Iron-on Veneer With PVA

Scozza | Posted in Wood and Materials on October 22, 2006 07:16am

I’ve just used dried PVA applied to both surfaces in order to apply venner to an MDF substrate with a hot iron. My problem, however, is that the veneer had a tendency to shrink away from the joint, leaving unsightly gaps. Any advice? Thanks.

Replies

mufti | Oct 22, 2006 11:07pm | #1
I have ironed veneer to MDF but with sheet glue film which comes with a paper backing. It's not a water glue.

I guess your problem is the MDF is really dry, the veneer is not, and ironing one to the other results in drying of the veneer. You could try,on a scrap piece, dampening the surface of the MDF before ironing and keep the temperature as low as will work.
Rich14 | Oct 23, 2006 12:43am | #2
Scozza,

How did you prepare the veneer joint before you ironed it down? Did you joint the two edges and tape them or did you use the overlapping method?

Rich

Scozza | Oct 23, 2006 01:23pm | #3
Hi Rich,

Thanks for the reply. I tried both methods and found the same results. I did not moisten the A-side of the veneer and wonder whether this may have had an effect. It may have been the glue, itself. The veneer did curl considerably as the glue dried (unsurprisingly, I suppose). Any help would be greatly appreciated. Thanks.

Scozza

Rich14 | Oct 23, 2006 04:23pm | #4
Scozza,It's still difficult to understand from your description what happened.Here are 2 methods to get perfectly tight veneer joints with heat-activated PVA (or other adhesives).1. Joint both pieces. Iron the first piece down. (Or joint the first piece after it is down by trimming with a knife and straight edge. Warm the small excess strip to loosen it and pull it off).Butt the jointed edge of the second piece against the first with a thin dowel under the second piece about an inch away from the joint. Iron the second piece down away from the dowel, so that it is firmly adhered. Slide the dowel out, and iron the remaining part of the second piece down. The bulge caused by the dowel will cause the edge of the sheet to firmly press against the edge of the first piece as you iron the bulge flat (it will flatten completely).2. Iron the first piece in place. Overlap the second over the first at the intended joint line by 1/2" to 1". Iron the second piece, but don't get too close to the joint or you may split the upper veneer. Cut through both pieces with a knife and straightedge. Use a very sharp, thin blade, held as straight as possible. A utility knife works. I prefer a linoleum cutter. Lift the upper piece to get at the waste piece underneath. You may need to heat it to get it loose. Iron down the second piece.Rich