be removed on the lower side (cutaway)
(This will make cutting the neck-tongue slot a bit easier)
Also finish the neck-headstock transition now that the fretboard is in place

Drill tuner holes in headstock

My choice of tuners

clamp drilled headstock template to headstock
get a nail, wrap with masking tape if diameter not correct
poke through template holes to make marks in headstock
Drill holes with Forstner bit (against sacrificial base)

• Set drill press stop nuts so that the Forstner bit spike just pokes into the base

• The hole stops about 1mm before the other side

• Turn piece around and finish from the back, using the hole the spike made to guide the bit

• This give perfectly clean holes on both sides

Hole diameter

Fitting neck to body

Estimate neck angle

• Ideally, the heel face will be cut perfectly square

• Ideally, the soundboard will have a slight curve due to the curved A-frame bracing

• Ideally, the neck block will be perfectly perpendicular

• Ideally, we want a perfectly straight line across the junction of the neck and soundboard

• The curved soundboard will fall away from this line, contributing to the bridge height

• Therefore, we will need to sand a slight angle into the heel face

• Line up the neck with the body to get a rough estimate of the required angle

• Sand almost that estimated angle into the heel face using band sander, the tidy it up with a strip of sandpaper attached to a board

• This will also dress the face, which will be rough from being cut on the bandsaw

• Take care not to crown it

Cut slot in heel for neck-tongue

Use table saw in dado mode, being very careful not to make it too loose
Depth: so that there is about 1-2mm of space when tongue is fitted

(Measure tongue extenstion from neck-block assembly in body)
(Be careful not to hit the steel end-nut of the truss rod)

Position (lateral): very careful,

we have already almost finished trimming the top side of neck & fretboard
we will be sanding cutaway portion of neck and body flush

After cutting slot, lower portion of heel will be very fragile

It will be held together by about ~7mm of edgewise grain
Consider gluing a temporary piece of scrap over the end to support it (will be trimmed later when fitting the heel cap)

Preparing to fit neck to body

Neck tongue should now fit into body and neck
Fit to body, use M6 60mm furniture screws, screwed in all the way

Fit neck, check three alignments

• Side-to-side (yaw) angle - are the three centres (tail, neck-join, nut) in line?

• Up-and-down (pitch) angle - zero in on the neck angle previously estimated, we want a perfectly straight line where the fretboard spans the neck and body
  Note that since the soundboard is slightly curved, there will be a small amount of "fall away" at the highest frets.

• Rotational (roll) angle - does the "roll" axis neck align with the body?

Fix the first two by sanding the butt-end of the neck
Fix the third by shaving and shimming the neck tongue (remove from body)
Mark correct height of neck-tongue in neck slot

(there is +/- 2mm of play due to the neck-block slots, so mark the centre position)

Now that we know more about the join, so a little bit more on the bottom side of the neck if required
We want to minimise the amount of neck to remove once fretboard is attached

Especially around the heel

Use neck tongue and do as much as possible on the heel-cutaway join

but leave a tiny bit of the vertical boundary strip proud so that we can sand it smooth after joining

Plan and partially cut heel cap

Option (a) (preferred)

trim heel to an angle matching curved back
heel cap will be even thickness
when gluing on fretboard, temporarily attach a wedge (nails?)
to make a flat surface on the end of the heel to make clamping easier

Option (b)

leave heel straight, heel cap will be a wedge
in this case, clamping is simple when gluing on fretboard

In both cases, plan for it to be flush with back

But leave it proud for now
Don't attach yet

Glue neck-tongue into neck

Use the neck-height mark made two steps up

(doesn't have to be exact, due to the +/- 2mm of play)

Leave two furniture bolts in the tongue, to prevent glue getting into nut threads

Trim the tips off if there is not enough room when fully screwed in
(when doing a dry fit)

Tongue fit should be not too firm, glue will take up space and also swell the wood
Clamping is hard, be careful if you clamp the heel that it doesn't "angle out"
Some side clamping is good, but not too tight, don't want to split the grain
Clean off all squeeze out

