You must be a controls or P&C guy with WNH!


wrote in message
...
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.

The electornic way would be so much gentler and easier to implement. They
work like a charm.

Maybe only because of the background of the guys proposing it.


"J. Clarke" wrote in message
in.local...
Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

On Wed, 13 Oct 2010 18:34:56 -0400, Bill wrote:

J. Clarke wrote:
In , says...

J. Clarke wrote:

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

Bill
When it snapped (seriously)? I'm not an engineer, so I don't know for
sure. I just wouldn't be surprised. Maybe someone else can opine.

J. Clarke
Why would something that can stop a 4000 pound car "snap" when called on
to stop a 3 pound saw blade?

Bill
"Pyrotechnics" rather than a master cylinder with brake fluid?

J. Clarke
To stop the saw in a fraction of a revolution, you need rapid
application. A pyro will build pressure rapidly.

That is what I what I might expect to increase the probability of failure.

Given blade radius and density, and rpm, you could probably integrate to
compute the (foot-pounds of) energy that need to be stopped in a small
fraction of a second (I hope that the dust on the blade won't be an
issue). I've seen you post in another "forum" so I believe you are
up to the calculation. I do not have engineering background to back me
up, I'm just thinking it through with you and everyone else who is
reading. Evidently, you'll need to generate the equivalent of an equal
and opposite amount of energy. This means, I think, that you only get
the benefit of a "projection" (dot product) and not all of the force you
can apply to the side of the blade. My reasoning could definitely be
off, maybe a physicist or engineer could help out?

Disk brakes work by friction. The energy comes off as heat. Apply F to
the brake, k * F is the braking force where k is the coefficient of
friction.

Back of the envelope it looks like the Lincoln brake at Lincoln pressure
can stop it in about 1/3 revolution. Don't know how much higher
pressure that caliper can take--at 2x the pressure might be able to do
it in 1/6 revolution, which puts it in Sawstop territory.

Interesting. Thank you. I'm not sure about your "imposter"..

Bill
This is all assuming a clean blade for the proper high co-efficient
of friction.
Dust od sap build-up on the blade can change that very quickly.

On Wed, 13 Oct 2010 19:22:05 -0400, "Josepi"
wrote:

You must be a controls or P&C guy with WNH!


wrote in message
.. .
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.

Nope, just an ex-mechanic wire-head.

On Wed, 13 Oct 2010 18:15:40 -0400, "J. Clarke"
wrote:

In article ,
says...

On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

In article ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, Bill wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

But would also be totally impractical on a 10" saw.

Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

As I stated posters seem to lean towards the technology they are comfortable
with.

The mechanics would be a nightmare to me, also. To others the electronics
would be a nightmare.

Contactor and resistor?...way too complicated.


wrote in message
...
You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

In article ,
says...

On Wed, 13 Oct 2010 18:34:56 -0400, Bill wrote:

J. Clarke wrote:
In , says...

J. Clarke wrote:

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

Bill
When it snapped (seriously)? I'm not an engineer, so I don't know for
sure. I just wouldn't be surprised. Maybe someone else can opine.

J. Clarke
Why would something that can stop a 4000 pound car "snap" when called on
to stop a 3 pound saw blade?

Bill
"Pyrotechnics" rather than a master cylinder with brake fluid?

J. Clarke
To stop the saw in a fraction of a revolution, you need rapid
application. A pyro will build pressure rapidly.

That is what I what I might expect to increase the probability of failure.

Given blade radius and density, and rpm, you could probably integrate to
compute the (foot-pounds of) energy that need to be stopped in a small
fraction of a second (I hope that the dust on the blade won't be an
issue). I've seen you post in another "forum" so I believe you are
up to the calculation. I do not have engineering background to back me
up, I'm just thinking it through with you and everyone else who is
reading. Evidently, you'll need to generate the equivalent of an equal
and opposite amount of energy. This means, I think, that you only get
the benefit of a "projection" (dot product) and not all of the force you
can apply to the side of the blade. My reasoning could definitely be
off, maybe a physicist or engineer could help out?

