Best way to fix a cupped leaf on an old Oak dining room table.

how about rip the cupped leaf joint and re-glue? ross

Make several table saw cuts on the back side and along the length, at about .3/4" intervals, that cut slightly over 3/8" deep (assuming the leaf is 3/4" thick).

Fabricate 4 or 6 little cross braces to lag bolt across the width of the back. 1 on each end and 2 or four evenly distributed. Be sure that the cross braces miss the expansion rails of the table before deciding where the braces go.

You might want to tighten these braces a little at a time over a period of a couple weeks so as not to bust the board.

Good Luck, DoubleD

Is one side of the leaf finished and the other unfinished? If so, try removing the finish and then clamping it flat with boards running across the cup. It may just be out of balance due to humidity changes, this will let it equalize. Leave it in the clamps for a week or two and then see what happens.

If the table isn't finished on the underside, then it's wanting to cup right now too, but structure of the table is preventing it. Remove the finish from the top and let it sit for a week or two before you take it off the supporting structure.

When you refinish, make sure you apply the same finish to both sides.

-Leuf

if you choose not to rip and re-glue and go with the clamp method, if the under cup side is not finished moisten with water this will cause the wood to expand on one side. you will have to take a little time and may have to reapply a couple times to let the water soak in a little this works, iv'e done it ross