Troubleshooting Expanding Veneer

What makes veneer expand overnight after application? Pros suggest possible causes and remedies. May 13, 2005

We are currently working on a large project that requires veneer to be applied after fabrication (post-veneered). We are using the dreaded contact adhesive. We veneer the panel, flush trim, and sand, and the next day the veneer has expanded 1/8"-1/4" beyond the extent of the fixtures. We have rolled/pressed the veneer extremely well. This problem is not isolated to one fabricator. 7 custom fabricators have had this problem. The species if pecan. We have had problems with pecan before. We are also laying up ash currently, and are having no problems whatsoever. The veneer is wood on wood. The shop is not climate controlled. Any help?

Forum Responses
(Veneer Forum)
From John Van Brussel, forum technical advisor:
I assume you are using a water based contact. If you are using a j-roller for pressure, stop. You need to use a shop built scraper or a veneer hammer. J-rollers do not give enough pressure for veneer. You may want to try FSV, which is a fast tack PVA which is applied similarly to a contact, except that you only have to coat the core.

From contributor F:
It sounds to me that you are not acclimating your components. Wood expands when it takes on moisture and shrinks when it dries. The suggestion to use FSV is also very good, as FSV will provide a rigid glue line while contact tends to be flexible. FSV responds well to the veneer scraper or hammer as well.