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Lloyd E. Sponenburgh[_3_] Lloyd E. Sponenburgh[_3_] is offline
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Default band sawing annealed 304 SS?

Ned Simmons fired this volley in
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Slow the surface speed.


nah... start with a sharp blade, and increase the down pressure.

There's nothing about 304SS in the annealed state that makes it hard to
cut, except this: If the blade "skates" (even a tiny bit), it work-
hardens the surface of the 304 to WAY beyond what a carbon blade can
handle.

Start in a fresh spot - never, EVER try to re-cut in a kerf that failed -
and keep enough down-pressure on the blade so that every tooth cuts the
whole width of the work.

And _that_ means you may have to go to a coarser blade, because if a
gullet fills up with chips, then it lifts off the work and skates. The
tooth pattern must be coarse enough to handle the entire chip generated
over the width of the cut.

There's benefit in a higher surface speed, because it makes each tooth
pass through the cut faster, thus taking off less metal per "stroke".

It's the same thing drilling the stuff. Strong, continuous down-
pressure, with fairly low surface speed for drilling by hand.

If you ever have to retract to clear chips, you must transition from
full-pressure drilling to retracting in one quick reversal, so the
cutting edges never, ever skate (idle is what the metal men call it) in
the hole. For the same reason as when sawing, you should clear chips
frequently to avoid the flutes' clogging and causing the chips to rub in
the hole.

LLoyd