Disk brakes work by friction. The energy comes off as heat. Apply F to
the brake, k * F is the braking force where k is the coefficient of
friction.

Back of the envelope it looks like the Lincoln brake at Lincoln pressure
can stop it in about 1/3 revolution. Don't know how much higher
pressure that caliper can take--at 2x the pressure might be able to do
it in 1/6 revolution, which puts it in Sawstop territory.

Interesting. Thank you. I'm not sure about your "imposter"..

Bill
This is all assuming a clean blade for the proper high co-efficient
of friction.
Dust od sap build-up on the blade can change that very quickly.

But we don't know which way it changes. Brake pad material isn't all
that high-friction you know.

In article , says...

The electornic way would be so much gentler and easier to implement. They
work like a charm.

Maybe only because of the background of the guys proposing it.

If it "works like a charm" then why can't it slow a dado fast enough to
meet EU regulations?

"J. Clarke" wrote in message
in.local...
Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

In article ,
says...

On Wed, 13 Oct 2010 18:15:40 -0400, "J. Clarke"
wrote:

In article ,
says...

On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

In article ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, Bill wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

But would also be totally impractical on a 10" saw.

Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It works reliably on a tilting Lincoln wheel in the path of rain, road
dust, and whatever else mother nature can throw at it, so why does a
nice, dry saw cabinet present such problems?

Do yourself a favor, pull a wheel off your car and _look_ at the
mechanism.

In article ,
says...

As I stated posters seem to lean towards the technology they are comfortable
with.

The mechanics would be a nightmare to me, also. To others the electronics
would be a nightmare.

Contactor and resistor?...way too complicated.

So tell us how to wire an induction motor to make the "contactor and
resistor" work.


wrote in message
...
You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

wrote:
This is all assuming a clean blade for the proper high co-efficient
of friction.
Dust od sap build-up on the blade can change that very quickly.

Consider what a disk brake caliper has to overcome: dirt, water, oil,
pigeons. It still does a pretty good job.

wrote:

Why would it be "impractical on a 10" saw? The brake rotors on that
car are IIRC 11.5 inch diameter and the whole brake assembly fits
inside a 15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

You want to put that goober under a car where it has to contend with dirt,
water, oil, ice, salt, road-kill entrails, and have it work reliably???

Common sense says it won't work and can't be made to work. Don't believe
your lyin' eyes.

On Wed, 13 Oct 2010 22:52:34 -0400, "Josepi"
wrote:

As I stated posters seem to lean towards the technology they are comfortable
with.

The mechanics would be a nightmare to me, also. To others the electronics
would be a nightmare.

Contactor and resistor?...way too complicated.


wrote in message
.. .
You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It's BECAUSE I was a mechanic for several decades that I would NOT use
a brake caliper for the application.

On Wed, 13 Oct 2010 23:16:27 -0400, "J. Clarke"
wrote:

In article ,
says...

As I stated posters seem to lean towards the technology they are comfortable
with.

The mechanics would be a nightmare to me, also. To others the electronics
would be a nightmare.

Contactor and resistor?...way too complicated.

So tell us how to wire an induction motor to make the "contactor and
resistor" work.
On an induction motor the process is a bit different. Instead of a
resistor across the motor to stop it you use "DC Injection" - in other
words throw about 40 volts DC across the winding for about 2 seconds.

On Wed, 13 Oct 2010 23:15:27 -0400, "J. Clarke"
wrote:

In article ,
says...

On Wed, 13 Oct 2010 18:15:40 -0400, "J. Clarke"
wrote:

In article ,
says...

On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

In article ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, Bill wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

But would also be totally impractical on a 10" saw.

Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It works reliably on a tilting Lincoln wheel in the path of rain, road
dust, and whatever else mother nature can throw at it, so why does a
nice, dry saw cabinet present such problems?

