Assuming a vaccum press can be considered a ‘tool’ …..
There has been some discussion with regard to the best, or at least prefered glue/adhesive to use in a vacuum press for laminating veneer. My project consists of resawing 8/4 cherry and laying it up onto a substrate, probably MDF but open to suggestions, would prefer to use plywood as it’s not as messy (dust & stuff)
I just finished building a vacuum press, not a bag setup – actually it’s more along the lines of a torsion box bed with some 20mil vinyl laid over it, 1″ runners around the perimeter of the 2′ x 6′ box surface, then the vinyl folded up and over these runners then the vinyl is clamped between cauls onto the runners to create the ‘vacuum chamber’. I opted for this type of design to ensure, or at least attempt to achieve a flatter end product having the top of this torsion box as a reference bed to suck the lay-up down onto.
OK – sorry for all that but just so’s you have the picture of the setup.
Thus far I’ve tried a couple of tests, successful I’m happy to say, using polyurethane (Gorrilla Glue). This because I used some old scrap plywood for the test which wasn’t very smooth (read CDX sheathing stuff -arghhhhh-). The GG did a good job of taking care of the anomolies in the plywood. But I’d like to use something that doesn’t require up to four hours in the press.
Stuff glued up with TiteBond can, so it says on the bottle, be taken out of the clamps after an hour’s time. Would it be safe to assume this would be true for veneer as well? I should mention that my ‘veneer’ is on the thick side approaching 1/8″ which will be planed and/or sanded down to a more appropriate ‘thinness’ once it’s all glued up. The finished product(s) will be used for cabinet doors and a mirror surround in our master bathroom. It was suggested before that hide glue might be a good choice other than the fact this is a bathroom, high humidity situation.
Thanks for any suggestions.
Replies
Dennis,
If you are gluing flat veneer onto a flat substrate, 1 hour in the press should be sufficient with titebond. I'd probably feel safer leaving it in a little longer if you are pulling the veneer around a curved substrate. You can get a feel for how things are going by taking a look at what the squeezeout is doing- if it still looks as wet as when it was laid up, I wait a little longer. Even on flat surfaces, I get a more uniform bond by putting a caul of some kind (1/4" ply, or even corrugated cardboard) between the veneer and the bag. Soften the corners of the caul so you don't pull a hole in the vinyl as it draws down.
Regards,
Ray Pine
Thanks,Ray
I've read your post a couple of times, so forgive me if I seem a little slow but I gather you are asking about adhesives and not just simply clamp time? If so, I prefer Unibond 800 for my veneer work because it has gap filling characteristics that mean you need less clamp pressure, it is tintable, has a long open time (important for veneering), and most importantly has low shrinkage. The shrinkage characteristic is really important for adhesives that you intend to use for veneering.
Sorry, TangoMike for the long preamble to the original question. Just watned to put all the cards on the table, so to speak.Yes, glue/adhesive type was the real thrust of the question. My vacuum setup is pretty low tech. I don't have a vacuum switch controller for the pump having put this thing together from stuff I've been able to scrounge. Thus I leave the pump running through the glue cure period. The pump itself is a heavy duty thing intended for continuous use so it's no big deal plus I have a bit of leakage in the setup so it's not being stressed out all that much. None the less, I don't like leaving things run all night in the shop when I'm not out there to monitor what's going on. I'll pick up some unibond and do some tests. It sounds like it will be a good solution in my case.Thanks for the input!
http://www.vacupress.com has a forum.
There's no new questions on the net, just new people asking the old questions so the answers are already out there.
"There's no new questions on the net"like most topics in woodworking, things don't change all that much so there really aren't many new questions to ask.
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