drawer front warpage

[Bob Cooper]

Just finished the drawer fronts for my first vanity. They are Alder and are about (memory) 5/8 thick. Everything was nice and flat when i glued them up. After that i put a nice edge on them, 3 coat of oil based poly and then went to attach them tonight. A couple had warped some. The biggest (9" wide...i know this is wide for a drawer front w/o doing stiles and rails) cupped.

I know this is a basic question but how do you prevent this? i only put poly on 1 side and i'm curious if this is much of a factor. The boards that were used were about 5" wide so all but the smaller drawers were made from 2 joined boards.

A few other factors:

• i live in SC but i noticed the warpage before i brought the wood into the house (so humidity didn't radically change).
• the entire process for joining, planing and glueing and then replaning happened relatively fast -- 2 evenings (fast for my typical projects).
• the fist coat of poly (50% thinned) was put on probably 4 days later and it took 3 days to get the 3 coats on.
• I noticed the warpage when i went to install them, then day after the last coat of poly was applied <-- the warpage could have been there for a while though.

I'm sure i need to read up on wood characteristics but any pointers are appreciated.

[Jim Becker]

Bob, if these drawer fronts are "false fronts" and going on the front of a complete drawer box...the process of fastening them will flatten them out. And yes, I do suspect that prefinishing on the front (and presumably edges) will have caused the issue you describe.

[Brian Jarnell]

Always seal both sides otherwise you will tend to get movement.

[Bob Cooper]

ok..thanks. i thought that may be the case.