A shocking experiment with epoxy!

[Sea Devil]

I'm making a replica of a 1966 Epiphone Crestwood Deluxe, using a circa 2010 Wilshire Pro as a donor guitar. I got my hands on some Z-Poxy and used that as a pore filler, then built up about seven layers of it on the back of the neck. I sanded it flat and added a few coats of JB Weld, building the neck up by about .20". I also enlarged the headstock by about an inch using epoxy putty. I'm only at the primer stage, but both experiments give every indication of being a success, although of course it takes a few passes to get uniform absorbtion of the finish, given the shared solvents between epoxy and lacquer. That does make for great bonding, though! Here's what it looks like so far.

The plan is to keep it as a two-pickup guitar at first and add the third pickup if I decide that my homage to the MC5's Fred "Sonic" Smith and Deniz Tek of Radio Birdman really has to be that accurate.

This is just the primer stage, btw. It will be finished in Mohawk Heritage White. The sloppy control cavity routing is original to the guitar. Pickup cavities will almost certainly get further adjustment (more epoxy). The headstock is slated to be routed for binding as well.

 

[Telenator]

Nice work.

 

[TF from MN]

Fascinating to see how you have built shapes up using epoxy putty. I wouldn't have thought it possible.

I read somewhere that jazz/studio guitarist Howard Roberts, frustrated with the small size of the neck of his guitar, used auto body putty (I presume Bondo or the equivalent) to increase its thickness.

 

[bebopbrain]

Great project and much more authentic than mine, which started with as a Warmoth telecaster body.

 

[old wrench]

Did you use JB Weld Kwik-Wood putty for the build-up?


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[Sea Devil]

I used Mohawk epoxy putty for the headstock enlargement and pickup cavities, and original formula JB Weld on the neck. It would have been very difficult to get an even layer of putty over such a large area.

I've used Kwik-wood before. It's better than the useless PC Woody, but I very much prefer the Mohawk -- easier to mix evenly and to shape, less plastic-y texture, sands better, and is less likely to have voids or bubbles. I used a couple different shades, which shows here. I have real USA Grover Rotomatics for authenticity's sake. Their size seems to be the main reason that the Crestwood Deluxe has an oversized headstock. They would make the guitar incurably neck heavy without the Bigsby; I may even need the third pickup just to keep it balanced!

Bebopbrain, how on earth did you deal with the neck/body relationship on yours? I think it looks great in spite of the differences from a Crestwood.

 

[Sea Devil]

After applying a light coat of white Mohawk primer-sealer over the Z-Poxy, it needed additional pore filling. The primer and the new epoxy mixed into a gooey white hybrid substance that spread and smoothed very easily and dried faster than the Z-Poxy alone. The epoxy underneath was not affected. I guess that qualifies as an experiment, too, although it was an unexpected one. I had heard of Z-Poxy being applied over vinyl sealer, but not white primer. I shot subsequent coats of the primer and vinyl sealer more or less together (wet-on-wet) after that for optimal hardness, smoothness, and coverage. I'm already at the no-sand stage everywhere but the front of the headstock as a result.

 

[bebopbrain]

Bebopbrain, how on earth did you deal with the neck/body relationship on yours?

It is a bolt on Warmoth neck that I bought used. The body is rock maple thicknessed to 1 3/16". I hoped the maple would hold the neck firmly despite the double cutaway. I reshaped the headstock (subtraction only) and had a luthier do the headstock binding for me. Very interesting what you do with addition!

 

[Sea Devil]

The real Crestwood bodies are 1 3/8". I think that extra sixteenth above your dimensions is what makes it (barely) possible to mount the jack on the pickguard.

I'm planning to do a real scratch build of the same guitar in trans black burst and have already made the body. When the Wilshire body popped up for next to nothing, I changed course. This build should be faster and cheaper.

I thought of just cutting off the headstock and attaching a new one made from one piece of wood, using a scarf joint better than the one already on the guitar. I even started to make one. I used a cardboard template to make it; the wooden headstock then served as a template for another template made of Garolite, which I used to shape the existing headstock. The original cardboard template has small guide holes for drilling the tuners. I stuck it to the headstock and used the thin red string that comes with a Bigbsby B5 kit, passing it it through the E string slots, the bridge, and into the Bigsby to double-check where the tuners need to be mounted for straight string-pull. The pic below is before the outline was fully refined, based on dozens of photos and ten sketches of paper, using ellipse and circle templates to match the curves on my reference photos. The end result us closer to the original shape than the lovely recreations of the great French luthier Roger Daguet!

 

[Telenator]

Bare in mind that the pickup cavities might sound best with the pole screws landing at the harmonic node of the strings. If you're going to be doing the work in that area, this would be a good time to straighten it out.
The bridge pickup is not as critical as the neck pickup. And often find that the sound benefits considerably by moving the bridge pickup towards the neck about 3/16" from its original position.

