Truing-up rough wood

Planers will not remove the bow from rough stock; jointing is required before boards can be properly thicknessed. February 13, 2001

I just bought a thickness planer and wood in rough. I have planed the faces of some red oak with pretty good success, but am having problems with squaring up the wood. If I position the wood face up and sight down the side (narrow and un-planed), there is a definite bend in the stock. I tried to pick the pile the best I could to eliminate this. How do I get rid of the bend in the wood?

I have a poor man's jointer which essentially is a fence that I made for my router table and a straight bit. I can get a decent edge on it, but the bend remains. I have tried the table saw but that isn't working.

Forum Responses
A surface planer is not designed to straighten a piece of stock. I recommend the purchase of a jointer.

Squaring rough lumber

1) Using the jointer, joint one surface (the large flat part of the board) straight, smooth and true. This will give you a straight and established surface from which to work.

2) Surface the board to thickness observing the direction of feed in relationship to the grain, so you prevent chipping. This will make both large surfaces of the board parallel, straight, smooth and true.

3) Joint one edge of the board by placing one of the smooth surfaces against the jointer fence that has been adjusted to a perfect 90 degree angle to the bed of the jointer. This will make the edge of the board straight, smooth and true and at 90 degrees to both large surfaces of the board.

4) Rip the board to width plus one sixteenth of an inch to allow for a final pass on the jointer. This ripping cut will make the second edge of the board parallel to first edge.

5) Make one and only one final pass on the jointer along the edge that was cut by the saw during the ripping operation. This will make this edge straight, smooth and true and at 90 degrees to the large surfaces of the board.

6) Square the better end of the board.

7) Cut to finish length.

Process all boards that are going to fit together in the same setup of the machine to assure maximum accuracy.

The first thing I do is rip and cross cut each piece close to final size. This will relieve any internal stress the wood has first, so when you straighten it, it STAYS straightened.

To eliminate bow or twist in the work piece, it has to be cut out. If the wood is dried and conditioned correctly, it is usually much easier to work with. I would first locate a high quality (not necessarily a high quantity) kiln operation. This would remove a lot of the problem. A note--this is a common problem faced in the wood industry.

If your quantity allows, using a straight line rip saw and then moulding the part through a four-sided moulder would help. Just remember that you can not make steak out of hamburger. The material has to be able to be squared.

Dave Rankin, forum technical advisor

You may want to over cut by 4" - 5" in case you have any snipes from your planer. These can be eliminated in the final cut after planing.

For years before my shop had space for a good jointer, we used a fence made from 3/4 plywood and a circular saw to straighten our lumber. The only saw I know that is heavy enough to do so is a worm drive Skill brand saw. Just clamp the board to the fence and then run the saw down the fence.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
I have used a method similar to the circular saw method, only using a router and a top bearing bit. I use a smooth, straight piece of stock clamped to the top of the rough stock, allowing the router bit to take a small cut at the widest points. I simply re-position the guide for more small cuts until I have a straight, square edge. This works for any length up to the length of the guide, but is limited on the stock thickness by the depth of the cut of the router bit. I finally bought a jointer, though.