Fitting a new bolt-on neck - Part 3

So, this bolt-on neck we’ve discussed over the last couple of weeks gave us a bit of a run for our money. We saw a method of fitting it to the body and how to plug and re-drill the mounting screw-holes. That’s all done and we should be on the home stretch. Just need to mount the tuners and string it up.

Gah! Seems this neck has one last trick up its sleeve. The tuners that my customer bought for this project don’t quite fit. The tuner holes in the headstock are too large for the tuner bushings. Actually, the holes are stepped—the front is wider than the rear and there’s still finish at the back—so it’s possible that someone was over-enthusiastic with a reamer-type tool when clearing finish.

Larger bushings can sometimes save you in situations like this but they aren’t an option in this instance and so we need to do some hole-work.

Now, ages ago, I talked about some strategies for these sorts of situation. The obvious answer is to plug the holes and re-drill them. However… I don’t have a round piece of maple this size and don’t want to blow the cobwebs off the lathe to turn one. Much more important than that, though, sometimes the plugging-and-drilling option isn’t the best way to go.

Let me try to explain. After plugging a hole with a new piece of wood, you need to take some care re-drilling the new (smaller) hole. If the new hole size is quite close to that of the old hole, it’s possible for the very thin slivers at the sides of the plug material to tear off the walls of the original hole. This is less of an issue with smaller holes and guitar tuner sizes are a little more forgiving (you still need to take care, of course). As the hole sizes creep larger, this risk creeps up too.

So, in this case, with a relatively large hole to plug and with a re-drill size of pretty close to the original, I decided to leave the cobwebs on the lathe. Another contributing factor in this decision was he fact that our holes are tapered (wider at the front) and I felt widening them to accept a non-tapered plug wasn’t the best idea.

So where do we go from here?

We add a layer of wood around the walls of the holes. Essentially, we glue in a circular shim.

Where the heck do we get a circular shim? We make one.

We start with some maple veneer. In this case, edge-banding strips will do quite nicely for our needs (remember our doll’s house floorboards?).

I’ve cut some strips a little higher than the depth of hole to be filled and a little longer than the circumference of that hole. Being edge-banding, these still have a layer of glue on one side. Don’t worry, we’ll take care of that in a minute.

First we need some hot water. I boiled the kettle, filled a small bowl and popped my maple strips into the water. After a minute, I took them out and scraped the glue from each—it comes off quite easily. Then, I refreshed the bowl with more hot water and popped the strips back in.

A note here. I’m using very hot water—essentially just a bit below boiling point. It cools relatively quickly in this open bowl but I do have to add a caution to be take care. If you’re considering trying this don’t scald yourself. Be really careful.

After another minute or two, I took a strip from the water and tried bending it. I used a round piece of wood, close to the hole size, as a ‘former’ and began to bend the strip around. The veneer has a certain amount of flex anyway so this generally happens relatively easily. However, it can take a few tries. Don’t force anything. You’ll feel how the wood is bending and, if it doesn’t seem quite pliable enough, pop it back in some more hot water for another minute or two.

Eventually, I get to the point were I can ‘roll’ the strip all the way around the former. Then, I add a clamp to keep it there while it dries. I repeated the process for the other strips and left them until the next day.

When dry, the strips maintain most of their new shape. There’s an amount of spring-back but that’s fine here. Fit them to the holes and use a sharp scalpel to carefully cut them to length. Now, it’s a relatively simple job to glue them into the tuner holes.

As for clamping them in place while the glue cures, I made a wedgie device. Using the (almost-the-right-size) wood I'd used as the former, I cut off a section and then cut that lengthways on a diagonal. I ended up with two pieces that I could slide along each other to widen and wedge into the hole. This does leave a section to the left and right of the wedge where it doesn't contact the hole walls but these pieces were close enough to the hole size to begin with that it didn't really matter.

Bushings mounted, it’s an easy job to install the tuners. Oh, wait… Not it's not. As it turned out, the conveniently pre-drilled screw holes on the rear of the headstock didn’t match the new tuners either. More plugging and drilling. Why does this neck hate me so? Why? Why? To the last, I grapple with thee, thou damned bass neck!