Take note of the thickness of the thickness of the backing plate

• This will needed to trim the clamping bolts to correct length when attaching the neck

Glue neck to body

Determine correct length and trim furniture bolts for clamping

• They need to engage with embedded nuts, but not extend further tro presse against heel

Use furniture bolts to clamp, but make sure neck height is right before tightening
Clean of all squeeze out very carefully
Decide whether to remove furniture bolts when dry

• the slots are probably better aesthetically

• but there's no harm in leaving them in place (though it might give the incorrect impression that the neck is removable)

Attend to any coarse levelling required at neck-cutaway join

(will finalise it in the next step)
sand down any remaining proud amount of vertical boundary strip

Temporarily attach fretboard to neck

• Since we're following the Finish soundboard first option, just press it down onto the index pins for alignment.
  Use clamps if the index pins don't have enough friction to keep it secure

Ensure neck and body under fretboard is ruler-flat
This may require minor sanding, in which case the index pins should be removed (and replaced afterwards)
Heel is either still flat, or has temporary angled block screwed on to make clamping heel area easier

Finalise fretboard, neck and heel fit

• Some cleanup will still be required after fretboard is glued on.

• Mark the centreline / fullscale line point

• Extend that line outwards to string-spacing width at bridge

• Use two rulers to extend the fretboard edges, checking that they symmetrically "bracket" this line

• Level heel-cutaway transition

• Depending on how perfectly the heel joins the body, levelling might "eat into" the side of the fretboard

• If it's less than 0.5mm that's OK, at this stage there is usually about that much "extra"

• Remove it and re-flatten that edge against aluminium section sanding bar

• re-check symmetry, we don't want the centreline to wander (<1mm is OK)

• sand and scrape so fretboard-neck join is near-perfect, which will leave a fragile sharp edge after fingerboard is removed...

Attach a short, bevelled surrogate fretboard to neck to protect the fragile, newly-created sharp edges

• have it stop just short of the body-fret (so it won't interfere when French polishing soundboard)

• also, bevelled down to an edge at that end (same reason)

• a little overhang at each side

• screwed into the top of the neck

• all the handling will round over those sharp edges, resulting in a gap along the fingerboard-neck join line

Making bridge

Decide on bridge blank thickness

Mark full-scale line on soundboard

Ensure frets are flat (er, what frets?)
Use ruler to find height of bridge blank (expect 9-10mm)

• Note: the standard method is to use a ruler on top of the frets...
  But we don't have any frets yet!
  So... run the ruler along the (fretless) fretboard,
  and since my choice of frets is ~1.2mm high, add approximately 1.2mm.

Cut and mill blank : 152 x 50mm x required depth
Cutting saddle slot with table saw

current blade cuts 2.6mm slots
good for "thin" saddles, and can be widened with two passes
centre saddle blank in slot, fill remaining slot space with strips of wood

Alternative method: laminated bridge

• Top layer: 4mm, two pieces with gap for slot

• (Could even consider multuple layers, allowing for an accent colour...)

• Bottom layer(s): whatever is needed for chosen bridge height

• Care will be needed when thinning down the wings: don't sand through top layer!

Planning compensation (cutting saddle slot)
Option #1: cutting the slot into a one-piece bridge using the table saw

Depth of slot = 4mm

assume 152mm of blank, length and all-the-way through slot method

6-string guitars, ~55mm string spacing at saddle

compensation is x..x+3
scaled from string spacing to bridge blank length: x..x+8.3
cut 8.3mm shim
position so that slot edge is

• ~8mm at low E~

• ~5mm at high E (3mm difference)

Bass guitars, ~58mm string spacing at saddle

compensation is x..x+4
scaled from string spacing to bridge blank length: x..x+7.7
cut 7.7mm shim
position so that slot edge is

• ~9mm at low E

• ~5mm at high G (4mm difference)

