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Chris_H
03-27-2013, 04:26 PM
I am at the stage of gluing bindings/ purfling on a body. Ledges are cut, and everything fits well. I have watched videos on youtube, and read various things... it is now time to do it. I am doing a side BWB purfling, a wood binding, and BWB/ zipflex /BWB on the top. I have seen this glued by taping the pieces all on with binding tape. and tacking things in place with CA glue, then removing the tape, and giving it a more thorough gluing. I have also seen it done with wood glue, working around the top, and taping after set into the glue. CA looks simpler, faster. I am concerned with CA leaking into the interior of the body, which I do not want!

The ledges cut through the sides into the kerfing, so there is a path for CA to flow in. I used the AST A4 kerfing, cut down to uke scale, the 'holding' wood seems just right, and its design is excellent, I like it. 1 set + 1 extra stick does 2 tenors.

Is it a bad idea to try CA glue, if being cautious? Thin? Medium?

Should I be using wood glue? Wood glue seems stronger in the long run.

Would love some guidance on this..

Thank you all...

gspears
03-27-2013, 05:02 PM
Chris. I too am at the same stage you are on my current build. I watched the youtube videos today by Obrien guitars. LOL! I also purchased and used the AST A4 kerfing and cut them down. The work really well and look and smell so good. I used the spanish cypress. I am using wood binding and a BWB purfling on the soundboard. I am anxious to see what others recommend. CA will dry really fast. I think maybe too fast for me, fiddling with the wood bindings, trying to keep them snug while taping and gluing, taping and gluing, etc..I'll be looking forward to the recommendations.

Rick Turner
03-27-2013, 05:38 PM
Shellac seal your binding/purfling ledges if you're going to use CA, and then yeah, go for it. Spray some accelerator onto the bindings and purflings and let it dry a bit first. You barely need to tape if you just work your way around. You'll undoubtedly glue yourself to the uke several times, but what the heck...

Chris_H
03-27-2013, 06:39 PM
I just learned something kinda cool about sealing ledges and channels with shellac. I misplaced the brush I had been using, a liner, so I chose a 'sword striper', a pinstriping brush. This one is made by Grumbacher, but others undoubtedly make decent ones too. It is made for laying out pinstripes, clean, thin, accurate lines. Other brushes do not even come close to the length of fine line a pinstriper will lay out, and clean too. This works slick for the ledges. It cost about $15, so this is not a disposable brush. Not really a big deal, but if you take care of the brush, it sure is pleasant to do a really clean, fast job of putting shellac on ledges. The difference is about 10 light dips in the shellac, ( could probably do less if you focused on it) instead of (possibly) lots more. This was leftover from my painting days, hasn't been used in ages.


Thank you Rick.

Gonna glue this stuff on in the morning after I sleep on it. I think CA is in the mix somewhere.

Something else I observed... I am using BWB purfling that is narrower than the thickness of the binding by about 0.015", and it is all separate, not BWB joined to binding. The deepest part of the ledge cut, is the depth of the purfling to enable miters at the heel graft, and is stepped out from the main ledge for the binding. ( sorry if that is confusing) It looks like the binding could be glued on with wood glue (cleanly) and then the side purfling slipped into the resulting slot, with whatever glue ( the slot has a nice fit) and then the BWB/ zipflex/ BWB could be done after. Not sure I will do it this way, but I think it would work. I kind of like the idea of wood glue at this point, for joining to the sides, the BWB, and the binding. I feel that it has a little better impact resistance for the longevity of the instrument. Still, CA looks like it is an industry staple, if not standard, for gluing bindings.

Cheers!

Michael Smith
03-27-2013, 07:45 PM
I tape the binding and purfling on then wrap the uke with 1/8th inch shock cord that I bought on ebay in a 100' roll. I pull the tape as I'm wrapping the shock cord. You can really pull the bindings in with shock cord nicely. CA doesn't stick to the shock cord all that well.

Chris_H
03-28-2013, 10:03 AM
Success.. I used a small tack of CA to secure the side purfling mitre, wood glue to glue the bindings and most of the side purfling, then CA to fill the top purfling, and to seep in to the side purfling, making sure there are no voids. Oh, yeah.. and a wee bit of HHG for the joint where the curly Maple binding meets the tail graft. Maple can show glue lines more easily with any imperfections, and HHG seems to give slightly more invisible joints than other glues. The most difficult part was letting go of my anxiety. It was more difficult in my mind than in real life.

Very pleased..

Rick Turner
03-28-2013, 12:10 PM
I used to do the long bungee cord thing, too. That was with thick celluloid binding and Duco cement. What a mess!

ksquine
03-29-2013, 07:38 AM
CA will be fine if you can control it well. Get some of those tiny applicators or syringes. Straight from the bottle can lead to big drips

thistle3585
03-29-2013, 03:47 PM
I'm a big fan of Duco for gluing binding. I especially like it on bound fretboards because it doesn't wick in to the slots like CA.

Chris_H
03-29-2013, 05:32 PM
I was very pleased with wood glue.