Do yourself a favor, pull a wheel off your car and _look_ at the
mechanism.

I've been doing it for over 45 years
I've also rebuilt a few tilting arbour saws - both belt drive, gear
drive, and direct drive..

On Wed, 13 Oct 2010 22:25:01 -0500, "HeyBub"
wrote:

wrote:

Why would it be "impractical on a 10" saw? The brake rotors on that
car are IIRC 11.5 inch diameter and the whole brake assembly fits
inside a 15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

You want to put that goober under a car where it has to contend with dirt,
water, oil, ice, salt, road-kill entrails, and have it work reliably???

Common sense says it won't work and can't be made to work. Don't believe
your lyin' eyes.

It's the clearance issues around a tilting arbour more than the dirt
and sawdust. A purpose built caliper could be used on the opposite end
of the motor on a direct drive saw - but a drum would be just as
effective and smaller for the same stopping power. You don't need the
fade resistance of a disk brake for the application, nor the thermal
mass of a Lincoln car caliper.

On 10/13/2010 02:32 PM, J. Clarke wrote:
In ,
says...

On 10/13/10 9:43 AM, J. Clarke wrote:
In , says...

J. Clarke wrote:
In , says...

J. Clarke wrote:
In ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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


When it snapped (seriously)? I'm not an engineer, so I don't know for
sure. I just wouldn't be surprised. Maybe someone else can opine.

Why would something that can stop a 4000 pound car "snap" when called on
to stop a 3 pound saw blade?

"Pyrotechnics" rather than a master cylinder with brake fluid?

To stop the saw in a fraction of a revolution, you need rapid
application. A pyro will build pressure rapidly.

I didn't think we were talking about an emergency stop.
AFAIK, we're discussing a convenience stop which, in my opinion, would
be satisfactorily done in a couple seconds, not milliseconds.

Well, geez, for that a bicycle brake will work fine.

Another reality check for all the people taking this thread off into the wild blue yonder is
the issue of getting the blade onto the arbor in the presence of calipers that grip either
side of the blade. My interest (and Mike's as well, I think) in using a bicycle brake was
simply a matter of "how can I retrofit my existing table saw with a simple convenience
brake?" I think the wide-opening jaws of a bicycle brake (maybe along with some kind of
front-side cable disconnect to allow the calipers to drop out of the way) would allow enough
clearance to get the blade on the arbor without too much trouble. This heavy-duty
automotive caliber Saw-Stop alternative that everybody else is talking about would also have
to provide a similar mechanism, which would of course add to the complexity.

--
So will there ever be a day, throughout the rest of my life, that I
won't encounter in the written word a case of somebody not understanding
the difference between the meanings of the words "to" and "too"?
To reply, eat the taco.
http://www.flickr.com/photos/bbqboyee/

In article ,
says...

On Wed, 13 Oct 2010 23:15:27 -0400, "J. Clarke"
wrote:

In article ,
says...

On Wed, 13 Oct 2010 18:15:40 -0400, "J. Clarke"
wrote:

In article ,
says...

On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

In article ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, Bill wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

But would also be totally impractical on a 10" saw.

Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It works reliably on a tilting Lincoln wheel in the path of rain, road
dust, and whatever else mother nature can throw at it, so why does a
nice, dry saw cabinet present such problems?

Do yourself a favor, pull a wheel off your car and _look_ at the
mechanism.

I've been doing it for over 45 years
I've also rebuilt a few tilting arbour saws - both belt drive, gear
drive, and direct drive..

And yet you see a problem.

In article ,
says...

On Wed, 13 Oct 2010 23:16:27 -0400, "J. Clarke"
wrote:

In article ,
says...

As I stated posters seem to lean towards the technology they are comfortable
with.

The mechanics would be a nightmare to me, also. To others the electronics
would be a nightmare.

Contactor and resistor?...way too complicated.

