A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

On Tue, 20 Jul 2004 14:49:19 -0700, alderotes wrote:

A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

I'd be a little concerned about incenerating the bag. But if you used a
small cyclone unit I don't see any reason why it shouldn't work.

--
The instructions said to use Windows 98 or better, so I installed RedHat.

You could also build your own, using a similar design. I would exhaust
the air to the outside, since it is hard to filter out all the fine
particles. Typically one oversizes the fan and then uses a gate or some
other way to reduce the airflow to an appropriate level. There are
plenty of handbooks that show how to design industrial exhaust systems.

I would worry about the fabric filter igniting due to hot sparks from
grinding, probably would need a high temperature non-flammable fabric or
put a metal filter in front of any fabric filter. The McMaster Carr
catalog on page 597 shows some metal filters. A cyclone filter would
probably take out the larger pieces, perhaps including the incandescent
ones.

Richard



alderotes wrote:
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

I'd be a little concerned about incenerating the bag. But if you used a
small cyclone unit I don't see any reason why it shouldn't work.

We have a small Torit dust collector on our wide belt sander and if we
use it more then a few minutes at a time the filter bags do catch on
fire. I'd suggest a dust collector with an all glass filter such as a
furnace filter. They don't have to collect exactly all the dust as
you should exhaust it outside anyway. Leigh @ MarMachine

"Richard Ferguson" wrote in message
...
You could also build your own, using a similar design. I would exhaust
the air to the outside, since it is hard to filter out all the fine
particles. Typically one oversizes the fan and then uses a gate or some
other way to reduce the airflow to an appropriate level. There are
plenty of handbooks that show how to design industrial exhaust systems.

I would worry about the fabric filter igniting due to hot sparks from
grinding, probably would need a high temperature non-flammable fabric or
put a metal filter in front of any fabric filter. The McMaster Carr
catalog on page 597 shows some metal filters. A cyclone filter would
probably take out the larger pieces, perhaps including the incandescent
ones.

Richard

I'll check out McMaster-Carr. I hadn't seen metal filters before, would be
nice if I didn't have to invent them

Thanks,

George

When you say grinder, do you mean a handheld angle grinder? If so, Bosch
and some other companies make dust collection hoods which allow you to
attach a vacuum hose to the grinder and collect the dust at the source. But
there is still the problem of the vacuum filter catching on fire.

"alderotes" wrote in message
om...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

"gglines" wrote in message
news:lVlLc.2526$BX.2374@lakeread08...

"Richard Ferguson" wrote in
message
...
You could also build your own, using a similar design. I would exhaust
the air to the outside, since it is hard to filter out all the fine
particles. Typically one oversizes the fan and then uses a gate or some
other way to reduce the airflow to an appropriate level. There are
plenty of handbooks that show how to design industrial exhaust systems.

I would worry about the fabric filter igniting due to hot sparks from
grinding, probably would need a high temperature non-flammable fabric or
put a metal filter in front of any fabric filter. The McMaster Carr
catalog on page 597 shows some metal filters. A cyclone filter would
probably take out the larger pieces, perhaps including the incandescent
ones.

Richard

I'll check out McMaster-Carr. I hadn't seen metal filters before, would
be
nice if I didn't have to invent them

Thanks,

George


George,
I had a look at the link you included.
There are a couple of thoughts apart from the obvious burning filter ones.
The downdraught table you listed is meant for finish sanding of wood. You
are suggesting a metal grinder. This sends the debris a long way whereas a
finishing sander doesn't. You will need taller side skirts and possibly a
top to the unit. You are now almost into a full cabinet build. Do you have a
blast cabinet? That might do the job.
On the subject of exhaust, if you extract your dirty air from the workshop,
it will be replaced by nice warm air from outside. Your shop will soon be as
warm as outside so why not work out there to begin with.

John

On 20 Jul 2004 19:22:03 -0700, (Leigh Knudson)
wrote:


I'd be a little concerned about incenerating the bag. But if you used a
small cyclone unit I don't see any reason why it shouldn't work.

We have a small Torit dust collector on our wide belt sander and if we
use it more then a few minutes at a time the filter bags do catch on
fire. I'd suggest a dust collector with an all glass filter such as a
furnace filter. They don't have to collect exactly all the dust as
you should exhaust it outside anyway. Leigh @ MarMachine

Distance is the solution to hot metal bits lighting the bag off -
make the downdraft welding table of all metal, and run a long
sheet-metal suction duct outside to where the dust collector fan unit
is. Any hot metal that has to travel 20' or more through the ducts
should have enough time to cool down before hitting the filter bag.

You can get sheet-metal ducting and fittings at any good home
center. And be sure to seal the joints and gaps between the ducts
with paint-on duct sealer, or you'll lose half the vacuum between the
fan and table. Duct Tape dries up and falls off, Glencoat with
embedded fabric tape for reinforcement is almost permanent.

