Thread: Getting rid of "cupping" on a pine laminated benchtop

G'day Greg.
Cupping is caused by one face being wetter than the other.
the "wet" side will bend around the "dry" side.
Turn it upsidedown and leave it for a week or two.
if this doesn't do the trick, you may have to seal the "wet side" with an oil based finish, then leave it to equalise and level out.
If you have or can borrow a moisture meter test both sides to see if there is any difference.
Sanding or thicknessing will seem like a quick fix. But the cupping can return.

Thanks Trevor,

It was also suggested that I bunch up some wet newspaper and lay it in the "dish" to add more moisture to the dry side.

If I eventually get the top flat, how can I stop the cupping happening again?

Regards
Greg

If you do the wet paper, you are only postponing the return of the cupping.

Once it levels out, seal it with a good polyurethane finish on all faces, sides and ends.
Also, try not to get one face wetter than the other.

Thanks Trevor

Best thing to do use a couple of planes, start with a scrub, then a jack , then a jointer. Work at the high spots first and across and diagonally, very easy to do. Then use a sander to finish off.

I have recenly done this with my bench which had been left outside while I was building the shed last year and the top cupped, it had been rained on, left in the full sun, etc. (I was also foolish and only sealed one side wen I was making the bench).

It is now perfect and I sealed both sides with a mix of poly and linseed. It has worked for me, I hope this helps. Adding moisture to a dry bench top is asking for problems, you are just avoiding the inevitable.