So tell us how to wire an induction motor to make the "contactor and
resistor" work.
On an induction motor the process is a bit different. Instead of a
resistor across the motor to stop it you use "DC Injection" - in other
words throw about 40 volts DC across the winding for about 2 seconds.

So now you have to add a power supply and controls.

In article ,
says...

On 10/13/2010 02:32 PM, J. Clarke wrote:
In ,
says...

On 10/13/10 9:43 AM, J. Clarke wrote:
In , says...

J. Clarke wrote:
In , says...

J. Clarke wrote:
In ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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


When it snapped (seriously)? I'm not an engineer, so I don't know for
sure. I just wouldn't be surprised. Maybe someone else can opine.

Why would something that can stop a 4000 pound car "snap" when called on
to stop a 3 pound saw blade?

"Pyrotechnics" rather than a master cylinder with brake fluid?

To stop the saw in a fraction of a revolution, you need rapid
application. A pyro will build pressure rapidly.

I didn't think we were talking about an emergency stop.
AFAIK, we're discussing a convenience stop which, in my opinion, would
be satisfactorily done in a couple seconds, not milliseconds.

Well, geez, for that a bicycle brake will work fine.

Another reality check for all the people taking this thread off into the wild blue yonder is
the issue of getting the blade onto the arbor in the presence of calipers that grip either
side of the blade. My interest (and Mike's as well, I think) in using a bicycle brake was
simply a matter of "how can I retrofit my existing table saw with a simple convenience
brake?" I think the wide-opening jaws of a bicycle brake (maybe along with some kind of
front-side cable disconnect to allow the calipers to drop out of the way) would allow enough
clearance to get the blade on the arbor without too much trouble. This heavy-duty
automotive caliber Saw-Stop alternative that everybody else is talking about would also have
to provide a similar mechanism, which would of course add to the complexity.

C-clamp.

wrote:
On Wed, 13 Oct 2010 22:52:34 -0400, "Josepi"
wrote:

As I stated posters seem to lean towards the technology they are
comfortable with.

The mechanics would be a nightmare to me, also. To others the
electronics would be a nightmare.

Contactor and resistor?...way too complicated.


wrote in message
...
You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It's BECAUSE I was a mechanic for several decades that I would NOT use
a brake caliper for the application.

As a guy who has done all of his own vehicle maintenance for 40 years now, I
have to ask what you observed in your experiences, that causes you to make
this statement? I don't know if the brake caliper idea is the most elegant
solution, but I sure can't see anything in what you are saying that would
suggest it is not a workable solution.

--

-Mike-

Steve Turner wrote:


Another reality check for all the people taking this thread off into
the wild blue yonder is the issue of getting the blade onto the arbor
in the presence of calipers that grip either side of the blade. My
interest (and Mike's as well, I think) in using a bicycle brake was
simply a matter of "how can I retrofit my existing table saw with a
simple convenience brake?" I think the wide-opening jaws of a
bicycle brake (maybe along with some kind of front-side cable
disconnect to allow the calipers to drop out of the way) would allow
enough clearance to get the blade on the arbor without too much
trouble. This heavy-duty automotive caliber Saw-Stop alternative
that everybody else is talking about would also have to provide a
similar mechanism, which would of course add to the complexity.

It would be quite easy to mount the caliper on a pivoting mount that would
allow it to swing out of the way for changing blades.

--

-Mike-

On 10/14/2010 7:52 AM, Mike Marlow wrote:
Steve Turner wrote:


Another reality check for all the people taking this thread off into
the wild blue yonder is the issue of getting the blade onto the arbor
in the presence of calipers that grip either side of the blade. My
interest (and Mike's as well, I think) in using a bicycle brake was
simply a matter of "how can I retrofit my existing table saw with a
simple convenience brake?" I think the wide-opening jaws of a
bicycle brake (maybe along with some kind of front-side cable
disconnect to allow the calipers to drop out of the way) would allow
enough clearance to get the blade on the arbor without too much
trouble. This heavy-duty automotive caliber Saw-Stop alternative
that everybody else is talking about would also have to provide a
similar mechanism, which would of course add to the complexity.