-- Bruce --
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

Richard's leading you the right way, a metal filter has been around for
many years, most of the residential are aluminum. Think a filter for an
kitchen stove exhaust, they are usually small/thin maybe 3/8" thick
furnace a/c types are 3/4"(they say 1", but like wood it ain't or I could
call John Holmes shorty) the spray on material to make the filter more
efficient is an oil based so I don't think that would be a good idea.
also having a baffle to keep sparks/ hot metal hitting the filter material
would make it last.
tt

(alderotes) wrote in message . com...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

There's been various plans published lately for small cyclone
separators for woodworking, there's no reason these wouldn't work for
catching grinding dust. All it takes is a little tin-whacking.
There's usually a bag unit/filter on the outlet side of the separator
for catching the fines, but by that time all the heat should be gone.
The one unit I saw in a magazine sat on a 55 gal barrel for a catcher
and was about that diameter by about 7' or 8' tall when mounted. I
don't remember where they got their blower, it was more substantial
than a shop vac, though.

Stan

also having a baffle to keep sparks/ hot metal hitting the filter material
would make it last.

I recently bought a used 10" baldor grinder with a dust collector.
The dust collector sucks the sparks and dust off the grinding
wheel, through the blower and into a cloth bag. Apparently going
through metal tubes with several corners and through the blower
cools the sparks enough. The original bag was still reasonably
intact with a few tears etc.
chuck

"Stan Schaefer" wrote in message
m...
(alderotes) wrote in message
. com...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

There's been various plans published lately for small cyclone
separators for woodworking, there's no reason these wouldn't work for
catching grinding dust. All it takes is a little tin-whacking.
There's usually a bag unit/filter on the outlet side of the separator
for catching the fines, but by that time all the heat should be gone.
The one unit I saw in a magazine sat on a 55 gal barrel for a catcher
and was about that diameter by about 7' or 8' tall when mounted. I
don't remember where they got their blower, it was more substantial
than a shop vac, though.

Stan

I was looking at a larger Torit Dust collector and it had what the dealer
called a spark trap. It was a box with the air ducted past several sharp
bends with a dead end corner for the heavier particals, the one likly to be
glowing red to get caught in. I don't recall but there must have been a
cleanout door to remove this dust.
Steve Peterson

George,
I had a look at the link you included.
There are a couple of thoughts apart from the obvious burning filter ones.
The downdraught table you listed is meant for finish sanding of wood. You
are suggesting a metal grinder. This sends the debris a long way whereas a
finishing sander doesn't. You will need taller side skirts and possibly a
top to the unit. You are now almost into a full cabinet build. Do you have
a
blast cabinet? That might do the job.
On the subject of exhaust, if you extract your dirty air from the
workshop,
it will be replaced by nice warm air from outside. Your shop will soon be
as
warm as outside so why not work out there to begin with.

John

I'm thinking of a bench grinder. I don't want to exhaust to the outside of
the shop, I'm hoping to filter the air through the cabinet.

George

"Steve Peterson" 123@nospam wrote in message
...

"Stan Schaefer" wrote in message
m...
(alderotes) wrote in message
. com...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

There's been various plans published lately for small cyclone
separators for woodworking, there's no reason these wouldn't work for
catching grinding dust. All it takes is a little tin-whacking.
There's usually a bag unit/filter on the outlet side of the separator
for catching the fines, but by that time all the heat should be gone.
The one unit I saw in a magazine sat on a 55 gal barrel for a catcher
and was about that diameter by about 7' or 8' tall when mounted. I
don't remember where they got their blower, it was more substantial
than a shop vac, though.

Stan

I was looking at a larger Torit Dust collector and it had what the dealer
called a spark trap. It was a box with the air ducted past several sharp
bends with a dead end corner for the heavier particals, the one likly to
be
glowing red to get caught in. I don't recall but there must have been a
cleanout door to remove this dust.
Steve Peterson


Hmmm. . . maybe the Grizzly would work with some baffles like you describe
above a metal filter.

George

On 21 Jul 2004 20:20:20 GMT, (Charles A.
Sherwood) wrote:

also having a baffle to keep sparks/ hot metal hitting the filter material
would make it last.

I recently bought a used 10" baldor grinder with a dust collector.
The dust collector sucks the sparks and dust off the grinding
wheel, through the blower and into a cloth bag. Apparently going
through metal tubes with several corners and through the blower
cools the sparks enough. The original bag was still reasonably
intact with a few tears etc.
chuck

I have a very nice dust collector/vac head that fits on the top of a
55 gallon drum. Looks nearly new and is quite powerful.

If anyone is interested, let me know and Ill give you the details. I
also have new hoses for it.

