Flint Miller
11-04-2010, 2:18 PM
To test a construction technique, I recently laminated a 16"x8" length of commercial veneer to a similar size I'd sanded down (rather unevenly) to 2-ply from a 1/8" veneered piece, using DAP Plastic Resin glue. The two pieces were curved longwise on about a 12" radius, and supported from behind only along the edges of the 16" dimension. They were clamped together using cauls running across the 8" dimension, with pressure applied only at the ends of the cauls--which if anything bowed out when clamped. In short, it seems unlikely that even 50 psi pressure was applied to the inner area of the piece, never mind anything like the recommended 175 psi for softwood.
I used plenty of glue, and excess was extruded all around. To check the effectiveness of the glue job, I cut the laminated piece into strips. Everywhere, the glue line was nearly undetectable, and there were no voids or pockets of glue.
So I'm wondering, if lower pressure is adequate to achieve this result, do I lose anything by not using higher pressure? Greater strength? Greater longevity? And why do UF glues generally stipulate higher clamping pressures than other glues?
L.F.Miller
I used plenty of glue, and excess was extruded all around. To check the effectiveness of the glue job, I cut the laminated piece into strips. Everywhere, the glue line was nearly undetectable, and there were no voids or pockets of glue.
So I'm wondering, if lower pressure is adequate to achieve this result, do I lose anything by not using higher pressure? Greater strength? Greater longevity? And why do UF glues generally stipulate higher clamping pressures than other glues?
L.F.Miller