Guitar Build Process

Quick links:

Access port cover and frame
Neck block & tongue assembly
Truss rod
Neck, headstock & heel
Headstock veneer
Continuing the neck
Sides
Finishing sides
Back and soundboard
Fitting back and soundboard to sides
Bindings
Fretboard
Fitting neck to body
Making bridge
French polishing soundboard
Complete all construction steps
French polish rest of guitar
Attach bridge
Setup
Hardware information
Build history

Before beginning build

Access port cover and frame

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

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

While at it:

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

Model

Bent lengths (2.5mm)

Straight lengths (2.5mm)

Bass

98mm, 106mm, 25mm

100mm, 125mm, 50mm

GP

66mm, 73mm, 25mm

100mm, 125mm, 50mm

Parlour

66mm, 73mm, 25mm

100mm, 125mm, 50mm

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

Milled stock

Applying heat

Bending in mould

Drying bent pieces

Covers

Model

Inner layer

Outer layers

Bass

100x98mm

125x106mm

GP

100x65mm

125x73mm

Parlour

100x65mm

125x73mm

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

The border process is

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

Laminating cover layers

Cover pieces

Frames

Dimensions:

Cut all pieces, using laminated cover for measurements

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

Notes

For tops and bottoms:

For side pieces:

In every single case:

Acess port layers

Clamping

Assemble each layer using cover as template,

Frame components

Laminating frame veneers

Joining frame pieces step 1

Joining frame pieces step 2

Drill holes in cover and frame

Dremel drill press
1/8" bolts - will use brass nuts and bolts
Drill first in corners of port cover as guide, from outside inwards

use a sharp drill bit
3mm holes, centres about 6mm in from edges
back with 19mm scrap on drill platform, raise hanging edge (from workbench) with 27mm scrap 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

Frame pieces trimmed

Drilling cover

Drilling frame

All access port components

Neck block & tongue assembly

Resaw and mill 19 x 65mm tas oak stock into 7.5-8mm 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)

Bass:

135++mm

(neck end dimension 125, but there is an upward ramp)

GP:

105++mm

(neck end dimension 95, ditto)

Parlour:

100++mm

(neck end dimension 90, ditto)

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

Component

Bass

GP

Parlour

Base

65x20

65x20

65x20

Thin upright

115x19

85x19

80x19

Thick upright

115x28

85x28

80x28

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

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)

Component

Bass

GP

Parlour

Tongue

110x45

80x45

75x45

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)

Laminating receiver back plate

Laminating neck tongue

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

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

Option #2

Drill 5mm deep 10mm diam counter-holes in the exit (neck)

Force-fit nuts into 10mm holes, so they are flush
Clamp tongue to avoid splitting
Thread a bolt 15mm onto the nut
Use the bolt as a centering guide to hammer the nut into the 10mm hole
Check that the bolt can engage with the nut from the other (body) side

To facilitate fitting the neck, there is one more step

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

 

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)

Scale length

Body fret

Aluminium Channel

Threaded rod

24"

12

277

285

24"

13

294

302

24"

14

310

318

24.5"

12

284

292

24.5"

13

301

309

24.5"

14

318

326

24.75"

12

287

295

24.75"

13

304

312

24.75"

14

321

329

25"

12

290

298

25"

13

308

316

25"

14

325

333

25.5"

12

296

304

25.5"

13

314

322

25.5"

14

332

340

34"

12

404

412

34"

13

428

436

34"

14

451

459

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 and end nuts should fit snug into the aluminium channel
weld the nut to the rod
cut socket bolt, leaving about 7-8mm of free coupler thread
fit socket bolt to coupler
cut notch into coupler, up against socket bolt head
weld the two together, in the notch
grind the weld pretty
grind off the coupler facets manually, then put holding 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

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

Truss rod components

Truss rod preparation

Truss rod welds

Truss rod progress

Truss rod ready for assembly

Finished truss rod (not yet sealed with masking tape)

