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JJohansen
09-06-2018, 07:21 AM
Hello everyone,

I'm working my way through binding a few new builds and have had idea id like to run by the more experienced builders.

Binding / purfling scheme is curly koa framed by a 1mm bwb purfling on both the side and soundboard / back faces.

I've glued the side purfling to the bindings and have bent them as one unit. They are bent to the exact shape using nifty technique that I'll share later.

I'm now thinking that if I glue the soundboard / back face purfling to the pre bent bindings, I would have one single unit to glue in place, rather than two. This would eliminate the problem I've faced of getting glue inbetween all mating faces. I could see this simplifying the process.

Am I missing anything here?

sequoia
09-06-2018, 09:48 AM
I've glued the side purfling to the bindings and have bent them as one unit. They are bent to the exact shape using nifty technique that I'll share later.

I'm now thinking that if I glue the soundboard / back face purfling to the pre bent bindings, I would have one single unit to glue in place, rather than two. This would eliminate the problem I've faced of getting glue in between all mating faces. I could see this simplifying the process.

Am I missing anything here?

Bending the binding with the side purfling attached is definitely the way to go and the only way I ever mastered. I use the aluminum foil method... In answer to your question about attaching the top purfling to the pre-bent bindings I have to say, why? The problem with the side purfling is that you are bending against the grain and thus the problems with puckering, etc. Wood doesn't want to bend that way. However, the top purfling is bending with the grain and thus there are none of the above problems. It should just lay in your purfling channel. Anyway, if I understand your question correctly, yeah, that could probably work, but would just be an extra step that is probably not necessary and who wants extra steps? You also might consider using the teflon strips during glue-up if you are worried about the purfling channel.

Allen
09-06-2018, 10:09 AM
There is nothing to be gained in doing this in one step. I'd highly recommend that you do this in 2 stages.

Glue your purflings to the back and sound board first. Then do the bindings / purfling combo.

If you are working with hardwoods for both back and soundboard, then it's OK to tape in place and wick in CA glue to tack them in place. Or use PVA or HHG. It will only take about 1/2 hour for them to hold in place and you can then go on with the rest of the job.

Beau Hannam Ukuleles
09-07-2018, 03:49 AM
If the bindings I happen to buy have purfling attached, great. Otherwise i just add them on the fly- with ukes i heat bend the waist areas of the purflings.