BYO: glue for veneering

noodlenot

Could some of the knowledgeable folks help me out? i did some experiments with veneering (which is very new to me) and reached two conclusions:

- Brazilian rosewood veneers are terrible to work with (fragile, splintery, prone to wormholes)

- Gluing veneers with hot hide glue is a pain in the a$$... glue is difficult to spread thin and evenly before it starts to gel and then, after unclamping, the veneer laminate cups like crazy!

so, what do you guys that have built laminate selmers do when veneering?

any help is appreciated!

thnaks,
Miguel.

Craig Bumgarner

Miguel,

I've been using epoxy for laminating and have been very happy with it. Unlike water based glues like Titebond, hide glue, plastic resin glue, etc., epoxy does not hydrate the veneers and cause them to cup. Also, the open time for epoxy is much longer than any of the water based glues. Initially I thought it would be messy to work with, but with latex gloves and being careful to keep the glue on the wood (only), use just enough so it does not squeeze out all over the place, it is not bad at all. I use WEST brand epoxy, 105 resin and 205 (fast) hardener. 205 still gives you an open time of 45 minutes or more as long as you don't mix a whole bunch up in a pot. I'm usually mixing only an ounce or two at time. WEST sells pump kits which meter the mix, very handy.

Balancing the grain of the veneers also helps with warping of the finished laminate. If you are using four plys, this means two at 0 degrees and two at 90 degrees. For backs, I orient the two middle layers at 45 and -45 degrees from 0 degrees, if that makes sense. For sides I use 0, 90, 90, 0.

I do not use two parallel layers of the exterior cosmetic veneer together as I have seen suggested. This would be helpful if breaking through the first layer when sanding but would cause grain balance problems unless one goes to 5-6 layers. (If you figure out how to balance the grain with four layers oriented at 0, 0, 90, 0, let me know). I've not been willing to go to more layers because of the weight. (I'm rethinking that in light of Gore & Gillet, btw, saw your post to me in ANZLF, thanks!). I do wish 1/30th of an inch veneers were more common, they are much more forgiving when sanding than the modern 1/42th of an inch stuff.

I can't help you with the Brazilian, no experience specifically, but I would mention SuperSoft II veneer softener used for smoothing out veneers before pressing. I've used it and it works great to both smooth dry brittle veneers and make them softer for bending. SuperSoft is just sprayed on and allowed to dry for 24 hours before use. Supposedly the affect wears off in about 3-4 days and the wood returns to normal afterward.

CB

noodlenot

thanks for the tips Craig!

I now feel a it dumb, as i have a bottle of supersoft II in the shop and totally forgot about it...


cheers,
miguel.

Craig Bumgarner

Supersoft works good on wood bindings that are otherwise to bend too.

noodlenot

i was thinking of using two outer layers of 6 mm (i guess it´s equivalent to 1/42ths) and a middle one of 1 mm (maybe maple, as i´m having trouble finding poplar at 1mm). crossing them (and making it actually a ply) is a good idea, and now that you mention it, it was the way Selmer did it, right? i forgot about it and glued all 3 veneers long grain... grrrr...
regarding BRW - i think i´ll make a test piece with supersoft (actually i bough the SS II for ebony bindings and a heavily quilted maple set i have waiting). i was lucky enough to find a veneer dealer going out of business that has a lot of BRW veneer (and also some boards!!), so i took the plunge and bought a lot of it. They are from 10 cm to 18 cm wide, so i´ll have to make some joining. Some of them have lots of sapwood, which i really like - but not all folks do. If you want i can ship you of couple of them, no probs.

I´ll also search for that west systems epoxy, i believe i should be able to find it here, or at least in the UK.

once more, thanks!

cheers,
Miguel.

crookedpinky

I had a problem using Titebond when laminating ( too wet and messy ) I had much better results with Cascamite and using paper joining tape on the outside joins.

The cascamite is less wet and dries rock hard - the problem is making sure it's spread over the whole surface and then getting enough pressure on the whole thing to ensure a rigid structure.

A.

noodlenot

i never used cascamite and don´t know much about it, besides the fact that Jose Romanillos (a classical guitar builder) told me once he used it in the past.
is cascamite less aggressive for your health than epoxy?