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Howdya do that
13th October 2007, 07:14 PM
I thought I would have a crack at veneering, just a small panel for a rail and panel box lid.

My intention was Black Heart Sassafrass (Spelling?) one side and Huon pine the other, about 220mm square, 9mm MDF as the base.
I started with the Black Sass, used AV140 glue and sandwiched it between two pieces of 18mm MDF with lots of clamps.
When I first took it out I was impressed BUT I went to do the Huon side today and the whole board has cupped inward on the veneered side:C.The board is about 2mm lower in the middle:C

Any suggestions as to where I have gone wrong:?

Fencepost2
13th October 2007, 07:19 PM
I had a similar problem when I glued 64 squares on one side of a board to make a chess board.

I think you need to treat both sides of the base board identically.

That is, glue on both veneers in one the one clamping set up.

weisyboy
13th October 2007, 07:51 PM
id say the moisture from the glue was ubsorbed by the MDF and then as it dryed then it shrunk.

DJ’s Timber
13th October 2007, 08:21 PM
Glue both sides in one go is the way to go

Lumber Bunker
14th October 2007, 09:05 AM
As the glue dires it srinks. you should do them both at the same time and you will have no problem.
Or you can do one side, clamp for 40mins (depends on glue) unclamp, do the other side and clamp again.

You should be able to save it, when you apply the huon, it will be cupped still but after clamping it may stay flat.

good luck ... next time

hcbph
14th October 2007, 09:51 AM
I'm not familiar with the glue you've referenced by name, but as I just did some more veneering today, here's my take. You want to put veneer on both sides of a piece to balance it out. I prefer to use Dap Original Contact cement for the glue and I like to apply it with a roller. Once I've put it down, I roll it with a veneer roller and I like to put into a press type clamp to insure it stays put.

Good luck on fixing you problems

Paul

AlexS
14th October 2007, 02:30 PM
What LB said. You'll find that when you do the 2nd side it will almost straighten out. AV 140 is fine for veneering, although I prefer AV180.

Howdya do that
15th October 2007, 08:37 AM
Thanks all,

I had a busy weekend with stuff other than woodwork. I'll glue the huon this weekend and see how it turns out.

Both sides at the same time in future:2tsup:

hcbph
16th October 2007, 10:53 PM
Thanks all,

I had a busy weekend with stuff other than woodwork. I'll glue the huon this weekend and see how it turns out.

Both sides at the same time in future:2tsup:

Remember if the panel is warped when you veneer it, it may hold that shape due to the veneering, if you're using thick veneer and use water based glue especially. If it's still warped or cupped prior to veneering the other side, try pressing it between two heavy boards, table leaves, whatever for a few days to help flatten it first. Remember glued up laminations, you can form them into a shape by gluing up pieces and put them in a form, same principle here except not as much material.

Paul