Winston writes:

The unconstrained tip of the blade is in the air above the workpiece
most of the time. That is the bit that waggles laterally, causing
binding inside the kerf.

I recall encountering this with a carpenter's saw cutting wood. The
solution there is to slow the stroke rate. Is there any way you can
do that with your sabre saw? I suppose if you put it on a rheostat,
it would either fry or not run at all. Or not?

--
Mike Spencer Nova Scotia, Canada