This is a hard one to believe, but I think I've found the cause....
I was building a new sharpening station yesterday (pics on ABPW, btw) when
it happened. Just finished the last rip from some 1/4" ply for drawer
bottoms when WHAM... the off cut flew out of nowhere and hit me hard just
below the beltline. Then, the damn thing bounced off me, flew under the
blade guard, hit the blade again, and WHAM, this time it nailed my arm which
I'd just put down around the first wound.
I powered down and unzipped to check my gut, it's definately gonna leave a
mark. There actually a 1/2" hole in my blue jeans where the corner of that
1/4" ply hit me, and a large welt on my arm where it hit me again.....
OK.. time to stop and figure out WTF just happened. I have a new 3hp Jet
cabinet saw that was been an absolute joy. Recently, I fitted it with an
Excalibur overhead blade guard with DC which, by the way, was in use during
the cut. The piece of ply was 24" by 20" or so an I was ripping 4" off the
20" side. Only one hand was on the stock, so I didn't bind the blade. But
what the #$%^ happened???
Well, I was starting to ache badly, my side and arm, so I opened up a beer,
(and another, (etc...) and pondered this for a while. My technique was
fine, guard and splitter were in place. What caused this?????????
My best theory is that the off cut was actually pulled off the table and
into the blade by the suction from the dust collection on the blade guard,
which caused the kickback. It didn't take long (another beer) before I
unplugged the saw, fired up the DC and started "testing". Going through the
motions of the last cut, I discovered that the suction from the DC, when the
guard was lowered fully to the table, was enough to pull up my ZCI. It
didn't pull it completely out from the saw throat, but it could pull it up
enough for the blade to catch it. The DC also had enough suction to pull
pieces of the 1/4" ply up off the table, even though the guard was 1/2" or
more above the ply. I didn't get very scientific with this test, and by
that time I was under the influence, but the conclusion is the DC surely can
pull stuff off the table and into the blade. Oddly enough, this experience
happened to someone who is in no way accustomed to using a blade guard at
all, let alone one with built in DC. I've a nice welt on my arm, and a good
sized black and blue mark on my gut from this. I'm certainly gonna continue
using the guard, and the DC, but I think the DC certainly will not be used
for thinner or smaller materials. Anyone else have an experience like