Drilling an End Pin Hole - Luthier Tips du Jour Mailbag
In this episode, luthier and instructor Robbie O’Brien answers a viewer’s question about how to drill a hold for an end pin jack during a pickup installation.
Video Transcription
[on-screen text reads: Luthier Tips du Jour Mailbag]
Mailbag question: Can you show me how to drill a hole in the end block?
Robert O'Brien: Today's tips du jour mailbag question comes to us from Minnesota. "Dear Robert, I have seen your videos on pickup installation, but they already had holes in the end block. I need to install a pickup in my guitar, and it's a first-time install, so therefore I need to drill a hole in the end block. Can you show me how this is done? Thanks for your videos, Doug in Minnesota."
Doug, I have a guitar on my bench right now waiting for a first-time install of a pickup. Now tell me what are the chances of that? It's amazing. Your email comes in, I've got a guitar ready to show you how to do it. I'm going to be installing the LR Bagg's Lyric Acoustic Guitar Microphone system in this guitar, and therefore I need to drill a hole in the end block. So come on. Let me show you how it's done.
Measuring and prep
Doug, I'm going to start by putting a piece of masking tape over the area where I want to drill the hole. The reason why I'm placing tape here is so that I minimize damage to the finish. Next, I'm going to come in with my ruler and find the halfway point between the thickness of the sides. This one's coming in at 115 millimeters, so half of that is 57-and-a-half, and I'm going to go ahead and just place a mark 57-and-a-half, right there. Now I can just eyeball the center line of the actual end wedge. Trust your eye, and X marks the spot. Now I'm going to get out my spring-loaded punch, place it right on the X that I just made, and give it a little pop.
That definitely marks the spot, and it increases the pucker factor slightly. Next, come in with your calipers and the actual pickup piece that's going to go into the end block, and measure it to see what the diameter is. Most of these come in at about a half inch. This one's coming in at about .047", so close enough to a half inch. So a half inch hole is what we're looking for. To drill the hole, you could probably come in with just a half-inch brad point bit and drill your hole. However, what I like to do is start a pilot hole. I'm going to start with a quarter inch brad point bit, and then I'm going to use this special step-up bit to step it all the way up to a half inch, and it tapers it and reams it out nice and smooth without damaging your finish.
Drilling and reaming the hole
Now, because I have a punch hole there, it's very easy to place the tip of the brad point in it and drill. Now I come in with the taper bit and go ahead and ream it on out up to a full half inch. And the rest of the installation from this point, Doug, is pretty straightforward. You now have a nice clean half-inch hole in your end block that didn't damage your finish. Now you can go ahead and complete the install. So Doug, thank you very much for your question, and I hope you have found this information useful.
[on-screen text reads: More Luthier Tips and online courses available at www.obrienguitars.com. Private and small group guitar building and finishing instruction available.]