Neck, headstock & heel

Cutting necks

Headstock scarf angle ~14deg = 19 rise over 75 run, slope = 0.248, angle = 14.2, hypotenuse = 77.4

Headstock section

Stock width

65mm is good for 6-strings and basses, consider something wider for 12-strings,
(so that "non-slip" screws, below, won't risk interfering with neck/headstock transition

Some worked examples (see Final Table, below)

Fingerboard section

25.5"/14th

359 - 6 = 353

24.5"/14th

345 - 6 = 339

24"/12th

305 - 6 = 299

34"/14th

477 - 6 = 471

Headstock section

6-String

170 + 30 + 10 = 210

12-String

210 + 30 + 10 = 250

Bass

170 + 30 + 10 = 210

Initial "notional" length before scarf cut

25.5"/14th/6-String

353 + 210 = 563

24.5"/14th/6-String

339 + 210 = 549

24"/12th/12-String

299 + 250 = 549

34"/14th/Bass

471 + 210 = 681

Pad out by 10mm each end, cut, then mark scarf cut position

Model

Cut stock length

Scarf cut start (from body end)

25.5"/14th/6-String

563 + 20 = 583

353 + 10 = 363

24.5"/14th/6-String

549 + 20 = 569

339 + 10 = 349

24"/12th/12-String

509 + 20 = 529

299 + 10 = 309

34"/14th/Bass

681 + 20 = 701

471 + 10 = 481

Cut stock lengths

Bass 701, scarf cut start 481mm from body end
GP: 583, scarf cut start 363mm from body end
Parlour 12*12: 569, scarf cut start 309mm from body end

Final table

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

Scale length

Body fret

Stock length

(12-string)

Scarf cut start

24"

12

529

569

309

24"

13

546

586

326

24"

14

562

602

342

24.5"

12

535

575

315

24.5"

13

553

593

333

24.5"

14

569

609

349

24.75"

12

538

578

318

24.75"

13

556

596

336

24.75"

14

573

613

353

25"

12

542

582

322

25"

13

559

599

339

25"

14

576

616

356

25.5"

12

548

588

328

25.5"

13

566

606

346

25.5"

14

583

623

363

34"

12

656

436

34"

13

680

460

34"

14

703

483

Heel pieces

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

Bass:

125 at neck

6 pieces (7*19=133)

GP:

95 at neck

5 pieces (6*19=114*)

Parlour:

90 at neck

4 pieces (5*19=95)

(For the GP, 5 pieces will probably be too much, but 4 is sometimes too little)
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, and make sure each wedge-edge is straight and square

Scarf joint jig

After cutting scarf joint

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)

Consider next time

Align scarf joint using scarf joint clamping jig

This will prevent two problems

Glue up & clamp

Cleaning scarf joint faces

Gluing scarf joint (old method)

Scarf joint clamping jig

Gluing scarf joint with jig

Heel pieces cut

Gluing heel pieces

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.

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

Scarf joint/volute diagram

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!
Mill a length of 10*12mm timber to fill in the neck-join area past the truss rod end
(don't glue in place yet)

Headstock wings

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

6-String,Bass

185mm

12-String

220mm

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)

Gluing reinforcing spline

Gluing headstock wings

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
- 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

Setting up to thin down headstock

Neck pieces, front

Headstock veneer

Resaw & mill Blackwood and Huon / Celery Top / Radiata 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 lamination tends to render the piece curved, so I no longer do this)
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.

Setting up pantograph

Routing headstock logo

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

Logo channel filled with glitter

Logo channel filled with resin

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.

Logo sanded level

Headstock veneer marked up

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.

Headstock preparation

Headstock veneer slot and bevel

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

Gluing headstock veneer

Neck with headstock veneer attached

 

Continuing the neck

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.

