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J. Clarke[_2_]

In article ,
says...

On Wed, 13 Oct 2010 11:37:59 -0500, -MIKE-
wrote:

On 10/13/10 11:22 AM, Bill wrote:
-MIKE- wrote:
On 10/13/10 7:44 AM, Markem wrote:
On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

I suspect that a small pyrotechnic pressurizing one of the calipers off
my '76 Lincoln might surprise you.

Yes but the heat will do what to the saw blade?

Mark

Nothing.
A lot more heat is generated by cutting than would be generated in the
half second it would take to slow down the blade.

You guys do realize we're not leaving the motor on in this scenario,
right? :-)

Yep, thought of that. Gotta break the problem into parts (important
trick/secret!) : ) I didn't count the mass of the rotor either, or it's
attached parts, in my other post either. I'm curious now though about
the calculation (foot/lbs of force).

Bill

Sometimes all it takes is a couple of scraps of wood to show how
"little" force is needed. Haven't you ever stopped a coasting blade with
a scrap of wood?

I still see people talking about the SawStop and what it takes for an
emergency stop of the blade. I don't know about anyone else, but all I'm
talking about is a convenience stop.
I suspect a blade could be stopped (at shut-off) in less that a second
with something the size of a bicycle brake and a spring.

Use a DC motor and a DPDT switch with a big resistor across the "stop"
terminals to short the motor when you shut it off. Stop a 10 inch
blade from 3600rpm in less trha a second with a dead short (if the
switch can handle it) or in about 2 seconds with a good "soft" braking
resistor.

Which is where this thread started.