Arm Bevel Block Size - Luthier Tips du Jour Mailbag
In this episode, Robbie O’Brien answers a viewer’s question about the size of an arm bevel block.
Video Transcription
[on-screen text reads: Luthier Tips du Jour Mailbag]
Mailbag question: I'm considering doing an arm bevel on my next guitar. What size of block should I use?
Robert O'Brien: Today's Tips du Jour mailbag question comes to us from Montana. "Robert, I'm considering doing an arm bevel on my next guitar. My question is about the size of the block I should put in the guitar. Any advice is helpful. Mike in Montana."
Well, Mike, that's a very good question. The first thing I offer as advice is be careful. Anything you put on that guitar as far as inlay, arm bevels, sound ports, anything you do to dress it up, that's where the eye is going to go. So make sure that you can execute that step well. If not, it's going to look real bad. Now with that said, I have an arm bevel that's going on a guitar over on my bench right now. Let's go over there and I'll show you the size of the block I'm using on that guitar.
Block size
So Mike, here's the guitar in question and I've already installed the block. Let's first of all talk about the species of wood for the block. I use either basswood or Spanish cedar. I like the light weight also, they're very stable. Also, I tried something new on this particular guitar, I went ahead and profiled the side where the arm bevel binding is going to come in before I bent the side, and that seemed to work pretty good. Then, I shaped the block and put it in. The size of the block and the size of the bevel, here's what I've figured out, 3/4 inch down the block then is 1 inch. In other words, I've got a 1/4 inch glue line on the side, and I'm going to have a 3/4 inch bevel this way. Same thing coming this way. I've got 1 inch of block, 1/4 inch of that, the top's going to glue to, and then I've got 3/4 of an inch for a bevel.
Now by the time you shave that, obviously, you're going to have much more surface or much more real estate than 1 inch or 3/4 of an inch. You're going to have a little bit more of that area. I've found that that size bevel looks pretty good on a steel string guitar. On my classical guitars, I make it a little smaller. It's a little more streamlined to go with the classical guitar design.
The inside of the guitar, the block needs to be shaped somewhat. You want it to come in and hit your kerfing on both sides here. All of this is going to get knocked off here in just a few minutes, actually, with a file or a rasp and I'll come and shape the inside. So it's a little more streamlined on the inside. But those are the basic rough dimensions of my block. And I think if you follow that, you'll have a very decent size arm bevel on your guitar.
So Mike, thank you very much for your question and if you want to learn more about how to execute the arm bevel or the arm rest, Kent Everett from Everett Guitars, a good buddy of mine has a great DVD, an instructional DVD that walks you through every step of how to execute that arm bevel. And I think if you research that, you'll have a lot better chance of having a great looking arm bevel when you get done. So happy building.
[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.]
