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Hi everyone,

I am cutting my binding channels by hand, using a Sloan type purfling cutter and a chisel. I can score deeply around the sides (5.5mm) , but how do I know that I am chiseling an even depth into the side ? Is it something that is done by eye, or am I missing something ? Thanks in advance.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Do you simply stick the blade out of the purfling cutter no more than than the depth of the intended binding ? I had trouble doing this as the hold down screw would hit the bevel and the blade did not want to stay in position. I placed the spare blade it came with over the bevel now and I can crank down the hold down screw and have my blade protruding to the depth of my binding. I think this is the answer. So never mind, unless you plan to share your hand cut binding channel tips, which I would be happy to hear.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

On my first, since my sides were about 2 mm, and my bindings were about 2 mm, I just chiseled down to the linings as a guide. It was actually pretty easy. I did, however, from a tip, use a scraping type of blade instead of a cutting blade on my cutter. The scraping blade tends to stay in line on varying grain, while a knife type tends to want to follow the grain. Alex uses a Graml, and I now have one of those, but I have not used it yet. I made my own cutter guide.

Now, the purfling channels were a bit more difficult. There you just need to eyeball a consistent depth. Seems to work fine. Eyeballing is pretty accurate.

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Waddy

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Sound Clips of most of my guitars

Ideally you want to make your bindings the same (or greater) thickness as your sides. Trying to pare away the sides whilst leaving a slither of the sides remaining is no fun, at least that's the case using the hand tool method.

Based on that I can increase me depth a little till I hit the linings - I was trying to maintain a little bit of side left, but i guess I really don't need to.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

My bindings are always 2mm or more, the sides never over 2mm.

When I work I alternate the scoring of the side with cutting from the face down, in other words I treat the binding same as the purfling. I switch from side to face cutting and eventually the two scored lines will meet. I always find myself dreaming for a second gramil and I never have the $ for it. Readjusting it every few minutes is a bit annoying.

Normally I start by doing a solid scored line around the sides. I don't need it full depth, just big enough to be easily seen. The I start chiseling the rosewood away. A sharp chisel, often re-honed, is really important. I stop when i see the lining. Often larger sections of rosewood can be popped-forced off the lining but for this you need nice grain and a good score-cut. Once most of the rosewood is off I score again, this time it is little left and easy to reach the lining. Now i can readjust the gramil to round and 2mm or whatever depth and cut from the face down. Either clean the rosewood and glue residue from the lining, or eventually go a bit deeper in. At this point you don't really need the chisel as the gramil cuts easily down through the soft lining. Eventually you can readjust and score the side again etc. The very last op is to chisel the edge of the side square, as it is often a bit over 90 thanks to the top or back doming. If you don't refine this part you might end up with gaps. Alternatively you can sand a a bevel in the binding or side purfling but I prefer to chisel the side.


Do more guitars like this and it gets easy

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Build log

I thought about doing exactly what you say Alexander, but I did not want to take the chance that I screw up adjusting the depth on my cutter and end up cutting slightly off each time... not sure that is likely to happen, but I wanted to avoid the possibility.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Regarding adjusting, I find the LMI gramil to be wonderful. It can be tightened to ridiculously safe levels. For setting the depth I use various feeler gauges between the blade and body. The blade is 1.5mm sharp, which is to be added or subtracted depending on how the bevel is facing. Press the blade on the gauge(s) tight, tighten the screw with the other hand and Bob's your uncle

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Build log

been there and done that

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Walter Lay
"It's taken me so long, but now that I know
I can see. All that I do or say, is all I ever will be"
- Billy Joe Shaver

The cut to the side can be made with an ordinary woodworkers cutting gauge. Cheap if you get the Beech variety. In fact it's probably easier to use than the Gamil.

I use the gramil tool from LMI. I use the tool to cut the binding (and purfling) channel into the top and then I use the same tool to cut the ledge into the sides. Of course when cutting into the sides, you have the gramil tool sliding accross the top or back, and you have to contend with the radius. I just make a simple wood wedge that matches the radius of either the top or the back and I tape it onto the surface of the gramil tool using double sided tape. Then the cutter of the gramil tool will be squared up to the sides and it will cut a straight binding ledge. I will usually have to quickly clean up the insides of the binding ledge with a chisel, just to get any leftover wood out of there. I hope that makes sense.

Thanks,

Jonas

ok for my second question -

I cut my binding channels using the Sloan cutter I have. It worked well. But of course, being cut by hand, there is some unevenness at the bottom of the channel, so how do you take care of this ? Just a mill file and run it around the channel to even out the bottom of the channel so the binding stays in there good and tight ? I am planning on trimming the inside corner of my binding so it sits in the channel better as well. So how do you get a tight fit ? File the channel square ?


I still have to attach my purfling and cut the purf channels, so I am getting a little ahead of my self. The binding was planed flat before I bent it - I need to rebend it as well. I suspect all that will help.

I want to stick to the hand cutting method even though it took me a week of off and on work to get to this point of cutting the top and bottom channels. But if my results are less than satisfactory - I will have to build a router guide for a down cut straight bit. So far my router experience on this guitar has been good, but the binding and routing channels, I dread.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

You can use a mill file with one edge ground flat so that you don't dig into the side while flattening the bottom. you can also use a small chisel held at a scraper angle to scrape the ledge. I used a combo of these techniques when doing my bindings by hand. Just try to get a nice even, square ledge.

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Aaron Craig

I have found an excellent tool for scraping binding channels. What I'm using is a lathe tool blank. You can get different sizes, but the one I've been using is a 1/4" one. It's about 2 1/2" long and has a slight bevel ground on the end. The bevel is perfect for fine scraping.

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Waddy

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Sound Clips of most of my guitars

I got some replacement spokeshave blades for the same purpose. Easy in the hand and wide enough so that I can see if Im off square.