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

Deepened channel at body end

Deepened channel at nut end

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)

Truss rod sealed with masking tape

Gluing the truss rod

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

25.5"/14th-fret

359

24.75"/14th-fret

348.6

24.5"/14th-fret

345.1

24"/12th-fret

305

34"/14th-fret(bass)

477

No we can plan neck width profile

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

6-string:

56 at 14th fret

12-string:

59 at 12th fret

Bass:

58 at 14th fret

Mark *centred* nut neck width

6-string:

44

12-string:

48

Bass:

42

Rule in neck edge cut-lines

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

Take already-glued-together heel block stacks

Bottom of stack will be ~45mm
Bottom of heel will be 35mm
Glue & clamp, with about 5mm spare each end

Marked up neck

Gluing the heel stack to neck

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.

Heel curve cut and sanded

Neck outlines drawn ready for cutting

Use this diagram to rough-in heel curve.

Roughing in heel curve

This is a very rough guide

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

use a strip of ply of mdf underneath the neck-length, hold the neck against the mitre.
Clean up the lines on the belt sander (but be careful not to dome it)

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

Neck and headstock rough cut, bottom

Neck and headstock rough cut, top

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

Neck facets

"flare" facets outward around volute and inward 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

First facet lines

First facets cut

Second set of facet lines

Seconde set of facet cuts

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.

Neck shaped and smoothed: heel end

Neck shaped and smoothed: headstock end

Fingerboard

Mill Merbau/Jarrah to 6.5mm, 66mm wide

Rough cut lengths

25.5" scale

510

24.5" scale

490

24" scale

480

34" scale (bass)

650

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

Fingerboard bevels cut using slanted cradle jig

Fingerboard profile using radiused 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.
So far, we've been using plain old pine for the inner layer, that is perfectly adequate, however some customers might well prefer something more top-shelf.

Milling sides stock

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

Bass

155 x 950

GP

120 x 850

Parlour

113 x 800++

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

Resawn side stock

Side stock milled to 2mm

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

The mould used to bend the sides

A Fox-style side steam bender

Pre-heating sides

Steam bending non-cutaway sides

Steam bending cutaway sides

Bent sides after allowing to dry

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

Bindings ripped and milled

Bindings bent using same process as sides

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!)

Gluing the sides for lamination, see laminating moulds to the rear

Laminating non-cutaway sides

Laminating cutaway sides

Sides laminated

Fitting sides to solera mould

Model

Neck width

6-string

56

12-string

59

Bass

58

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

Sides trimmed and fitted in the solera

An assortment of solera turnbuckle clamps

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

Profiling sides: flat for the top, curved for the back

Curved sanding sticks used in side profiling

Trim bottom of sides to create curved back profile

Invert, mark dimensions for cuved back

Position

Bass

GP

Parlour

Tail

max- 6

5

4

25%

max- 2

2

2

50%

max 0

0

0

75%

max- 9

7

6

Neck

max- 25

20

18

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

Position

Bass

GP

Parlour

Tail

144

110

104

25%

148

113

106

50%

150

115

108

75%

141

108

102

Neck

125

95

90

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

Back profile from neck end

Back profile from tail end

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

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)

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

Neck block cut and contoured

Gluing the neck block in place

Gluing access port

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

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

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
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

Trimming access port

Channel for tail strip

Gluing tail strip

Routing access port hole

Access port hole routed

Access port hole squared out

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

Gluing inner layer of access port

Door removed after using it to align the glue-up

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

Fix curvature of cover (wet / heat gun, clamping)
Or use a tighter curve when laminating in the first place

Also, consider

Previous approach (not recommended, not shown in images)

Finish access port

Prepare the following

To create the outermost lamination

This almost final perimeter fit

Before proceeding, check that inner cover curve matches guitar

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

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

Remove nails

Index pins (nails) to align outer layer of access port

Fitting the access port outer layer

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)

Gluing the access port outer layer

Preparing to glue the nut strips

Gluing the nut strips

Finished access port

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

Kerfed lining stock milled

Bandsaw jig for cutting kerfs

Kerfed linings cut

Bevelling the kerfed lining for the cutaway horn

Gluing kerfed lining

Sides levelled ready for soundboard and back

Resawing, milling, butt-joining back and soundboard

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

Model

Length

Width

Board width

Bass

570

460

230

GP

500

410

205

Parlour

470

390

195

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

Resawn boards for soundboard and back

Soundboard and back boards drum thicknessed

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

Jointing the soundboard to prepare for butt-join

Preparing to butt-joining the soundboard

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

Butt-joining the soundboard

Tracing the body shape to soundboard

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

Mill to required thickness using drum sander

* Soundboard

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

Clearly mark centre lines

Body shape traced onto soundboard and back

Soundboard and back outline roughly cut

 

