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View Full Version : Purposely Cutting a Bow into a Board on the Table Saw



Richard Daugird
03-20-2024, 3:52 PM
Ya know how when you rip a long board with a bow in it, the bow follows the fence and you still have a bow? Any way to PUT a bow in a straight board, kinda the opposite?

George Yetka
03-20-2024, 3:59 PM
An extremely large circle template on a router is the first thing that comes to mind. Everything I can think of on the TS seems too dangerous

Patrick C Daugherty
03-20-2024, 4:08 PM
I would mark the curve on the board using a batten and cut it with a band saw or jig saw. Drawknife and spokeshaves or circle plane are also options

Maurice Mcmurry
03-20-2024, 4:12 PM
Ya know how when you rip a long board with a bow in it, the bow follows the fence and you still have a bow? Any way to PUT a bow in a straight board, kinda the opposite?

Using a bandsaw or jigsaw would be safer. Cutting to a line freehand on the table saw is generally considered a no no. It can be done if the curve is very slight. A hand held circular saw works and can create a tighter curve although a bandsaw or jigsaw is better. Inducing a bow into a board by bending it while you apply clamps and hold downs as you put on a slider or sled is an interesting idea. It would have to be a narrow, bendable board.

Cameron Wood
03-20-2024, 7:43 PM
Yeah, a circular saw works OK. I'll free-hand rips on the tablesaw & might do a very slight curve, but generally you push the first half then walk around to pull the rest, so it can't be binding then or the board will take off.

Lee Schierer
03-22-2024, 7:11 PM
Depending upon how long the board you want curved, how much curve and how much space you have in your shop you can use make as long a radius as you have room for use a circle cutting jig. They are quite easy to make.
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I definitely don't recommend the curve cutting free hand on a table saw.

Jamie Buxton
03-23-2024, 11:33 AM
For a while, there was a circular saw blade intended to cut curves. It was shaped kinda like a triangle. Here's video: https://www.youtube.com/watch?v=KQ-P4ngnj8w

Richard Daugird
03-25-2024, 9:57 AM
That triangle saw blade is crazy. Funny thing, I am wanting to cut a cove in a cedar slab that I am using to make a bench seat, and was thinking I could use a hand circular saw sideways like in the video.

Zachary Hoyt
03-25-2024, 10:20 AM
You can do the sideways cut with a circular saw with a regular blade too, though you can't take that deep of a cut in a single pass. When I was 16 or 17 I saw a carpenter do that to shave a bit off a high spot when installing a sliding glass door, and have done it since then when it seemed advisable. I was only there to help pick up the old doors that were being replaced, so I was lucky to get to see that method.

Carl Beckett
03-25-2024, 10:53 AM
When I have wanted to make shallow curves in a piece, I have used a thin strip of plywood (say 1/4" plywood) that I compress using a string or clamps. This 'bows' that strip which I then use to mark the piece.

Once the piece is marked it becomes a combination of handheld jigsaw, bandsaw, hand plane/spokeshave, and spindle sander to smooth it out. Sometimes I will glue a piece of sandpaper to a section of the plywood which allows it to flex - that creates a uniform profile.

I did once setup a center pivot on a stand a few feet out from my bandsaw. Clamped the piece to a sacrificial board. Then it becomes an arc as part of a circle jig and can do multiples.

Can not think of any rational way on a TS.

Lee Schierer
03-25-2024, 11:11 AM
That triangle saw blade is crazy. Funny thing, I am wanting to cut a cove in a cedar slab that I am using to make a bench seat, and was thinking I could use a hand circular saw sideways like in the video.

You can cut pretty nice coves safely on a table saw with a jig, though they do take quite a bit of time to make the cut. Clean up can be a bit of work if you don't have some raker teeth on your blade.

Richard Daugird
03-25-2024, 12:11 PM
I have cut coves with the table saw, I was just thinking, since my bench is about 5' long, I'd try a hand circ saw. Would not cut as big a radius though.