It would be quite easy to mount the caliper on a pivoting mount that would
allow it to swing out of the way for changing blades.

Yes, probably; most automobiles with disc brakes that I've worked on use a
similar pivot mechanism. But then there's the matter of pivoting the caliper
from above the table. I can't imagine there'd be enough room through the
insert opening on the table-top to actuate such a mechanism, so you'd probably
need some kind of easy-access lever or opening in the cabinet that would allow
you to get to it.

--
"Our beer goes through thousands of quality Czechs every day."
(From a Shiner Bock billboard I saw in Austin some years ago)
To reply, eat the taco.
http://www.flickr.com/photos/bbqboyee/

On Thu, 14 Oct 2010 08:50:21 -0400, "Mike Marlow"
wrote:

wrote:
On Wed, 13 Oct 2010 22:52:34 -0400, "Josepi"
wrote:

As I stated posters seem to lean towards the technology they are
comfortable with.

The mechanics would be a nightmare to me, also. To others the
electronics would be a nightmare.

Contactor and resistor?...way too complicated.


wrote in message
...
You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It's BECAUSE I was a mechanic for several decades that I would NOT use
a brake caliper for the application.

As a guy who has done all of his own vehicle maintenance for 40 years now, I
have to ask what you observed in your experiences, that causes you to make
this statement? I don't know if the brake caliper idea is the most elegant
solution, but I sure can't see anything in what you are saying that would
suggest it is not a workable solution.

Suitable placement of an air nozzle tube to clear the caliper frame
every hour or so would go far into making this device work for more
than an hour. You'd have to keep the sawdust from piercing the seals
and/or building up on the frame

--
Do not taunt Happy Fun Ball!

Larry Jaques wrote:
On Thu, 14 Oct 2010 08:50:21 -0400, "Mike Marlow"
wrote:


As a guy who has done all of his own vehicle maintenance for 40
years now, I have to ask what you observed in your experiences, that
causes you to make this statement? I don't know if the brake
caliper idea is the most elegant solution, but I sure can't see
anything in what you are saying that would suggest it is not a
workable solution.

Suitable placement of an air nozzle tube to clear the caliper frame
every hour or so would go far into making this device work for more
than an hour. You'd have to keep the sawdust from piercing the seals
and/or building up on the frame

Not at all Larry, if you consider what a normal brake caliper in an
automobile is subject to. In comparison, the environment inside a table saw
would be a walk in the part of a caliper.

--

-Mike-

On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a convenience
slow/stop.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

On 10/14/2010 11:15 AM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one pad on
the arbor side of the blade would be sufficient for a convenience slow/stop.

That very well could be true, and you could also use such a brake with dado
blades of any thickness... Interesting observation there Mike; I'm gonna have
to go do some peeking inside my Unisaw to see what the possibilities are. :-)

--
See Nad. See Nad go. Go Nad!
To reply, eat the taco.
http://www.flickr.com/photos/bbqboyee/

On 10/14/10 11:17 AM, Bill wrote:
On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

How? Really. :-)


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On 10/14/10 11:27 AM, Steve Turner wrote:
On 10/14/2010 11:15 AM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on
the arbor side of the blade would be sufficient for a convenience
slow/stop.

That very well could be true, and you could also use such a brake with
dado blades of any thickness... Interesting observation there Mike; I'm
gonna have to go do some peeking inside my Unisaw to see what the
possibilities are. :-)


Good. It's about time that happens to someone *else.*
Let me know what you come up with so I can take credit for it. :-)


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On 10/14/2010 11:47 AM, -MIKE- wrote:
On 10/14/10 11:27 AM, Steve Turner wrote:
On 10/14/2010 11:15 AM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on
the arbor side of the blade would be sufficient for a convenience
slow/stop.

