Straightening boards on the tablesaw
With a couple of simple modifications, you can turn your tablesaw into a jointer for straightening a bowed edge on a board. As shown in the drawing, begin by screwing a wooden auxiliary fence to your saw fence. Next, raise the blade so that it clears the thickness of the wood you want to straighten. Now bring the saw fence up to the blade so that the teeth just touch the wood. Using some two-sided tape or small brads, tack a 1/8-in.-thick strip of hardboard or wood just behind the blade.
Now carefully run the curved board through the saw with the concave side toward the fence. The section of the wooden auxiliary fence in front of the blade acts as the jointer’s infeed table. The 1/8-in.-thick strip behind the blade acts as the jointer’s outfeed table. By making multiple passes, you can straighten just about any badly bowed board with this method.
— Brian Everest, Nelson, None
Edited and Illustrated by Charles Miller
From Fine Homebuilding #165
Five years ago I showed a homeowner how to straighten nine foot planks of cherry that was in a barn loft for over 60 years by building a twenty foot long bed with his table saw in the middle. The sawing technique was to run the concave side of the plank against the fence while sawing the convex side,then resetting the fence and running the straightened edge along the fence while cutting the points off the concave side. the planks were re-sawn to 4/4 and run through the planer to 3/4, then pieces cut to size to trim out his remodeled house.
This is NOT a safe method. Make a "table saw ripping sled" (not "cross-cut sled") of which there are many designs on the Internet. Everything from designs that require $10 of hardware and take 10 minutes to put together, to much more elaborate sleds are available. Easy peasy.
Why do you think this process is unsafe?
Just screw or nail a straight board to the curved one. Use the straight board against the fence doesn’t really matter where you screw the straight board to the curved board once you run it through the saw take off your screwed board. Then run the new straight edge against the fence. And you now have a straight board
The amount of time it would take you to clean up the concave side of a board on the tablesaw in this manner could be used to clean up a dozen boards with a simple skil saw, and done much better. Then take it to the tablesaw to straighten your convex side, then, simply flip it over and skim over your skil saw side. You and guys like BobboMax is what give tablesaws a bad anomaly, when that blade catches and slams that board back in your head, or through your chest, you'll understand why that isn't a safe method. Emergency rooms have an entire list of guys like you that have been doing these kind of idiotic procedures on a tablesaw for years and never had a problem.......