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Okay I have read alot since my fisrt binding question including most if not all the threads here Cumpiano's book and another acoutic guitar building book but I still have a question on what the "optimal" goal in cutting the channel besides being uniform, smooth and level.

Obviously the purpose is to protect the seams along the top and back plates while adding a decorative flair.

When cutting the channel do you generally just take off a narrow strip of the top and back plates just exposing a level portion of the top and back of the sides?

Or do you cut out an semi equal amount from say 1/2 or 1/3 of the outer side thickness as well?

In theory either way you are gluing up two sides of a four faced strip of binding and the plates and sides each get one glued side.

On the other hand despite being institutionally and certifiably analytical I somehow consistently understimate the complexities involved in any given task.

I think that makes me a very frustrated overly optomistic cynic but I will have to think about that one for a while.....

I cut my purfling rabbit in the top first. I cut it .05 - .06 deep and the full width in one shot. I also scribe this line witha gramil which helps to achive a really clean cut. otherwise expect some fuzzing.
Then I cut my binding channel which is shy of my side thickness by just a hair. My bindings are typically .08 thick and I thickness my sides to about .085. I cut these full depth in one pass also.
I also scrape a small chamfer on the inside of my bindings, this helps them set flush in the rabbits.
Not sure if that answered your question or not, but maybe.

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Jim Watts
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Jim,

Interesting tip on chamfering the inside of the binding to help it sit flush....thanks alot for that.

Cheers

Interesting tip on chamfering the inside of the binding to help it sit flush....thanks alot for that.

That kind of helps create a word picture but I am planning on just a single strip of rosewood around the top and back.

I wonder if I should just go for one straight groove or a rabbit in two passes with the appropriate chamfer on the rosewood?

What would be less problematic for a beginner?

[quote=Scooter B]I still have a question on what the "optimal" goal in cutting the channel besides being uniform, smooth and level.[/quote]

I think the "optimal" goal in cutting the channel is to make it match as closly as possible the binding which is to fit inside the channel.

Yes the binding is there to protect the seams, but also to add a "hard" edge for those clummsy friends we all seem to have. Also, like a book, it "binds" all the pieces together so it doesn't look ugly, now, if you are using similar material for back and sides, sometimes it works out alright (say mahogany back and sides) to "hide" the seam, it's there though and a binding is a good idea.

I think the Stew Mac site has a good picture of the binding ledge, actually so does the Cumpiano book.

Here is a doctored up picture



As far as the chamfer goes, it is on the inside edge of the binding strip, it never gets seen. It's there so that the inside edge does not interfer with seating the binding, this will help get a tighter fit.

The next question is, what are you using to cut the groove/rabbit (same thing here)?

You always want this "groove" to be straight, parallel with the sides, not registering off the top or back as usually these are domed to some radius.

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