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)

Bass

110

95

110

110

leaving 130 to tail

GP

99

86

99

99

leaving 117 to tail

Parlour

93

80

93

93

leaving 110 to tail

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

8x5mm, long enough for eight x body height

Bracing timber milled

Bevelling bracing pass one

Bevelling bracing pass two

All bracing pieces sectioned

Prepare A-frame soundboard braces size and positions

Two pieces, 8*19 (vertical taper)

from neck joint to a spread at tail of

Bass

165

GP

149

Parlour

140

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

Bass 165

GP 150

Parlour 140

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

Bracing preparing to profile

Profile rough-sanded into one of the braces

Fine-sanding the profile to one of the braces

Profiling finished on one of the braces

Fine-sanding profile to one of the A-frame braces

All braces profiled

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)

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

Gluing back braces

Gluing (middle three) centre strips

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

Tapering back braces

Fitting soundboard braces

Gluing soundboard braces

Tapering soundboard braces

Preparing soundboard bridge plate

Body-fret to full-scale line

24.0 12-fret

304.8

24.5 14-fret

277.2

24.75 14-fret

280.0

25.5 14-fret

288.5

Bass 14-fret

384.7

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"

Bass:

120mm

12-fret 24.0":

120mm

14-fret 25.5":

85mm

14-fret 24.75":

83mm

14-fret 24.5":

82mm

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

Fitting bridge plate, soundhole support and neck support

Gluing bridge plate, soundhole support, neck support and wing braces

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

Cutting channels in sides for back braces

Gluing outer two centre strips

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)

Cutting channels in sides for soundboard braces

Gluing vertical braces

Cut and fit support backing for pickup socket

Cut and fit support backing for neck strap button

Socket and strap-button supports cut

Gluing socket and strap-button supports

Socket support

Strap button support

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.

Starting to glue the back, note rudder to align neck-block

Clamping the back using Go-bar deck

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

Trim overhang carefully with flush-bearing router

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

Gluing the soundboard to the body

Body fully enclosed for the first time

Trace, cut and smooth soundhole

Trace outline using template as a guide

Positioning

(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
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!

Soundhole cut and sanded

Cutting channel for cutaway-neck join strip

Before routing the binding channels

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 is square!
NB: also, makeabsolutely sure the guitar body is straight and secured in the cradle, so the channels are perfectly vertical!

Direction of cuts

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

Router jig for cutting binding channels

Cutting binding channels

Rough-cut neck-tongue pocket

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

Binding channels cut

Gluing the vertical neck-body boundary strip

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

Bindings tilt

There are currently two choices for bindings

For accent layers, current recommendations

Soundboard side

Rounded back

Important: to reduce tilting of bindings due to curved back

Fine-tuning tilt-bevels

Clamping method

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.

The bindings elastic clamping jig

A simple stand for holding the bindings while preparing to glue them

The guitar body is held in one half of the solera mould

Clamping the bindings with elastic

Sand and scrape away a small wedge at these areas for curved back

Clamping bindings to the back

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:

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

Bindings corner with notch filed

Bindings corner with wood filler (later, after attaching heelcap)

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)

All bindings attached

Binding shaved, scraped and standed level

 

Making a fret-position template for the StewMac jig

Jig for large calipers to make fret slotting template

Scribing lines at fret positions

Cutting slots for the fret-slotting jig's index pin to fit into

Completed fret-slotting template

Plan fretboard fret count and width

Width extension ratios (of positions of fret pairs)

19th/14th

1.2

19th/12th

1.33

21st/14th

1.27

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

width at nut:

