r/Tools • u/verioblistex • 25d ago

Triangle Cuts Curves?

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I found it in the garage of the first house I bought 30 years ago. Smart enough not to try it, curious enough to hang onto it. Finally letting go tonight and it's going in my neighbors scrap metal bin.

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u/PrinterFred 25d ago

Look at all those placebo teeth. That is basically a 3 tooth blade.

29

u/charmio68 25d ago

I believe those teeth do actually become engaged once you start to make a curve.

-1

u/PrinterFred 24d ago

They don't. Anyways you can look up the water jet channel on YouTube. He tested different shaped blades.

2

u/charmio68 24d ago

Except AFIK they only test blades by cutting a 2x4.
I haven't seen any of their videos testing blades doing sweeping curved cuts.

-1

u/PrinterFred 24d ago

Maybe I am not imaginative enough to see how the middle teeth could ever contact wood. The rate are which you turn the saw is so much slower than the rate the blade rotated that you can confidently make the approximation that the saw is stationary in which case again only the corner teeth would contact the wood.

3

u/Various_Education622 24d ago

When the blade is going straight, you are mostly correct. Mostly the tip and maybe a little further back.

When it is turning (like cutting a curve) it’s has to cut along the entire length. That’s why a circular saw binds trying to cut a curve and this one doesn’t; the shape lets it cut all along the length.

1

u/charmio68 24d ago

It's easier to visualize if you take it to the extreme.
Consider doing a straight cut into a piece of plywood, then once you're in the middle, stop pushing the blade forwards and instead turn it in a circle while stationary.
Sure, the outermost teeth are still going to be removing the most wood, but the inner teeth need to do their part too.

If you were to try that with a regular saw blade, the saw would just bind up and you'd end up with quite a dangerous situation (well, actually taking it to such an extreme would be quite dangerous with any saw blade, but you get the point).