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We've touched on this a bit in the past. I've got a Scheider gramil that I haven't used yet, and I'm just about to the point where I need to cut the binding and purfling channels, so I thought I'd see if I can gather a few more tips.

Do you typically just use the gramil to break the top fibers of the wood, and then just go from there with a sharp chisel?

I'm also a bit curious about what order to mark and cut for the stair-step ledge for purfling and binding. Do you mark the top for the whole width of the binding/purfling, and cut the channel just deep enough for the purfling... And then mark the width and depth of just the binding and then cut the rest of the binding channel to full depth. (I hope that makes sense).

In an archive thread, I really liked an idea for a tool that Mike Mahar showed using an exacto blade and using pieces of the binding and purfling to permanently set the depth. I'm going to try the gramil first, just because I already own it, but his design looked really simple and slick (and inexpensive).

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Jonathan Kendall, Siloam Springs AR

Here is Mike Mahar's version of the gramil if you're curious:

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Jonathan Kendall, Siloam Springs AR

I interviewed Jay Hargreaves for AL #83. He studied and worked with Richard Scheider for years, and he uses the gramil for his binding channels. I believe he has contact info on his web site (www.jthbass.com). He's a very friendly guy and would probably be happy to be contacted about his methods.

It's interesting to me to note that Jay uses power tools and jigs for all sorts of things, but he still does his binding rabbets this way. He must find it efficient, accurate, fun, or all of the above.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Here are a couple of shots of the gramil I came up with this evening.



I used Mike`s illustration for the basic principle, but after mounting the blade and trying it, I found the blade wandering off track and following grain runout (not good).
Therefore; I thought about cutters and decided to shape my blade just like a saw blade with a flat cut on the bottom and a raked angle toward the waste (not waist) side. A single toothed saw, if you will. Works very well! Took a little practice and technique, but I won`t be intimidated by the thought of a router getting out of control or set up wrong anymore.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

I only use a purfling cutter on portions of my bound headstocks and around where the end graft joins the purfling. I bought my purfling cutter from martin years ago, but the princples of using a cutter is the same. If
your blade wanders you are taking too deep of a first cut.
I think you need to set the depth of cut very shallow, just barely scoring the wood. Then set the blade slightly deeper with each successive cut. The first cut acts as a "guide" for the blade in successive cuts.

That`s what I was thinking at the time myself, Paul. I also thought the blade I was using was too thin and flexing. I forgot to mention that I ditched the thin blade and worked down an old utility knife blade. I just knew I kept those things in a jar for some silly reason!
Now that I`ve worked on technique instead of just making something work, I will probably try the origional single bevel knife cutter again. Actually, what I came up with tonight is a variation of a rabbeting plane.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

I wonder if it'd be helpful to make a right and left handed one, so that you'd be cutting "downhill" across the grain so the knife wouldn't want to wander into the grain.

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Jonathan Kendall, Siloam Springs AR

I use the Schneider one from LMI, and its a great tool. The blade works really well, with two bevels like an arrow pointing down. Not like a double bevel knife, one side of it is flat.

I don't take a light pass, and the blade never wanders. It is an ideal setup for scoring the lines before routing. I score just the outermost edges - the purfling - and come back with a router, and never get any tear out.

I've done it by hand with a chisel as well, on a few occasions. Its worth doing, to know you can do it the old way.

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Instagram: @jfrenchluthier
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