44

width at 14th fret:

56

(nut+11)

width at 21st fret:

58.4

(nut+14, which is 14_delta * 21st/14th ratio)

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

width at nut:

48

width at 12th fret:

59

(nut+11)

width at 19th fret:

61.2

(nut+13.2, which is 12_delta * 19th/12th ratio)

Bass / 14 body fret: 19 frets

width at nut:

42

width at 14th fret:

58

(nut+16)

width at 19th fret:

63.3

(nut+21.3, which is 14_delta * 19th/14th ratio)

Slotting fingerboards for frets

Use jig & template

Setting up the height of the saw guide

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)

Cutting fret slots

All fret slots cut

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

Fretboard mounted "askew" on backing MDF board for trimming.
The cut-line is parallel to the (closer) MDF edge

Cutting one side of the fretboard to width

Cutting the other side (after re-positioning with double-sided tape)

Fretboard trimmed, sanded to final width, and with wave-motif cut

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 tangs 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

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

Holes drilled for fretboard inlay marker dots

Fretboard dots flooded with CA glue

Fretboard dots sanded level

Holes for fretboard side dots (without jig)

Fretboard side dots inserted

Side dots flooded with CA glue

Fretboard side dots sanded level

Jig for drilling side dots

 

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

6-String:

Gotoh SG381-01C

12-string:

Wilkinson 3+3, SKU TU-141-010

Bass:

Gotoh GB-707C

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)

Hole diameter

6-string

10mm

Bass

14mm

Fretboard index pins in neck

Tuner holes drilled in headstock

Estimate neck angle

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

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

Slot for neck tongue cut in neck

Fitting the neck, checking multiple alignments

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

Heel cap rough cut, note bevelled edge

Shave 'n' shim on neck tongue to correct roll

Glue neck to body

Determine correct length and trim furniture bolts for clamping

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

Gluing the neck tongue into the neck

Gluing the neck to the body

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

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

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

Levelling neck-soundboard transition

Levelling neck-cutaway transition

Making bridge

Mark full-scale line on soundboard

24"

609.6mm

24.5"

622.3mm

24.75"

628.6mm

25"

635.0mm

25.5"

647.7mm

34"

863.6mm

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

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

Planning bridge height

Bridge blank

Cutting saddle slot

Slotted bridge blank

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

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

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

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:

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

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

Laminated bridge components and clamping caul

Laminated bridge blank

Plan string spacing (Saddle)

6-string

0

11

22

33

44

55

Bass

0

19.3

38.6

58

12-string

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

String

Offset

Delta

E1

0

E2

3.2

3.2

A1

11.4

8.2

A2

14.6

3.2

D1

22.8

8.2

D2

26.0

3.2

G1

34.2

8.2

G2

37.4

3.2

B1

45.6

8.2

B2

48.8

3.2

E3

57.0

8.2

E4

60.2

3.2

Hole diameters

Type

Bridge

Body

Regular pins

5mm

4.5mm

Thin-tapered pins

5mm

4mm

Allparts Bass

8mm or 5/16"

5/16"

Drilling bridge pin holes using a template

Bridge pin holes if not using a template

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

Filling saddle slot ends

Contouring bridge wings

Contouring bridge top

Finished bridge

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

Plan bridge placement

Find and mark lateral placement first

Use StewMac Saddlematic for lengthwise placement

Preferred option

Option shown in image

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

6-string

12-string

Positioning bridge laterally

Positioning bridge lengthwise

Drill bridge pin holes in body

Setting up to drill bridge pin holes

Two middle holes drilled and secured

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

If using grain-filling

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

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.

cut straight lines and easy curves around bridge with sharp cutter

Consider variation from previous builds

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

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

Starting to French polish soundboard

Bridge and fretboard masking tape removed

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

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

Pickguard

Truss rod covers showing cavity in rear for protruding nut

 

