On Wed, 24 Nov 2004 10:37:18 -0700, Doug Winterburn
wrote:

The main cause of kickback is the rear of the blade lifting the workpiece,
and the higher the blade, the more vertical the rear blade motion.

That's a risk, but it's a risk that's easy to deal with. Over the
width of the blade it's balanced front and back, so the force your
hold-down needs to provide is much less than it would to resist the
unbalanced forward forces from a blade that's rubbing on the upper
portion of the blade.

It's also notable that rear-blade lifting doesn't cause kickback
itself, what it causes is lifting the blade into contact with the area
that does then kick it (admittedly by this point the blade will have
increased any skewing it might have, which also makes the drag worse).
I'd like to keep my timber away as much as possible from the really
dangerous area - the patch near the top of the blade where the forward
forces are largest.

If you have a kickback near-miss on a high blade, it's _very_ evident
that the blade starts to lift the timber with a small force, then may
(if you're unlucky) push it forwards with a much greater force. This
is another reason why low splitters aren't much use - if the timber
does lift off them, the timber closes up and suddenly grabs. I can
feel a small amount of drag before it's a problem and just hold the
timber down or kill the saw, but with a sudden impulse it's going to
fly before I notice.

I've had a bad week for kickbacks to be honest - it's near freezing in
the workshop and clearly the saw table has contracted. My fence is now
dragging and the tail end is going out of square unless I'm careful
about the setup.
--
Smert' spamionam