Gunner


"This device is provided without warranty of any kind as to reliability,
accuracy, existence or otherwise or fitness for any particular purpose
and Bioalchemic Products specifically does not warrant, guarantee,
imply or make any representations as to its merchantability for any
particular purpose and furthermore shall have no liability for or
responsibility to you or any other person, entity or deity with respect
to any loss or damage whatsoever caused by this device or object or by
any attempts to destroy it by hammering it against a wall or dropping it
into a deep well or any other means whatsoever and moreover asserts
that you indicate your acceptance of this agreement or any other
agreement that may he substituted at any time by coming within
five miles of the product or observing it through large telescopes or
by any other means because you are such an easily cowed moron
who will happily accept arrogant and unilateral conditions on a piece
of highly priced garbage that you would not dream of accepting on a
bag of dog biscuits and is used solely at your own risk.'

"gglines" wrote in message
news:txHLc.4819$BX.657@lakeread08...

"Steve Peterson" 123@nospam wrote in message
...

"Stan Schaefer" wrote in message
m...
(alderotes) wrote in message
. com...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

There's been various plans published lately for small cyclone
separators for woodworking, there's no reason these wouldn't work for
catching grinding dust. All it takes is a little tin-whacking.
There's usually a bag unit/filter on the outlet side of the separator
for catching the fines, but by that time all the heat should be gone.
The one unit I saw in a magazine sat on a 55 gal barrel for a catcher
and was about that diameter by about 7' or 8' tall when mounted. I
don't remember where they got their blower, it was more substantial
than a shop vac, though.

Stan

I was looking at a larger Torit Dust collector and it had what the
dealer
called a spark trap. It was a box with the air ducted past several sharp
bends with a dead end corner for the heavier particals, the one likly to
be
glowing red to get caught in. I don't recall but there must have been a
cleanout door to remove this dust.
Steve Peterson


Hmmm. . . maybe the Grizzly would work with some baffles like you describe
above a metal filter.

George


The supplier isn't much use to you as they are in UK but one of our wood
work shops has an extraction fan adaptor that fits onto a standard dustbin
(trash can). That may work for you especially if you arrange the inlet to
point down through the top and the exhaust to draw from the top with a
baffle between them. The reduction in air speed should allow the sparks to
settle out.
Try this link to see what I mean.
http://www.axminster.co.uk/default.asp?part=DCS
Obviously use a metal bin.

John

Hand grinding with a portable grinder should be done in an isolated area.
That doesn't neccessarily mean farther away, but in a space that has
barriers to stop the airborne debris from circulating. This could be a
curtain, wall, booth or cabinet-type area.
The handheld grindr will spew crap in an infinite number of directions, so
it shouldn't be included in the area of the other machinery.

Hot sparks and grit can be directed to a pool of water (don't know what that
sweeper is named.. oh, Rainbow), and most of the crap will stick to the
water. Real air cleaners force the airstream into (under the suface) of the
water, so the debris collection is very thorough.
Hand grinding isn't always as easy to tame because of the directional
slinging of the crap. The use of curtains or something else for containment
is almost mandatory.
If a suitable blower intake is piped from the wet box (downstream from the
collection container/vessel), the debris is effectively shot into the pool
with baffles or some other means. If the vessel isn't prone to combustion,
there shouldn't be any problems when the outlet of the blower is vented
outdoors.

This is gonna suck in the winter in cold climates because this system will
evacuate the heated air from the shop. That would indicate the use of
filters for the exaust, or an air makeup supply for a system that's vented
outdoors.

WB
...............

"alderotes" wrote in message
om...
A downdraft table would be a real boon so I could use my grinder
inside the shop. I don't want the grinding dust on my machines so I
do it outdoors, but its nasty on those 112 degrees days.

The commercial ones seem to run $3,000+. Grizzly sells this model
http://www.grizzly.com/products/item...emnumber=G0534 for wood
dust. It uses a pleated fabric filter.

Probably a dumb question, but is it practical/possible to convert
something like the Grizzly model for metal dust?

Thanks,

George

On Wed, 21 Jul 2004 15:14:15 +0000, Bruce L. Bergman wrote:

Distance is the solution to hot metal bits lighting the bag off -
make the downdraft welding table of all metal, and run a long
sheet-metal suction duct outside to where the dust collector fan unit
is. Any hot metal that has to travel 20' or more through the ducts
should have enough time to cool down before hitting the filter bag.

Outstanding suggestion, and much cheaper than a cyclone.
--
The instructions said to use Windows 98 or better, so I installed RedHat.

On Tue, 20 Jul 2004 17:51:22 -0500, Jim Levie wrote:

||On Tue, 20 Jul 2004 14:49:19 -0700, alderotes wrote:
||
|| A downdraft table would be a real boon so I could use my grinder
|| inside the shop. I don't want the grinding dust on my machines so I
|| do it outdoors, but its nasty on those 112 degrees days.

Steel tubing frame, or use existing bench.
Expanded metal top, grinder mounted thereon.
Side skirts as need.
Squirrel-cage blower pulling air through the expanded metal mesh.
Baffling directing air through a water trough to catch particles and quench
sparks
Change water as needed.
Texas Parts Guy