That very well could be true, and you could also use such a brake with
dado blades of any thickness... Interesting observation there Mike; I'm
gonna have to go do some peeking inside my Unisaw to see what the
possibilities are. :-)


Good. It's about time that happens to someone *else.*
Let me know what you come up with so I can take credit for it. :-)

Well, peek I did, but it seems the opportunities for mounting such a device, on
the Unisaw at least, are virtually nil. There are just too many clearance
problems to overcome. However, it does seem possible that I could mount a thin
disc to the motor pulley (one that's a couple of inches larger in diameter) and
apply caliper pressure to that instead. The calipers would have to be mounted
to a bracket that attaches to the motor housing, but that shouldn't be too hard
to accomplish.

--
Free bad advice available here.
To reply, eat the taco.
http://www.flickr.com/photos/bbqboyee/

On 10/14/2010 12:44 PM, -MIKE- wrote:
On 10/14/10 11:17 AM, Bill wrote:
On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into
the
wild blue yonder is the issue of getting the blade onto the arbor in
the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get
the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

How? Really. :-)


I'll defer to your wisdom and experience which is surely more vast than
mine. My limited experience and intuition tells me "something is wrong
in that picture"... : )

Bill

"HeyBub" writes:
wrote:
This is all assuming a clean blade for the proper high co-efficient
of friction.
Dust od sap build-up on the blade can change that very quickly.

Consider what a disk brake caliper has to overcome: dirt, water, oil,
pigeons. It still does a pretty good job.


On the other hand, disc brakes are designed so they don't lock up,
this includes the materials used as well plus the modern ABS electronics.

scott

"J. Clarke" writes:
In article ,
says...

On Wed, 13 Oct 2010 18:15:40 -0400, "J. Clarke"
wrote:

In article ,
says...

On Tue, 12 Oct 2010 22:25:50 -0400, "J. Clarke"
wrote:

In article ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, Bill wrote:

J. Clarke wrote:
In , says...

I would think that an emergency stop mechanism would be a whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to stop the blade
in a few teeth passings. For everyday usage a couple dozen blade rotations
would be OK too. These two situations would require different tactics.

A dynamic electronic brake could vary the intensity for the two different
scenarios and we could add the caliper to the emerg stop. A caliper probably
wouldn't last long in everyday usage and would need to be adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a car
with 10" rotors lasts 40,000 miles or so, and they're getting a Hell of
a lot more of a workout that they would stopping a little bitty saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a speeding
bullet on a dime--it challenges my imagination. Probably not quite as
difficult as stopping a lightning bolt, but I wouldn't want to try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad" and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

But would also be totally impractical on a 10" saw.

Why would it be "impractical on a 10" saw? The brake rotors on that car
are IIRC 11.5 inch diameter and the whole brake assembly fits inside a
15" wheel.

You want to put that monstrosity on a tilting arbour saw, mounted
under the saw table and in the path of the saw-dust and have it work
reliably???
Not going to happen - guaranteed.

It works reliably on a tilting Lincoln wheel in the path of rain, road
dust, and whatever else mother nature can throw at it, so why does a
nice, dry saw cabinet present such problems?

Do yourself a favor, pull a wheel off your car and _look_ at the
mechanism.


A car wheel spinning at 5000RPM's isn't stopped within a single rotation
by a caliper disc brake. Why would you expect a saw blade to be?

A car brake is designed to avoid locking up, yet that's exactly the
behavior you would want with a sawblade, and you'd want it to lock in
much less than a single revolution.

On Oct 13, 12:49*pm, -MIKE- wrote:
On 10/13/10 11:30 AM, Bill wrote:





-MIKE- wrote:
On 10/13/10 9:43 AM, J. Clarke wrote:
In , says...

