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Old 02-14-2017, 07:03 PM
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Bruce Sexauer Bruce Sexauer is offline
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Join Date: Jan 2009
Location: Petaluma, CA, USA
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Quote:
Originally Posted by murrmac123 View Post
Bruce, I would just like to clarify, if you would be so kind, as to why the tapers are different...

I am in the process of starting my first (well under the radar) build, and this tapered back strip melding into the end graft is a feature which I had figured into it , thinking I was being innovative, but I see I am 15 years away from being innovative...

The way I am constructing the back strip/end graft mating is to glue up the tapered strip initially overlength, ie the length of the back plus the height of the end bout, then glue up the two back halves with the center strip in between, which I assume is how you do it as well, and cut off the surplus to form the end graft. The angle will then remain the same ...obviously it requires precise measurement and cutting to get the widths at the "mating points" spot- on, and the width of the binding plays a part as well.

But as far as I can see the angle of the taper should remain the same , no ?
I favor the Martin proportioned graft. Were it continued it wold only go a few more inches before it vanished, and I need 20" more. So, to have the taper be the continuous, I'd either have to make the graft very wide or the taper very shallow. I use 2 tapers that cause their purflings to meet in the binding somewhere.

I inlay my back strip into a joined back. Otherwise, if they were were part of the glue-up, the back strip would have to be machined with 2 absolutely straight non-parallel edges, and I have no easy idea how to do that. Instead, I inlay the back strip imperfectly, and then inlay the purflings in individual channels which I can machine very accurately.
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