Wood veneer bonding

I want to bond some hot glue backed wood veneer to epoxy coated wood at the thwart-inwhale gusset on a SOF canoe. I'm thinking hot melting it then epoxy encapsulating. What say you?

Dino

 

It depends on the "hot glue" formulation. I would think this is the typical heat activated glue (iron on veneer sometimes called hotmelt), rather then a hot glue and these are usually, PA's and very compatible with epoxy. Some veneers use an EVA which isn't the best choice as it may have bond issues with epoxy, but more importantly might "creep".

I've used veneers many times and usually avoid adhesive backed stock and just use epoxy.

Epoxy encapsulation, after you've ironed the veneer on, seems logical too.

 

This is not relevant, but I used to make curved marquetry things and would glue them up by spreading titebond glue on both sides of all the veneers, except the face and back, then let them dry. I would then put the layers on a form, stacked like plywood with the marquetry on the outside, wrap it all with a long strip of elastic and microwave it for x amount of seconds. After it cooled, it was done. It can be done in an oven also or with a heat gun, but the microwave concentrated the heat in the glue and not so much on all the wood.

 

PVA's (TiteBond) and EVA's are similar and both can be heat activated, though EVA's are better formulated for it, but both tend to creep, which can be a bad thing with inlay or tight edge veneer work.

If the corrective panel above was my work, I'd be inclined to bag it down with epoxy, using a "naked" veneer. It's probable you can remove the hotmelt glue with a planer, though suspect some knife build up.

 

I recently did some veneering in a place where it can get wet and I used paper backed veneer. First I stained it, let it dry, and then coated the stained surface with two coats of epoxy. Then I flipped it over and sanded the paper on the back side to cut the paper's smooth finish, thin down the paper and insure that the epoxy would soak all the way thru to the wood. The only other trick was to be sure you applied plenty of force to flatten the veneer on the surface. I vacuum bagged it, but it also worked a lot better with a platten on the front surface to make sure the veneer didn't "potato chip" and laid flat.

I was afraid the paper would get wet and the whole thing fall apart if I didn't get it totally soaked with epoxy. Being a dark wood I was also afraid that in bright sunlight it could get hot enough to debond, so I stayed away from heat activated glues. I was comfortable that it won't peel of ever, and it looked great.

Had to redo one surface that I didn't use the platten on, but that was the biggest "lesson learned".

 

Here's how it looks finished using the veneer hot melt glue backing on an epoxy coated surface. Only time will tell now.

Dino

 

I never use "backed" veneers, having had bad durability in the marine environment. I have backed my own veneers with cloth and epoxy, but this is a different story.

 

I like the 'whale tail' look.

 

Is that one of Platt Monfort's Geodesic Airolite designs?

 

Yes, and here is a link on the completion.
http://forums.wcha.org/showthread.php?11344-SOF-completion&p=58432#post58432

Dino

 

Very nice, looks light and fast. The geodesic roving was an unmistakable clue . . .