Scary Neck Repairs: A Roscoe

[Bruce Johnson]

Another Scary Neck Repair! Steve sent us a Roscoe 6-string bass with.....you guessed it...a stripped out truss rod. Jeremy and I have never done surgery on a Roscoe before, but we're up to the challenge. We don't turn away fine basses suffering from neck problems.

A handsome looking bass. Red-orange/black sunburst on the body and a plain maple fingerboard. The neck is fine overall, no real bow or twist or anything bad. But the truss rod nut is stripped out, so the truss rod can't be adjusted. Steve decided that he'd like to get it fixed right, so it can be accurately dialed in. So, he sent it to us for the surgery, to replace the truss rod.

Jeremy (aka Dr Freekmagnet) and I will both be working on this job, doing different parts of it. He got started by disassembling the bass, and putting the body back in the case.

We'll be routing off the fingerboard, pulling out the truss rod, and making up and installing a new truss rod. Then a new maple fingerboard, and new frets.

Roscoes have these cool oval inlays. Part of the signature of their design. Steve asked if it was possible to save these inlays, and reinstall them in the new fingerboard. I said that I couldn't guarantee it, but I'll give it a try.

Note how the Roscoe fingerboard is heavily rounded at the edges. And the fret ends are blended in. Nice details. This is a high quality, well made bass.

Okay, Dr Freekmagnet has finished his first part. The hardware is removed, the frets are pulled out, and the neck is set up in our main neck fixture. Ready for me to try to extract the inlays.

A better look at the inlays. They are synthetic pearl, quite thin. I believe the black arches were cut by a CNC router, and then filled with some kind of black resin.

Here's the basic technique for extracting the inlays. The neck is set up in the fixture, with the fingerboard surface leveled just below the height of the rails. I set up a router with a flat base and a 1/4" bit, to slide on the rails. I'm going to steer the router freehand, sliding it around.

I set the router depth to cut about 1/16" deep, and freehand a "P" shape around the oval. Close to it, but being very careful not to touch the inlay.

Then I use a narrow 1/8" chisel to peel away the maple around the outside of the oval....Gently.....

Then I put the edge of the chisel under the edge of the inly and very gently pry it up....It popped up, no real problem. They're glued in with CA glue.

With the first one successfully removed, I went ahead and routed around all the rest of them.....

And used the same technique with the chisel to trim the maple around the outside, then pry them up.

And there they are....Three of them broke while prying them up, but that's not really a problem. I saved the pieces, and I'll CA glue them back together as I install them in the new fingerboard.

Next up: Continuing routing off the fingerboard, and pulling out the truss rod! Some mild violence involved! No, not really.

 

[Bruce Johnson]

Jeremy took over:

Back at the neck fixture, he routed off the rest of the fingerboard, right down to the glue line.

The fingerboard is gone, turned into a pile of maple sawdust. This Roscoe has a single truss rod down the center and two carbon fiber bars. It's a stiff neck, even though it's fairly thin.

Cleaning out the area around the end of the truss rod with a favorite Luthier tool: a narrow screwdriver.

Wedging the screwdriver under the end of the truss rod, and giving it a few light hammer taps......

Okay, here's the violent part. You may not want to watch. The Roscoe's truss rod was embedded in some kind of silicone sealing compound. Dr Freekmagnet had to use the surgical vise grips to peel it up out of there. His expression reflects the thrill of the moment as it broke free......

And there it is. It got bent a bit during the extraction process. This is a Single-Acting Double-Rod truss rod design. Not very common these days. It's all steel, welded at the far end. It's painted or coated with something copper colored. The nut threads onto the bottom rod. The nut is soft steel and thin walled. Easy to strip out the hex. The threads and the rod were okay. But, by its design, it would have been very difficult to remove the nut and replace it.

I'm going to put in a better, stronger truss rod. Probably a Single-Acting Single-Rod design, embedded in epoxy. That's up next.

 

[shwashwa]

My bass! I'd also like to point out that the truss rod needed to be adjusted because it was too much relief but it was maxed out, which is how it became stripped... Was under the impression that it was a dual acting truss rod so didn't try a shim. Either way, looking forward to getting this thing playing well!

