squaring bowed wood

Let's say you have a long board that has a bow to it - nothing huge but maybe 1" deflection over 8 feet on a 6" board. How would you remove that bow? I'm thinking about it and wonder, because you don't have a straight edge to use as as reference point, removing the bow with a bandsaw or tablesaw seems terribly wasteful, but bending a 6" board doesn't seem possible.

Reply to
Eigenvector
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I would probably make two 4' boards out of it and remove the bow that's left with a handplane or my jointer. That's why I buy rough wood. The extra thickness will allow you to straighten the board.

Reply to
Lowell Holmes

That's why you have the longbed jointer... :)

It's either straighten the board if you need the full length or use shorter sections of it so the waste isn't as much. That's woodworking...

If, otoh, it was a 1x fascia board or something similar, and construction, not "woodworking", it would be quite possible in many circumstances to nail it in place on one end and spring it into alignment as one worked one's way along the length. Much depends on the circumstances...

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Reply to
dpb

Well I guess that answers it. For small bows, smooth them out, for big bows, smaller boards.

Reply to
Eigenvector

Okay, that would explain why rough is not sold in specific thicknesses - it gives you some room to play with.

Reply to
Eigenvector

Bending out a 1" deflection over eight feet on a 6" board is nothing. You think the planks on a boat grew bowed? The necessary bending on those is/can be measured in feet for a middle size boat. Now, if you meant crooked rather than bowed, that's a different thing.

Reply to
dadiOH

Well, there's always the chalk line and bandsaw method for edges. Superior to any tablesaw jig I've ever used at safely getting things in the ballpark.

The hand plane guy takes the convex part down to a snapped line, the jointer guy takes the concave part, runs two ends then the entire. Or, if he's one who thinks a long-bed jointer is magic, he might try to hack the whole thing at once.

If you're talking the face of the board, which I didn't read, but others did, there are three letters that cover getting a straight board - SOL. Set it aside for short pieces. Yet another reason for sighting your lumber prior to preparation. It keeps you from hacking up something straight for small stuff and trying to use something bowed at full length.

Reply to
George

I think you mean "crook" rather than "bow", i.e. the curve is in the same plane as the widest dimension of the board. What I do is temporarily attach another board with a good straight edge to the crooked board, so that the straight board can ride against the table saw fence. (A length of plywood with the factory edge makes a good straight edge for this use) Position the 2 boards and the saw fence so that the crooked edge can be ripped off. Then remove the straight edge, flip the crooked board over so the just-ripped edge can ride the fence, and rip off the other crooked edge.

I don't jave a jointer, but even if I did I believe I would still use this method for an 8 ft board that had 1" of crook to it.

Reply to
Larry W

Yes, crook is what I meant - thank you. I can see how what you do would work. Attaching a known quantity to the board for reference marks so that you can run it through the bandsaw or tablesaw with minimal waste.

Reply to
Eigenvector

We pretty much knew from your description what you meant. Basics, if you're interested in precise terminology, are bow, cup, twist and crook. Good stuff at

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if you're curious as to the nature of wood and why it does what it does.

With a tablesaw setup on a large board you're actually creating a larger, more unwieldy board by jigging. Lot easier and safer to snap the line and bandsaw for reference.

Reply to
George

If I didn't need the whole 6' in one piece I'd cut the board into two and thus minimize the loss due to the bow.

Reply to
Larry Blanchard

And if I did, I'd probably select another board... :)

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Reply to
dpb

Oh man, I'll be reading that for about a hundred years. Print it out and stick it in the shop.

Thanks again.

Reply to
Eigenvector

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