On 3/19/2015 12:15 PM, Larry Blanchard wrote:
On Wed, 18 Mar 2015 17:00:58 -0700, Electric Comet wrote:

SS destrroys the blade when deployed?
didnt know that

It works by firing a block of aluminum up into the blade. It'd take one
heck of a sturdy blade to survive that! Even getting the block of
aluminum off of the blade is a bear.



Ok, to be completely honest as to how this works the aluminum block is
not fired. It is under spring tension and held in place by a fusable
link. When the machine detects skin contact an electrical charge is
sent to melt the fusable link and the spring pushes the aluminum part of
the brake into the blade. The rotation of the blade does the rest, it
naturally cuts and jams into the block like it would into a piece of wood.

I have yet to see a blade destroy itself after this event, and I have
seen it happen many times in demonstrations. Certainly the blade is
damaged to some extent and may certainly not be worth repairing but is a
far cry from being non survivable or destroyed.

There are several pictures here of a blade that was used in the test. I
don't see anything wrong with the blade but I certainly would want it to
be checked out before returning it to normal use.

http://www.newwoodworker.com/reviews/sawstop2.html

If you google sawstop blade brake and click on images there will be
numerous images of blades imedded in the brake and and after the brake
was removed. None that I can see is even missing a carbide tooth. But
again I would certainly want to have the blade checked out before reusing.

Now having said all of this the force of the motor is gone when the
blade drops and the brake trips so I am certain that this minimizes
damage to both the blade and brake.


And from the expert advice at the SawStop FAQ web site,

Can the blade be reused if the safety system brake is activated?
When the safety system activates, it will often damage one to two teeth
on the blade. It is usually cost-effective to have high-quality blades
repaired by a qualified blade sharpening service. However, less
expensive blades should be discarded.