 

[walterw]

roscoe is in NC so i see a lot of them, great basses with one of the best low Bs in the business

Was under the impression that it was a dual acting truss rod so didn't try a shim

that's a non-sequitur, neck heel shims have nothing to do with what the truss rod does; you can't compensate for one by changing or adjusting the other

 

[Bruce Johnson]

This project is sitting for a couple of days right now, because of me......I had a nasty flare-up of tendonitis in my right foot, and I'm hobbling around on crutches right now. That obviously slows me down, working in my shop.

If it's not better in a few days, I'll have Jeremy do the truss rod installation. With me sitting nearby, supervising.

Speaking of truss rods: Right now, I'm planning on installing one of my standard Single-Acting Single Rod Embedded truss rods. That will fit into the Roscoe neck with minimal modifications. And it will be much stronger than the original.

But...I could put in a Double-Acting Single Rod Embedded truss rod. There's enough space in the heel to fit the DA head assembly in there. It's a little more machining and routing work, but not difficult. About an extra $25 to the bill for the extra labor.

I don't think you need a Double-Acting truss rod in this neck. It's unlikely it's ever going to go into a back bow and need to be pulled forward. But I'll offer it if you like some extra peace of mind.

 

[Bruce Johnson]

roscoe is in NC so i see a lot of them, great basses with one of the best low Bs in the business

that's a non-sequitur, neck heel shims have nothing to do with what the truss rod does; you can't compensate for one by changing or adjusting the other

Hey Walter;

I think Steve was referring to putting a shim washer under the nut of the truss rod. It might have been possible to back the truss rod nut out, and replace it with a stronger one, and a shim washer. But it would have been tricky getting that nut out of there. It's a weird design, flared out at the back end. Like it's made so it can't be removed. I don't know why they did that.

 

[walterw]

I think Steve was referring to putting a shim washer under the nut of the truss rod.

OK that makes more sense and yeah, not a thing with a typical 2-piece rod

 

[JuanB]

I love these threads, Bruce! Thank you!

 

[staccatogrowl]

On one hand, it saddens me to see someone other than Keith Roscoe working on a Roscoe bass. On the other hand, if someone other than Keith is working on a Roscoe, it's definitely in excellent hands with Bruce Johnson (good choice, @shwashwa ). Also, the Roscoe shop has many new build orders, and they often receive priority over repairs.

While those distinctive oval and crescent inlays were quite common on older Roscoe basses, they are no longer standard, or typically offered as an option. Nice work preserving them. Is it an older model, Bruce?

It can be disclosed without divulging a serial number, by commenting on neck construction. The oldest Roscoe models have scarf-joint necks, evolving to necks without volute. The current carved-top Custom and Signature Roscoe models have volutes. Which neck construction is the bass you're working on (scarf joint, no volute, or volute)?

Otherwise, I am "subscribed" to the thread. Best in your repair journey, as well as the bass traveling back to the lucky owner of a beautiful Roscoe 6 string! Cheers : )

 

[shwashwa]

roscoe is in NC so i see a lot of them, great basses with one of the best low Bs in the business

that's a non-sequitur, neck heel shims have nothing to do with what the truss rod does; you can't compensate for one by changing or adjusting the other

I was talking about taking the truss nut off and shimming the truss rod with washers

 

[shwashwa]

Roscoe would have had the opportunity to work on it if they had returned any of my calls.... I believe this model is from 94 with a scarf joint

 

[walterw]

I was talking about taking the truss nut off and shimming the truss rod with washers

gotcha

i just never hear those spacer washers called "shims" though i suppose that's what they are

either way this is super interesting!

 

[Axtman]

 

[Bruce Johnson]

View attachment 5495333

Yep, these repairs are scary. Most bass owners and many Luthiers are frightened by the idea of heavy surgery on their prized bass necks. So, I started using the title Scary Neck Repairs for this series of threads. You can search using that and read them all. A whole list of expensive basses having their necks cut open!

I bought the domain name Scaryneckrepairs.com, in case Jeremy and I ever want to build this up into a sideline business.

 

[Bruce Johnson]

Finally, the Roscoe neck rebuild is moving forward again, toward completion! I'm sorry for the delay; it was my fault. I had a medical problem and was unable to walk at all for a month. It was miserable attempting to work in the shop on crutches. But I'm mostly healed now, and back to working part days.

Where we last left off, the Roscoe neck was waiting for me to make up a new truss rod for it and install it.