12-string guitars, ~60mm string spacing at saddle

compensation is x...x+2 (especially if carving individual relief ramps)
scaled from string spacing to bridge blank length: x..x+5.1
cut 5.1mm shim
position so that slot edge is

• ~7mm at low E end

• ~5mm at high E end (2mm difference)

Option #2: making the slot on a laminated bridge by using two top-layer pieces

Laminate and mill the bottom layer to required thickness (x-4mm)
Mill the top layer to 4mm (corresponding to saddle slot depth)
Mill a strip of timber to the same thickness as saddle to make the two slot-infills at each end
Short version:

• use template to cut top piece in two at a shallow angle

• laminate using a candlewax-covered saddle blank and a slotted clamping caul

• remove saddle blank after about an hour

• carefully clean all squeeze-out from inside of slot

Further details to consult when planning / making template
6-string guitars, ~55mm string spacing at saddle

compensation is x..x+3
scaled from string spacing to bridge blank length: x..x+8.3
Draw a line representing the inner slot edge that is

• ~8mm at low E~

• ~5mm at high E (3mm difference)

Cut along that line
laminate the two pieces using a saddle blank to govern spacing
fill the two ends of the slot with strips of wood same thickness as saddle

Plan string spacing (Saddle)

6-string

• pins parallel to saddle

• 12mm back from slot edge

Bass

• pins parallel to saddle

• 17mm back from slot edge

12-string

from spreadsheet (string_spacing.xls)
60.2 outer string spacing at saddle

• First row 8mm back from low-E bridge slot edge

• Second row 20mm back from low-E bridge slot edge

Hole diameters

Drilling bridge pin holes using a template

• dead easy, drill holes being careful not to enlarge template holes

• very slight counter sink for bridge pin shoulders

• (See diameter table above)

Bridge pin holes if not using a template

• Mark positions using compass point

• Then pilot hole punch

• Drill in Dremel drill press, 3mm bit, 3mm deep
  Position by hand with power off, hold down, drill

• Use countersink bit to widen shallow holes
  so larger drill bit will seat correctly

• see diameter table above

• very slight counter sink for bridge pin shoulders

Shape bridge

Cut/sand outline, then thin down wings
Scallop line 1: from bass-side slot end to wave point (will taper "in" a bit)
Scallop line 2: mirror of scallop line 1
Top taper: draw a line about 9mm in from the top wave profile

Scallop underside of bridge

Concave transverse bow matching (and slightly exceeding) bow in soundboard
Then also a "cavity" scallop
Reason: so that we can clamp using bolts through the bridge pin holes

The complex concave curves will serve two purposes

• "pull" the soundboard into a slight convex shape

• Have "sharper" join-lines around the perimeter

Plan bridge placement

Find and mark lateral placement first

• lay a metre rule along each side of the fretboard

• should be ~2mm outside of the outer bridge pin holes

• equalised = centred laterally

Use StewMac Saddlematic for lengthwise placement

• Wait a minute - we have no frets!

Preferred option

• take a length of fretwire (doesn't even need to be radiused)

• file off the barbs

• hammer into the 12th fret slot

• remove later

Option shown in image

• hammer in the 12th fret preemptively

Adjust bridge slot spikes/screws

choose compensation amounts for low and high strings
set pin width to bridge string spacing
subtract half of saddle thickness

Bass

• String spacing at saddle: 58

• Compensation 3.2..7.2

• Saddle width 3, so subtract 1.5

• Offsets from full scale to inner saddle edge: 1.7, 5.7

• Final measurements should be (for 34" scale)
  863.6 + 1.7 = 865.3
  863.6 + 5.7 = 869.3
  (Worrying that this will not be enough if the action is adequately high)

6-string

• String spacing at saddle: 55

• Compensation 2.3..5.3

• Saddle width 2.5, so subtract 1.25

• Offsets from full scale to inner saddle edge: 1.1, 4.1

• Final measurements should be (for 25.5" scale)
  647.7 + 1.1 = 648.75
  647.7 + 4.1 = 651.75