 

[Sea Devil]

Here are those two templates. The cardboard one is pretty rough, and is mostly for positioning the tuners (see above).

I was tentatively planning to use the Garolite one as an overlay, but that would make the headstock much too thick.

 

[Sea Devil]

Telenator, interesting point about pickup placement. I'm loath to remove any more wood at the neck joint, though. There's barely enough there as is. I'm already wondering if I'll need a full-on custom pickguard, given how poorly the stock guards typically fit around the pickups and the base of the neck, so slight changes in pickup placement would only serve to make that decision for me.

I'm not aware of any consideration of harmonic nodes (which only come into play on open strings and certain frets) coming from manufacturers other than Fender. Teles certainly put the neck pickup right there, so much so that there's no audible 5th fret harmonic on the neck pickup alone. The old DeArmond Rhythm Chief allowed for adjustable placement, of course, and could also me mounted right in that spot. I'd have to do some pretty exhaustive research to see how many other examples there might be.

 

[Boreas]

Heavy?

 

[Sea Devil]

With no Bigsby, tuners, or electronics installed, this is the lightest guitar I've ever held. It should balance well in the end; the current center of balance is exactly at the 21st fret.

 

[schmee]

I used Bondo repairing a caved in side on a hollow guitar once. I pulled/pushed the caved in side wood together and glued it there to hold it. It would not come up flush to the side surface though, had maybe an 1/8" max low spot. I used Bondo because it sands readily unlike thick hard epoxy, and fills better like putty. It actually turned out great after finishing the repair etc.

OP: Did you add to the neck because those are a thin flattish neck?

 

[Sea Devil]

I just did a balance test: with the Rotos in a bag taped to the headstock and a B5 taped in place on the body, the guitar is neck-heavy, but not egregiously so. The tuners weigh 9.5 ounces and the Bigsby 10.5, but the tuners are much farther away from what would otherwise be the balance point, so they have more effect. I hope the weight of the pickups will help even things out. I have a set of lightweight Sperzels if I decide to deviate from the original design, but I did just spend $50 on three bass-side Rotos to match half of the vintage 3X3 set I pulled of an old Gretsch I restored.

Schmee: yes, I absolutely the hated the "slim-taper" neck profile. It's now more like a Firebird, narrow at the nut but quite deep, with a flattish spot where it joins the headstock. I measure .92" at the first fret where it used to be .78". Night and day!

The fun part will be cutting the binding channels for the headstock. I'm handy with a router, but I don't know how it could reach the tight curves near the nut without a very fancy jig*. Also, the router would encounter different materials along its path (wood and epoxy) and might perform unpredictably as a result. I think I'll probably cut them using a neat tool called a Schneider gramil, which I already have. It's a marvel of simplicity and expressly designed for scribing and cutting into one face of a piece of material using the perpendicular face as a guide. Even with this tool, the last 5/8" or so of the curve will have to be done with knife and chisel.

They almost certainly did the headstock binding before installing the fretboard on the originals, and probably before carving the back of the neck with its fall-away curves where it transitions to the headstock.

Here's a pic. The curved side is used on inside curves, the straight side for outside curves and straight runs. You just reverse the chrome piece that holds the blade to switch between sides. Adjusts for blade depth and for distance from the body of the tool in both orientations, with the blade always at the same angle relative to the body.

Slow but accurate, perhaps up to 1/4" in depth, at which point the cut might need cleaning up and fudging. Depends on your touch, I suppose.

*Neither the base of the router nor the collet on the bit would be able to touch the needed reference points, so there has to be a jig. How to do it? Maybe just screw on a piece of masonite thick enough to allow for the router to get clearance, perfectly true the edges of the two attached pieces, and rout past the masonite to the appropriate depth. I still think the variety of materials would probably make the router jump, stutter, and bite too deeply at times. And the collet would have nothing to rest on in the areas where the neck curves away. But I digress...

 

[ventures_in_space]

They almost certainly did the headstock binding before installing the fretboard on the originals, and probably before carving the back of the neck with its fall-away curves where it transitions to the headstock.

The binding was actually attached to the headstock overlay prior to fitting, the whole thing was glued on as one piece. I have one here somewhere. Very nice work!

 

[Sea Devil]

I've since discovered that to be true, or at least that's the way Roger Daguet does his:

 

[Winky]

Bare in mind that the pickup cavities might sound best with the pole screws landing at the harmonic node of the strings. If you're going to be doing the work in that area, this would be a good time to straighten it out.
The bridge pickup is not as critical as the neck pickup. And often find that the sound benefits considerably by moving the bridge pickup towards the neck about 3/16" from its original position.

The node suggestion is interesting. The nodes of maximum (and minimum) amplitude will vary as the string is fretted in different places. This feels like it would be an issue with notes where the maximum or minimum nodes were right over the poles pieces would be disproportionately loud or soft. But it doesn't seem to be an issue at all. Certainly not one I notice, in any case.