On Wednesday, August 28, 2019 at 7:36:26 PM UTC-7, pyotr filipivich wrote:
Greetings

Been having trouble with circular saws. I have a Skill 5150, which
works well "for some values". Specifically, the saw blade will bind
and start to spin.

There's a double-D pair of flats on the shaft, that engage the retaining/
clamping flange so blade torque can't loosen the screw?

If the retaining screw and flange can tighten down onto
a zero-thickness blade, it has plenty of pressure against the
thin blade, I suspect. But, that requires the
shaft and flange have enough engagement. It should be easy to test
(and don't forget, a bit of sawdust in the blind hole that retaining
screw goes into, can also get in the way).