• for 24.75" scale
  628.7 + 1.1 = 629.8
  628.7 + 4.1 = 632.8

12-string

• String spacing at saddle: 60

• Compensation 2.25..4.25

• Saddle width 3.5, so subtract 1.75

• Offsets from full scale to inner saddle edge: 0.5, 2.5

• (Cannot get StewMac pins that close, consider using outer edge)

• Final measurements should be (for 25.5" scale)
  647.7 + 0.5 = 648.2
  647.7 + 2.5 = 650.2

• for 24.75" scale
  628.7 + 0.5 = 629.2
  628.7 + 2.5 = 631.2

Drill bridge pin holes in body

• Put a layer of masking tape down so we can trace bridge position with pencil

• Position bridge and trace around perimeter with a sharp pencil (can draw on Scotch tape)

• Overlay a modest amount of double-sided tape

• Note: the aim of the tape is to keep the bridge steady while we attach the C-clamps.
  The aim of the C-clamps is to keep the bridge steady while disturbing it with the drill.
  Then we need to remove the bridge without damaging the soundboard.
  This has proved tricky in the past, which is why we now do this step earlier.

• Place some upside-down fibreglass-reinforced tape near ends, to assist when removing the bridge.

• Position bridge in the exact position of the traced outline and press down.
  Use the peeled off wax paper to fine tune position before sliding it away and pressing down

• Attach and tighten the C-clamps

• Using an imperial drill bit just smaller than the bridge holes as a punch,
  make starter indentations by tapping gently while rotating the bit between hits.
  For guitar (5mm bridge holes), use a 3/16" bit
  For bass (8mm bridge holes), use a 5/16" bit

• Using that same bit, drill starter indentations only in the two innermost holes
  The C-clamps mean we cannot drill any other holes
  The slightly smaller drill bit minimises the risk of the bridge moving.

• Important: change drill bit to smaller (body) diameter!

• Remove the C-clamps, finish drilling the innermost holes, holding some scrap underneath for a clean exit-wound.

• Bolt down the bridge with 3/16" countersunk bolts (top) and wingnuts (underneath)
  BN: don't over-tighten, or there'll be mismatched counter-sinking to fix!

• Drill (and optionallu bolt) the next-innermost holes (each bolt reduces the risk of the bridge moving)

• Finally drill the outermost holes

• Optional: check using actual bridge pins, which holes are accurate enough to repeat exact positioning of bridge later

French polishing soundboard

Sand soundboard to final finish-ready smoothness
Round-over bindings (soundboard side)
Decide whether grain filling is to be done

If using grain-filling

• Position bridge, mask bridge and fretboard with magic tape (as per details in following sections)

• Apply grain filler

• Remove mask, sand filler down to wood

If feeling on a roll, do back and sides as well, though stay away from heel-cap area

Mask bridge position & fretboard for French polishing

Reposition bridge

• try just using bridge pins

• double-check with position with rulers

Put strips of Scotch/magic/invisible stickytape where bridge will be

But first, put a piece of paper down in the middle - to make removal easier when French polishing is complete
fold over ends of tape- starting a peel is difficult
since Scotch tape lifts fibres when peeled off, don't rub it down hard

Position bridge

trace around bridge perimeter with a sharp pencil (can draw on Scotch tape)
NB: on softer soundboards like Huon pine, the pencil will score the timber through the tape.

• try an additional layer of paper attached with double-sided tape.

cut straight lines and easy curves around bridge with sharp cutter

Consider variation from previous builds

• cut about 0.5-1.0mm inside the bridge outline

• shellac remains rough in sticky tape edge's lee

• use a combination of freehand, non-scratching straightedge and bridge template

peel away excess tape, leaving bridge area masked
make sure tape is firmly attached (ok to rub down now, this area will be covered by bridge)

Repeat steps for area of fretboard that is over body

Historical note

Before the Finish soundboard first option, at this stage we would

• simply mask entire fretboard

French polish soundboard first (following the Finish soundboard first option)