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,

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

The temporary heel clamping wedge

Gluing on the fretboard

Attend to any minor sanding of the fretboard-neck join

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

Attaching the heelcap

Heelcap carving finished

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

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

Grain-filling

Installing frets

My fretwire choices

Instrument

Part #

Name

Inches

mm

Guitar

152

Oversize Medium

.092 x .048

2.34 x 1.22

Bass

149

Jumbo

.103 x .046

2.63 x 1.16

Important

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

Yes

After cutting fretwire into lengths

Fret slots are too tight

StuMac recommends against widening them,

promoting a tang-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

Cardboard protection for the soundboard

Bending the fretwire

Tools using for installing frets

First few frets installed

Adjustable support strut for upper frets

All frets installed

Snip off fret ends

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

File 35 degree bevel using 35 degree jig

Check that the fret tops are perfectly level

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

Fret ends snipped off

Fret end file guides

Fret end dressing file

Fret ends dressed and polished

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:

Difficult area: neck to upper-side join

Spiriting off

Final steps?

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

Wax / liquid furniture polish???

Be very careful of the face that rests on the towel

 

Blocks to hold small pieces while French polishing

French polishing progress

Remove masking from fretboard and finesse fretboard-shallac transition

Attach bridge

* 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

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

Ream bridge pin holes to size

Drilling bridge holes

Gluing the bridge

Bridge attached

Reaming bridge pin holes

Attach tuners and fit Straplok

Tuners - duh
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

Strap buttons fitted

Tuners installed

Cut nut to rough shape

6-string (equal centers)

String

Offset

E1

0

A

7.2

D

14.4

G

21.6

B

28.8

E2

36

6-string (hybrid-proportional - recommended)

String

Offset

E1

0

A

7.4

D

14.7

G

21.9

B

29

E2

36

12-string

String

Offset

E1

0

E2

2.3

A1

7.7

A2

10

D1

15.4

D2

17.7

G1

23.1

G2

25.4

B1

30.8

B2

33.1

E3

38.5

E4

40.8

Bass (equal centres)

String

Offset

E1

0

A

10.75

D

21.5

G

32.25

Bass (hybrid-proportional - recommended)

String

Offset

E1

0

A

11

D

21.6

G

32

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

Segment

Value

Cumulative

E edge clearance:

3.95

3.95

E half diameter:

1.4

5.35

E-A spacing:

11

16.35

A-D spacing:

10.6

26.95

D-G spacing:

10.4

37.35

G half diameter:

0.7

38.05

G edge clearance:

3.95

42

Starting work on the nut

Progress cutting the nut (better exposure next time...)

Start work on saddle

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

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

Mark string positions on saddle

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

Cut very shallow notches - perfectly horizontal

Bass:

0

19.3

38.6

58

6-string:

0

11

22

33

44

55

12-string:

0

3.2

11.4

14.6

22.8

26

34.2

37. 4

45.6

48.8

57

60.2

Starting work on the saddle

Progress cutting the saddle (better exposure next time...)

String up guitar

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

Get action at nut sorted

For each string

Use this method to get first-fret action right

First fret action

Setting nut action using "shadow" method

The finished nut

Check neck relief

Tune guitar to D (two semitones down)
Measure relief using straight edge (use fret-slotting templates if ruler too long)

Desired relief

  • 0.25 to 0.3mm (more for bass is probably OK)

Adjust truss rod if necessary

Get action at 12th fret sorted

Stu Mac recommendations (guitar)

Bass E

Treble E

(mm)

(mm)

1st fret |.023" |.013" |0.58mm|0.33mm|
12th fret|.090" |.070" |2.28mm|1.78mm|
(These seem awfully low for an acoustic)

Some TalkBass forum numbers (bass)

12th fret|3..6mm|

Good initial target (guitar)

String

Height (mm)

E1

2.8

A

2.65

D

2.5

G

2.35

B

2.2

E2

2.0

Good initial target (bass)

First fret (pressing 2..3): 0.55mm?

String

12th fret(mm)

E

4?

A

3.6?

D

3.3?

G

3?