J. Clarke wrote:
In , says...

J. Clarke wrote:
In ,
says...

On Mon, 11 Oct 2010 19:59:30 -0400, wrote:

J. Clarke wrote:
In ,
says...

I would think that an emergency stop mechanism would be a
whole different
magnitude than a scheduled, everyday, stop.

For a finger saver an emergency stop mechanism would have to
stop the blade
in a few teeth passings. For everyday usage a couple dozen
blade rotations
would be OK too. These two situations would require different
tactics.

A dynamic electronic brake could vary the intensity for the
two different
scenarios and we could add the caliper to the emerg stop. A
caliper probably
wouldn't last long in everyday usage and would need to be
adjusted and/or
replaced frequently.

So how much power do you have to put into that electronic brake
to stop
the blade as fast as Sawstop's physical block?

And why would a caliper not last long? A set of brake pads on a
car
with 10" rotors lasts 40,000 miles or so, and they're getting a
Hell of
a lot more of a workout that they would stopping a little bitty
saw
blade that masses less than 1/1000 as much.

The physics on that seem interesting. A little like stopping a
speeding
bullet on a dime--it challenges my imagination. Probably not
quite as
difficult as stopping a lightning bolt, but I wouldn't want to
try that
either.

Bill
No way a caliper could stop the blade in even 4X the time the
saw-stop does. And keeping dust out of the gap between tha "pad"
and
the blade would be quite problematic - with dust decreasing the
stopping efficiency by a very large margin.

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

When it snapped (seriously)? I'm not an engineer, so I don't know for
sure. I just wouldn't be surprised. Maybe someone else can opine.

Why would something that can stop a 4000 pound car "snap" when
called on
to stop a 3 pound saw blade?

"Pyrotechnics" rather than a master cylinder with brake fluid?

To stop the saw in a fraction of a revolution, you need rapid
application. A pyro will build pressure rapidly.

I didn't think we were talking about an emergency stop.
AFAIK, we're discussing a convenience stop which, in my opinion, would
be satisfactorily done in a couple seconds, not milliseconds.

I thought we were discussing a stop on the same order as SawStop.
I didn't read every post in the thread.

Bill

Someone brought SawStop into the discussion, which took things on a
tangent.
We started out discussing the OP's link to a set of motor reversing
instructions as a way to slow down the blade for convenience. Then I
proposed the use of a bicycle brake... and things went from there.

--

* -MIKE-

* "Playing is not something I do at night, it's my function in life"
* * *--Elvin Jones *(1927-2004)
* --
*http://mikedrums.com
*
* ---remove "DOT" ^^^^ to reply

A thread getting knocked off the rails here in the Wreck.... imagine
my surprise...LOL

On 10/14/10 11:58 AM, Bill wrote:
On 10/14/2010 12:44 PM, -MIKE- wrote:
On 10/14/10 11:17 AM, Bill wrote:
On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into
the
wild blue yonder is the issue of getting the blade onto the arbor in
the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow
the
calipers to drop out of the way) would allow enough clearance to get
the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a
convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

How? Really. :-)


I'll defer to your wisdom and experience which is surely more vast than
mine. My limited experience and intuition tells me "something is wrong
in that picture"... : )

Bill


And here I thought usenet for was for sharing ideas and learning from
one another.
How silly of me.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On Oct 14, 12:47*pm, -MIKE- wrote:
On 10/14/10 11:27 AM, Steve Turner wrote:





On 10/14/2010 11:15 AM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into the
wild blue yonder is the issue of getting the blade onto the arbor in the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow the
calipers to drop out of the way) would allow enough clearance to get the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on
the arbor side of the blade would be sufficient for a convenience
slow/stop.