• NB: make sure rubber surface is clean - fresh cloth recommended

• French polish the soundboard only - long uninterrupted strokes for the win

• NB: sticky tape in the two masks may become lose and shed flakes of shellac, which then adhere to the guitar and need to be sanded down (1200 sandpaper & oil)

• See French polising notes below

• Stop before "spiriting off" stage, wait until finishing rest of guitar

• When complete, leave on all tape masking for now

Complete all construction steps deferred due to the Finish soundboard first option

Make truss rod cover and pickguard (if required)

Truss rod cover may need to have an indentation in the bottom singe truss rod nut pokes up a bit

• Initial design was a simple ogival arch

• I now have a more complex narrower design that can be removed while the strings are tensioned up

Mill some fingerboard/bridge wood

Truss rod cover

Truss rod nut almost certainl protrudes above headstock
Mill to required width - contour if thick to avoid interfering with strings
Drill / excavate a furrow in the underside, for truss rod nut to fit into
Cut a 14-degree under-bevel so it buts up nicely with the back of the nut

Pickguard

Rip to 70mm (GP), 65mm (parlour), (generally don't do bass)
Mill to 2.5mm

Shape, sand, fill grain with Timbermate or Feast Watson sanding sealer, sand

Glue fretboard to neck

NB: do a dry run clamping first, to check for any gaps
Remove fretboard tape masking from soundboard
Everybody on the internet keeps glue off the truss rod,

• This makes sense for exposed-rod designs

• It makes no sense at all for the Martin enclosed channel model

• A small piece over the truss rod nut might be a good idea though

Use inverse radius dual-curved clamping caul, it makes it a breeze
Clean off all squeeze-out carefully with moist cloth or kitchen wipe
NB: use more clamps than in image below

Attend to any minor sanding of the fretboard-neck join

• Most of the fitting was done earlier, we're really just finessing the glue joins

• Finalise smoothing the heel-cutaway transition

Attach heel cap

Clamp with a regular clamp and semicircle-cutout clamping caul with bungy cord
Finish carving still-proud transition to back and heel

Final sanding, rounding over bindings, void-and-grain-fillings

Final check for gaps - fill with glue and appropriate sawdust (or other product)

Grain-filling

• Timbermate water-based filler - various colours - diluted with water
  - works-ish, but balance between under- and over-sanding is very fine

• Feast Watson sanding sealer?
  - works-ish, but leaves some unfilled micro-voids. Over-sanded?

Installing frets

My fretwire choices

Important

• Before installing frets, tape two pieces of cardboard
  to the body where the fretboard is glued to it.

• Do not rely on masking tape, even multiple layers.

• When snipping fret ends, the pieces will fly off with great force,
  chipping the soundboard wood (or the finished surface).

• Make sure the cardboard is sealed around all edges,
  to prevent metal filings from finding their way underneath.

Radius sanding block says 11" (from 22" cymbal),

better to bend frets to a tighter radius(ie, 16" cymbal or 14" snare)
I hgave also tried a 10" radius, but hammering approach must be different (see below)

Bending wheel is not perfectly even, keep removing fretwire

and reinserting with crank at different clock positions

No

• Aggressive tightening

Yes

• Multiple passes at different clock positions

• Turning fretwire end-on-end each pass

• Each pass goes all the way (piece comes out of machine each time)

After cutting fretwire into lengths

• dull any sharp edges, so as not to cut fingers while hammering

Fret slots are too tight

StuMac recommends against widening them,

promoting a barb-shaving device

I got good results by dragging a compass spike along them

it doesn't remove wood, just stretches the slot
BUT... be very careful it doesn't jump out of the slot and scratch the fretboard!