My first fretless: about 3.5mm all strings

G string lower at nut for "mwah", all others higher for clear tone

My first fretted: about 4.0mm all strings

Check action at 12th fret for each string using action gauge

Use Excel spreadsheet to track, update and recomment how much to remove

Slacken string, remove bridge pin, file notch deeper
Replace bridge pin, tune up, check action
Slacken all strings, remove saddle, sand to a smooth curve connecting shallow notches

Replace saddle, check intonation

If problems, use a small triangular file to cut slanting V-notches to move string pivot forwards or backwards
If any saddle-buzz, dome the contact points (or two 1/3-way V-notches)

Finish and fit nut semi-permanently

Position nut so strings are correctly centred
Mark edges with sharp pencil
Grind / sand / file so the transitions to the neck are flush and smooth
Fix nut with two drops of CA glue (each side of the truss rod nut)

Attach pick guard and truss rod cover

pick guard: double-sided tape (two narrow strips, top and bottom)
truss rod cover: screws

Finished saddle

Preparing to attach pickguard and truss rod cover

Attaching the picguard

Finished pickguard

Truss rod cover attached

The finished access port

The final guitar, front

A view of the back

My choice for tuners

Bass:

Gotoh GB-707C

6-string:

Gotoh SG381-01C

12-string:

Wilkinson 3+3, SKU TU-141-010

My choice for frets

Bass:

149

Jumbo

.103 x .046

2.63 x 1.16

FW-001-149

Guitar:

152

Oversize Medium

.092 x .048

2.34 x 1.22

FW-001-152

Build #1 - fretless bass

  • most of 2020

  • over-braced (25++mm A-braces, solid wing braces, too-thick bridge plate)

  • 4mm soundboard, 4mm back(?)

  • Plays and sounds great

Lessons learnt

  • double-check before drilling lead jack hole

  • always turn away from work when pouring alcohol onto French polishing rubber

  • French polish soundboard before attaching bridge

Build #2 - 12-string 12-body-fret 24" scale Parlour

  • 2021-22

  • over-braced (25mm A-braces, solid wing braces, thinner bridge plate

  • 3.5mm soundboard, 4mm back

Lessons learnt

  • Don't pipeline multiple guitar builds this early, lest learning the same lesson three times

  • Go thinner on those soundboards

  • Go more aggressive shaping necks

  • Think carefully about bridge placement (scale length / body fret choices)

Build #3 - 25.5" scale GP

  • 2021-22

  • slightly over-braced (22mm A-braces, solid wing braces, thinner bridge plate)

  • 3.5mm soundboard, 4mm back

Lessons learnt

  • Don't pipeline multiple guitar builds this early, lest learning the same lesson three times

  • Find a way to French polish soundboard before attaching freboard

Build #4 - fretted bass

  • 2022

  • bracing about right...

  • 3.2mm? soundboard, 4mm back

Lessons learnt

  • Don't pipeline multiple guitar builds this early, lest learning the same lesson three times

  • Be more careful about neck angle, and if not, level frets before setup

  • Protect soundboard before installing (and snipping, and filing) rets

Build #5 - 24.5" 14-fret Parlour

  • 2022

  • Neck milled to 17mm

  • 3.0mm soundboard, 3.5mm back

  • much less over-braced

  • No grain filler on soundboard, experimented with Feast Watson sanding sealer on rest of guitar

  • Slightly asymmetric bridge due to carelessness drilling pin holes

Lessons learnt

  • Drill bridge pin holes to achieve repeatable bridge placement before French polishing soundboard

  • Consider masking bridge and fretboard position 1mm inside actual line to hide transition boundary

  • Change bridge height calculation (2mm lower?) - excessive grinding down of saddle profile has been a repeated issue

Build #6 - 25.5" 14-fret GP

  • 2022-23

  • Neck milled to a whisker over 16mm

  • Access port cover with border to improve appearance

Lessons learnt

  • if taking sides out of lamination mould early, put them back again after breaking squeeze-out joins

  • cut cutaway sides longer than marked, trim back as necessary

  • get serious about verticality of sides before gluing neck block

  • ...

 

 

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