That very well could be true, and you could also use such a brake with
dado blades of any thickness... Interesting observation there Mike; I'm
gonna have to go do some peeking inside my Unisaw to see what the
possibilities are. :-)

Good. *It's about time that happens to someone *else.*
Let me know what you come up with so I can take credit for it. * * :-)

--

* -MIKE-

* "Playing is not something I do at night, it's my function in life"
* * *--Elvin Jones *(1927-2004)
* --
*http://mikedrums.com
*
* ---remove "DOT" ^^^^ to reply

Oh the mootness. (NOT aimed at anybody in particular)

Any disc or drum of any size will interfere with the raising of the
blade to the point that the disk brake hits the bottom of the table
somewhere.

I propose an air bag. Electronically triggered, it throws you
backwards across the shop and away from the table saw. Punches you
right in the chest with the option for a double bag for some people
here in which case the second bag knocks some sense in them. We can
glue on a boxing glove for that operation...just a 4 oz. one; you want
it to hurt a little.
One can mount the boxing glove on an expanding multi-pivot articulated
parallelogram.
What a stellar idea.
I'm talking to investors now.
They want to call the company ACME.

On 10/14/10 12:58 PM, Robatoy wrote:
Any disc or drum of any size will interfere with the raising of the
blade to the point that the disk brake hits the bottom of the table
somewhere.

I propose an air bag. Electronically triggered, it throws you
backwards across the shop and away from the table saw. Punches you
right in the chest with the option for a double bag for some people
here in which case the second bag knocks some sense in them. We can
glue on a boxing glove for that operation...just a 4 oz. one; you want
it to hurt a little.
One can mount the boxing glove on an expanding multi-pivot articulated
parallelogram.
What a stellar idea.
I'm talking to investors now.
They want to call the company ACME.

Beautiful. Wile E. fricken beautiful.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On 10/14/2010 1:47 PM, -MIKE- wrote:
On 10/14/10 11:58 AM, Bill wrote:
On 10/14/2010 12:44 PM, -MIKE- wrote:
On 10/14/10 11:17 AM, Bill wrote:
On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into
the
wild blue yonder is the issue of getting the blade onto the arbor in
the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow
the
calipers to drop out of the way) would allow enough clearance to get
the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a
convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

How? Really. :-)


I'll defer to your wisdom and experience which is surely more vast than
mine. My limited experience and intuition tells me "something is wrong
in that picture"... : )

Bill


And here I thought usenet for was for sharing ideas and learning from
one another.
How silly of me.

The problem with me sharing something about this is that someone might
(conceivably, if they had been drinking, perhaps...) think I know what
I'm talking about. I was just thinking about all of the bicycles I've
seen that had a brake pad on just one side...

It couldn't be any good for the bearings (on the motor on the TS), huh?

Bill

On 10/14/2010 1:47 PM, -MIKE- wrote:
On 10/14/10 11:58 AM, Bill wrote:
On 10/14/2010 12:44 PM, -MIKE- wrote:
On 10/14/10 11:17 AM, Bill wrote:
On 10/14/2010 12:15 PM, -MIKE- wrote:
On 10/14/10 6:39 AM, Steve Turner wrote:
Another reality check for all the people taking this thread off into
the
wild blue yonder is the issue of getting the blade onto the arbor in
the
presence of calipers that grip either side of the blade. My interest
(and Mike's as well, I think) in using a bicycle brake was simply a
matter of "how can I retrofit my existing table saw with a simple
convenience brake?" I think the wide-opening jaws of a bicycle brake
(maybe along with some kind of front-side cable disconnect to allow
the
calipers to drop out of the way) would allow enough clearance to get
the
blade on the arbor without too much trouble.

Heck, I think if it was mounted closer to the arbor than the edge, one
pad on the arbor side of the blade would be sufficient for a
convenience
slow/stop.

Maybe so, but that sounds like asking for trouble!

Bill

How? Really. :-)


I'll defer to your wisdom and experience which is surely more vast than
mine. My limited experience and intuition tells me "something is wrong
in that picture"... : )

Bill


And here I thought usenet for was for sharing ideas and learning from
one another.
How silly of me.


I read this on the Internet:
... avoid unnecessary stress on the motor or arbor bearings.

Bill