Ben from Crimson Custom Guitars uses a triangular file

Hammering works best with a radiused, hardwood, end-grain caul

Tap one end in, not fully
Work towards middle,
Then other end
Then use hammering caul to get it fully seated
NB: if using 10" radius, start at one end, then middle, then other end

Use adjustable support strut when hammering on body
Use rockers to make sure each fret is perfectly seated along its length
The use of glue on virgin slots (widened or otherwise) is debated

I have tried several ways of using CA, without satisfaction
My preferred method is to spread a small amount of some Titebond over the open slot

• Using a fret press (more suitable to solidbodies or pre-attached fretboards) is ideal

• Using a hammer a bot more messy, however cleanup is very easy (damp cloth)

• Indeed, spatter can indicate incompletely seated frets

Snip off fret ends

• Just in case the cardboard is not adequate, rest scraper against edge of fretboard for extra protection.

File fret ends vertically level using vertical file-holder jig with bevel

• NB: ensure bevel sits on frets, so that file stays perfectly vertical
  and doesn't cut into side of fretboard

• be very careful not to slip and mark frets or sides of fretboard

File 35 degree bevel using 35 degree jig

• be very careful not to slip and mark frets

Check that the fret tops are perfectly level

• While filing the ends, any vertical bumps indicate high frets

• In some cases, imperfectly seated frets can be fixed with the fretting hammer

• In others, the aluminium sanding bar, with very fine grit sandpaper, will be needed

• If sanding has been done, re-crown the affected frets with crowning file

Finish fret ends by rounding over with fret end dressing file
Polish them and clean everything up with very fine steel wool

French polish rest of guitar

Remove access port cover, deepen countersink holes for screws if sanding has left them too shallow (annoying to do this after French polishing it)
Tape off fretboard with masking tape

leave a little bit (~2mm) of the fretboard exposed
(at least, the section that is over the neck)
this will allow the shellac-lemon-oil transition to be more easily sanded down

Decide what do about filling grain

Two-pound cut

50g flakes, 200ml methylated spirits
Industrial methylated spirits, or dry normal methds with oven-dried tapioca

Mix fresh, some days to dissolve completely, filter if any sediment
Apply finish to guitar, bridge, truss rod cover and pickguard (if there is one)
Seal first - use thinner cut, cloth or brush,

don't use a rubber that has seen oil when sealing

NB: immediately after sealing, check for inadequately sanded scratches, and fix them!

Traditional grain filling

Pumice after sealing, separate rubber, alcohol only

Then sand back with 240

Alternative: prep grain filling

filler before starting French polishing, sand back
Timbermate Natural Wood Filler, diluted with water to make slurry
Feast Watson Sanding Sealer

Build up sessions
Level micro bumps with 1200 + oil

be very careful not do break through finish layer - it is very soft when being worked
declog sandpaper with clean cloth

Optional: cut to matt with 1500, avoiding edges

For a deep, gloss finish, this can be done twice

Pay attention to edges around soundboard:

• since that was done in an earlier session, there might be some unevenness

• can be sanded down with 1200 + oil

Difficult area: neck to upper-side join

• use pointed pad to get into corner

• at some point, might need to tape off one face,
  to allow working on the other by itself.

Spiriting off

• separate rubber

• alcohol only, very lightly charged

• no oil - the point is to remove the oil

• also remove swirl lines (and put in much, much finer ones)

• should bring up gloss

• need to apply some pressure

• multiple sessions to avoid it starting to grab

Final steps?

Finest car polish??? With ultra-fine cutting compound.

• Must wait a week, so that polish is completely dry & hard

Wax / liquid furniture polish???

• make sure it is dry so it doesn't pick up fibres

Be very careful of the face that rests on the towel

Remove masking from fretboard and finesse fretboard-shallac transition

• use 350 grit sandpaper to "bevel" the portion of shellac that is on the fretboard

• be careful not to touch the actual neck

• apply lemon oil to the fretboard when done

• if the shallac and/or neck join transition is still troublesome to feel...

• ... try 1200 sandpaper + oil, minimising the amount of neck touched,

• ... a little bit of auto polish afterwards if required

Attach bridge

• But first, sand shellac from inside edges of saddle slot, so that saddle blank fits in firmly but not too tightly

• Don't do this until shellac finish on bridge is hard.
  Masking tape will lift incompletely-cured shellac, and the clamping bolts will deform it.

