Robbie O’Brien demonstrates how to drill tuner holes in your peghead.
Drilling three evenly spaced holes in a straight line can be a daunting task. This task is made much easier by using a tuner hole jig like this one available from LMI. I’ve been using this one to drill tuner holes in my classical guitar peghead for years. LMI also makes a version for drilling classical or steel string tuner holes and you can use the same jig to cut the slots.
Start by cutting out the perimeter of the peghead. You will notice that my peghead still has my template attached to it from cutting out the shape. Then mark the middle of the tuner slots. I have these lines conveniently marked on my peghead template. Square these lines down the side of the peghead on both sides.
As I do this, let’s talk a little bit about cutting out the perimeter of the peghead. If you’re using a router and a router table, be extremely careful. Especially going across the grain at the tip of the peghead. Remember, we want all ten fingers to be able to play our guitar when we’re done building it.
With the centerline on the tuner slots clearly marked on both sides of the peghead, I then clamp it to a flat surface, such as a workbench. You will notice that the jig that I’m using has three lines drawn on it. These lines are in the middle and directly over the tuner holes. When positioning the jig, I match up the centerline on the jig with the centerline I just squared down the side of my peghead. If I were to drill the tuner holes now, they would not be in the center of the side of my peghead. I measure the distance of the peghead above my jig and divide that by two. I then place a shim of that thickness under the jig. My shim usually comes out to be about 2mm thick, about the thickness of my classical guitar sides.
Now I can clamp the jig to the table. Notice how I am placing the C clamp in between the tuner holes. Make sure that the bushings are on the side of the jig that the drill bit enters. When clamping the jig to the table, just snug it up. It’s not necessary to crank down hard on the C clamps. Also, make sure that the centerline of the jig is lined up with the centerline on the peghead.
Next, mark the length of the rollers of the tuners. And mark this on the center of the back of the peghead. This lets us know how deep we need to drill. You can place your drill bit next to the peghead and jig, and use a piece of masking tape to mark how deep you need to drill. You are now ready to begin drilling the first tuner hole.
A 13/32 sized drill bit is usually the industry standard for tuners. It’s best to pull the bit out occasionally to allow the chips to be ejected. Keep drilling until the masking tape that you’ve placed on the drill bit encounters the side of the jig. Now go ahead and drill another hole. To keep the neck from being pushed away from the backside of the jig, place a hand on it and hold it while you drill.
After all three holes are drilled on one side of the neck, you can now release the clamps and check to make sure you drilled deep enough. You can do this by placing the tuners into the holes and make sure that they are seated completely. If the tuner doesn’t go all the way in, then drill the holes slightly deeper.
With the tuner installed completely, check the space above and below the tuner to be sure that it is, indeed, in the middle of the peghead. To drill the tuner holes on the other side of the peghead, leave the jig clamped to the table. Take the neck and spin it around, and then re-clamp it to the table in front of the jig. Make sure that your centerline is lined up and then drill the holes.
When clamping the neck to your table, I like using cam clamps like the ones shown here. You could also use just regular C clamps as well. The important thing is to make sure that your neck is securely clamped to the work surface so that it will not move when you insert the drill bit. Drill the holes on this side of the peghead the same way that you did the holes on the other side of the peghead. Remove the drill bit periodically to help eject the chips. Also, keep a firm hand on the backside of the peghead to guarantee that it won’t move away from the jig as the drill bit is drilling. When drilling the middle hole and the hole closest to the nut, you may notice that the drill bit goes all the way through and encounters the hole that you drilled from the other side. This is normal.
After all three holes are drilled, once again insert the tuners to make sure that you’ve gone deep enough. If necessary, drill the holes a tad deeper. With both tuners installed, you get an idea of what the finished peghead will look like. Now you can go ahead and cut out the tuner slots. Thanks to this slick little jig, a difficult task has become relatively simple.