Cupped Wood

[Bob Yarbrough]

Joining 3 pieces of 3/4 wood for a table top. One piece from one board, the other two from a different board. 1 curves up, 2 curve down. How do I flatten the thing? I do have a hand plane, but do I do the glue up and then plane, or try and find a friend with a power plane and thin up the top pieces and then clue up?

[Dennis McDonaugh]

Bob, I would flatten the boards before joining them together. How you go about it depends on what tools you have available to you. You need to joint the boards so one side is flat then plane them to thickness. It sounds like you don't have a power joiniter or planer. Is that correct?

[Bob Yarbrough]

correct! Those are biggies on the wish list.

[Bob Yarbrough]

Didn't update, know not why?!?

[Dennis McDonaugh]

Sorry Bob, I got sidetracked.

You can fix it with your handplane. Here's the rough steps

1. You have to joint one side so its flat, it doesn't have to be smooth but it has to sit flat on your bench and not rock so you can work the other side.

2. Work the high spots until you begin to flatten the top. At this stage you can work across the board at a 45 degree angle. Check your progress with winding sticks until you have a fairly flat surface. Plane with the grain as you get closer to flat. (winding sticks are simply two sticks with parallel edges that you sit on top of the board. The top edges will be even and parallel when the top is flat. They will show twist or bow in the board if it is not flat. Site across the winding sticks from the end of the board.)

3. Once the top is flat, strike a line all the way around the board at the thickness you want. Turn the board over and flatten the other side until it is even with the line.

Its not a hard process, but it does take some practice and it is a little more difficult with only one plane. To really do it efficiently you probably need a scrub plane, and a 5 or 7 and a 4 smoother.