Here is the new truss rod, ready to be installed....

It's a Single Acting Single Rod Embedded type truss rod, a standard design that I used on all of my basses for about 10 years. Simple, very strong, and has a much better mechanical ratio than the original Roscoe truss rod. And it fit into the Roscoe neck with very little modification.

Here it is, fully installed in the neck. It's cast in place in a bed of hard epoxy.

I covered the design and installation of this truss rod in more detail over on this thread:

https://www.talkbass.com/threads/building-your-own-custom-truss-rods.1640596/post-28604798

Okay, jumping forward. Once I had the truss rod installed, Jeremy milled and prepared a nice piece of plain maple for the new fingerboard. And here it is being glued on......

It's glued on with West Systems epoxy, face down on one of my neck gluing beams. Masking tape and wax to keep the epoxy squeeze-out off of the pretty external surfaces.

Unclamped, peeling off the tape. We leave the fingerboard oversize when gluing it on.

....Yeah, a bit oversize.......He trimmed it down to about 1/8" overhanging on the sides......

The next stop is the Neck Radiusing Fixture, to bring the fingerboard down to thickness and radius. Nice and straight on the neck.

Then over to the Fret Slotting Saw......

To cut all the slots.......

And here it is, back over on my bench! The new fingerboard is radiused and slotted, still with 1/8" overhang on the edges.

Next up is my job, to put the inlays back in. That's going to be done by hand routing, with some patience. Jeremy requested that I do it. Okay. That's on my list for the next few days.

When I'm done, it'll go back to Jeremy to finish up. He'll trim and sand the fingerboard, put in the side dots and spray a few light coats of polyurethane on it. Just the fingerboard. Then put in the frets. Level, crown, polish, as usual.

 

[Jeff Scott]

Glad to read you are on the mend, Bruce!

 

[Bruce Johnson]

Good grief, it's November! And we're finally wrapping up the rebuild of this Roscoe. The delay was on me, reinstalling the original Roscoe inlays into the new fingerboard. I took a more complicated approach to the job, using my Pin Router, as an experiment. I wanted to work out the tooling and technique for doing precision inlay routs with a Pin Router. I didn't charge the owner, Steve, for the extra R & D time. It came out very well. I showed that process over on my Pin Routers thread:

https://www.talkbass.com/threads/pin-routers-the-old-school-production-workhorses.1405214/page-24#post-28750369

So, the inlay re-installation in the new fingerboard is done:

They look almost exactly like they did in the original fingerboard.

Next up: putting in the side dots. I used 1/8" black ABS rod stock, set in #30 holes with CA glue.

The dots haven't been trimmed yet in this picture, which is why they look fuzzy. After they were in, I filed them down flush and rounded off the edges of the fingerboard to match how they were on the original. Then I trimmed and radiused the heel end, cleaned up around the truss rod nut, and final sanded the fingerboard surface to 400 grit.

Three coats of Stew-Mac Fingerboard Oil gives the maple about the same tint and semi-gloss shine as the original.

That's the end of my part of this job. Now Jeremy will put in the new frets, get them all leveled and polished, and get this Roscoe back together.

 

[fhm555]

Have you ever tried debonder on something like those inlays?

 

[Bruce Johnson]

Have you ever tried debonder on something like those inlays?

No I haven't. I don't think it would have helped much in this case. These inlays were really thin, a few were barely 0.015" thick. And very brittle. Applying Debonder and trying to pry the inlay up from the recess probably would have shattered them. That's why I used the method of routing away the wood all around them, and then carefully inserting a chisel under them from the side. I only had four breaks, and they were clean breaks of larger pieces. I was able to CA glue them back together.

If they had been thicker, like 0.050", then Debonder might have loosened them enough that they could have been pried up.

 

[Dirk Diggler]

Hey Bruce,
thanks for documenting the repair so well, as always.

I do have to ask, why not just remove the whole fingerboard in 1 piece?
Seems like so much work to remove all the inlays and all of that effort.

It's very possible using a clothing iron and some careful use of a thick putty knife.
I've done it successfully several times over the years.

That said the end product is awesome, great job.
After all, that is what matters. I'm sure the customer will be thrilled.
Dirk

p.s. I will never understand why people have such a challenge adjusting and then stripping out truss rods.