• Use appropriate drill bit to clean up bridge pin holes after finishing

• Remove masking tape if not done so already

* If we followed the "mask 1mm inside the true bridge outline" option

very carefully chisel away the "ridge" of shellac around the perimeter

Glue in bridge using bolts through the outer two holes, and one of the middles one, to clamp

• If the holes are accurate, actual bridge pins can be used to get position right (but clean them if any glue gets on them)

• Use 3/16" countersunk bolts and wingnuts if holes are correctly placed (7.5mm for bass)

• Otherwise use thinner ones so bridge can be positioned correctly

• You can use more bolts if required, but wingnuts require plenty of space around them,
  hence the "two outer and one middle" suggestion

• If the scalloping of the bridge underside is not adequate to clamp the bridge wings,
  use the C-clamps to do that.

After glue is dry, remaining hole(s) can be drilled if not done so already

• Need to wait until clamping bolts are removed so a piece of scrap can be held underneath

Ream bridge pin holes to size

• shoulder rings underneath heads should nestle into the countersunk rim

• After getting one right, use masking tape around reamer

Attach tuners and fit Straplok

Tuners - duh

• But... run a drill bit through the holes first, shellac will have made them too tight

Staplock tail hole: also duh

Staplock neck hole

Use strap button support glued in after fitting back to sides
Drill hole in body (masking tape)
27mm up from neck, centred
Bolt in place

Setup

Cut nut to rough shape

• Mark which side of nut is "inward facing"

• Start with the nut profile about 2.25mm above the fretboard (we'll be cutting it down later)

• Rough in with belt sander, then smooth using neck radius block

• Now is a good time to angle the top of the nut so that it is about halfway to the headstock angle. This will make it easier to cut slots that provide a clean break angle for the strings, and avoid "sitar buzz"

• For a 6mm nut, a fall of 1mm represents 9.5 degrees, which is pretty good (headstock is 14)

• Leave sides a bit proud so they can be blended into neck and truss rod cover (if it reaches the sides)

• Mark neck edges and centreline (eventual one will be different)

• Mark low-E position 0.5*nut-string-spacing up from centre, then the rest using the tables below

• (Alternatively, use a string-spacing steel ruler)

• Cut slots about 0.5mm deep (we'll be deepening those later too)

• Slots should slope/curve down towards the tuners

6-string (equal centers)

6-string (hybrid-proportional - recommended)

12-string

Bass (equal centres)

Bass (hybrid-proportional - recommended)

Bass nut edge clearance (space between outside of nut and edge of strings)

E string half-diameter = 1.4mm
G string half-diameter = 0.7mm
Worked example using 42mm nut width and the above spacings and half-diameter approximations

Start work on saddle

Mark which side of saddle is "inward facing"
cut slight radius curve on top of saddle

• Take about 2mm off the bass end, 4mm off the treble, leave the middle alone

• if using neck readius block, use it for smoothing only

Place in saddle slot, use straightedge to extend fretboard ends to saddle

• mark the, and use those marks to find string centre

Mark string positions on saddle

(summary table below, or more complete versions in "Making Bridge" section)

Cut very shallow notches - perfectly horizontal

String up guitar

Don't bring it up to pitch - nut and bridge are too high

Get action at nut sorted

For each string

• Press between second and third fret

• Check clearance at first fret - want "almost touching"

• Slightly higher for bass strings

• Using shadow of string from desk lamp is useful

• Cut slots deeper until the file binds,

• Then remove and sand off the top, leaving "semicircle" channels

Use this method to get first-fret action right

• Position a desk lamp behind and above the neck, at about eye level

• Look for the shadows of the strings,

• More specifically, look for the sliver of light between each string and its shadow

• Deepen the slots until those slivers of light are tiny and uniform

• A combination of parallax, neck radius and different string diamater will mean that the actual gaps will be higher for the bass strings, with an even graduation to lower for the treble strings