Drilling The Tremolo Claw Screw Pilot Holes

I drilled the pilot holes for the tremolo claw today.

The pilot holes are really difficult to drill because of the location. The Stratocaster back cavity is about 123 mm long, but the hole needs to be drilled in the shallow vertical wall of the cavity, so there's a shallow angle in the pilot holes.

The back of the body looks like this...

...So I had to get this:

It's a 12 inch extension for 1/4 inch hex shank drill bits. The bit is 7/64 inch. Originally I wanted to use an aircraft bit (extra long bit) but I couldn't find one in 7/64 at the local hardware store. However, I did some trigonometry by measuring the dimensions of the hardware, the body cavity, and the drill bit extension, and found out the angle would be shallow enough. What I found also surprised me, but I'll explain the interesting engineering properties of the body design in a later post.

The claw sitting inside the cavity.

Anyway, I marked up the locations of the holes and attempted to drill through the masking tape without starting the bit deep enough. You can watch the painful result of the first attempt for the first hole:

Yeah...the bit wandered. I ended up realizing pretty late that something was wrong. You can probably tell things are going to be a disaster seeing the bit bend like that...

Here's the second hole that ended up a lot better (since I started the bit by hand a lot deeper and then took the tape off):

I went back and drilled the right-hand side hole by using the claw as a jig to steady the location of the bit. It was extremely hard trying to start a good hole by hand once I had the bad drill path.

In the end, everything turned out all right, as the claw was able to fit within the position of the screws that would go into the holes.

The holes aren't as parallel as I like, but they'll be good enough to hold the claw.

I'm going to put a countersink on these holes before I use a screw to thread them, so it'll end up being better than this, fortunately.

I learned my lesson today: be careful with thin bits, and start a deep hole by hand if not using brad-point bits. Luckily, this is just the tremolo claw screw holes. This would have been bad if the bit wandered while I was drilling the body for the tremolo mount.

I'm still waiting on my screw wax, but I've got a few things left to do:

• Tap screw threads into the neck.
• Complete sanding of the neck pocket in the body.
• Remove the clear finish off the frets from the fretboard.
• Establish some measurements and mount the neck.
• Mount the tremolo.
• Order some pickups, solder them along with the electronics into the pickguard.
• Drill screw holes for the pickguard, assemble.
• Setup, then off to making music!