Dr. Deb wrote:

For those who requested a drawing/picture of my dust collector mod, it is on
"alt.binaries.pictures.woodworking." under "dust collector." It is
offered, rough as it is, in the hope that it will help.

Thanks a bunch. Won't be able to see it till after work since I can't
get any binaries here, but I'm glad I'll be able to take a look before
we leave for vacation.

For those who asked if this were not just making a single filter bag system
into a two bag system, as you will see, you were "spot on" as the Brits
say.

Cool. Just one more little detail, if you don't mind; how are you
estimating or measuring your CFM?

Dan

For those who requested a drawing/picture of my dust collector mod, it is on
"alt.binaries.pictures.woodworking." under "dust collector." It is
offered, rough as it is, in the hope that it will help.

For those who suggested upgrading to a larger unit, two things: Some of us
are restricted to 120v. Also, the cost is actually much greater, if you
have an existing dust collector.

For those who asked if this were not just making a single filter bag system
into a two bag system, as you will see, you were "spot on" as the Brits
say.


Deb

On Sat 03 Jan 2004 12:23:11a, "Dr. Deb" wrote in
:

I read an ad in one of the mags I subscribe to that said for 1 micron
filter you should figure 40-45CFM per sq ft.

Yeah, okay. That makes sense, although it seems like the force of the
impeller would be a factor. Mebbe they're figuring the "average" impeller
force, which is probably fairly constant for that type of DC.

Seems plain that adding more area for the escaping air would increase the
CFM, whatever the numbers are.

Thanks, Deb.

Dan

I am looking at buying a DC. Is there any make that is better than the other
or are they all the same? They all look much the same to me but I may be
wrong. Regards. -Guy



"Dr. Deb" wrote in message
...
I read an ad in one of the mags I subscribe to that said for 1 micron
filter
you should figure 40-45CFM per sq ft. Since the bag was 30" high and had
a
diameter of 20" simple math 20x3.1416x30=1884.96sq in, divide by 144 =
13.09 then times 45 = 589.05 CFM.

It seems about right when compared with the Jet 650CFM DC I had before
this
one.

Deb



Dan wrote:

Dr. Deb wrote:

For those who requested a drawing/picture of my dust collector mod, it
is
on
"alt.binaries.pictures.woodworking." under "dust collector." It is
offered, rough as it is, in the hope that it will help.

Thanks a bunch. Won't be able to see it till after work since I can't
get any binaries here, but I'm glad I'll be able to take a look before
we leave for vacation.

For those who asked if this were not just making a single filter bag
system into a two bag system, as you will see, you were "spot on" as
the
Brits say.

Cool. Just one more little detail, if you don't mind; how are you
estimating or measuring your CFM?

Dan

I read an ad in one of the mags I subscribe to that said for 1 micron filter
you should figure 40-45CFM per sq ft. Since the bag was 30" high and had a
diameter of 20" simple math 20x3.1416x30=1884.96sq in, divide by 144 =
13.09 then times 45 = 589.05 CFM.

It seems about right when compared with the Jet 650CFM DC I had before this
one.

Deb



Dan wrote:

Dr. Deb wrote:

For those who requested a drawing/picture of my dust collector mod, it is
on
"alt.binaries.pictures.woodworking." under "dust collector." It is
offered, rough as it is, in the hope that it will help.

Thanks a bunch. Won't be able to see it till after work since I can't
get any binaries here, but I'm glad I'll be able to take a look before
we leave for vacation.

For those who asked if this were not just making a single filter bag
system into a two bag system, as you will see, you were "spot on" as the
Brits say.

Cool. Just one more little detail, if you don't mind; how are you
estimating or measuring your CFM?

Dan

"Guy LaRochelle" wrote in message
...
I am looking at buying a DC. Is there any make that is better than the
other
or are they all the same? They all look much the same to me but I may be
wrong. Regards. -Guy




Check out Sandor N's book on dust collection from Tauton Press. (Sorry, my
copy is not at hand and I'll be darned if I can spell his last name off the
top of my head.)

Having worked with a couple different brands and installations, my dos
centavos:

-- How the bags attach / detach is important. If it's a pain in the butt to
put back on, you will get frustrated because you're wrestling with the darn
bag instead of making chips fly.

-- More CFM is better if you have things that can make lots of chips:
planer, shaper, table saw with a dado head. But, make sure the ID of your
pipes can accomdate the CFM, and that includes any flex hose from the fixed
pipe to the machine.

-- On small installtions I like the trash can cyclone. It knocks out the
big chips (thus you don't ned to empty the bag as often), is easier to
empty, and if you happen to pick some metal (such as when vacuuming the
floor) the debris probably won't go through the impeller, reducng the chance
that it will get heated up enough to start a fire. Lots of guys have burned
down their shops by having something smoldering in the DC.

What is a trash can cyclone? Regards. -Guy


-- On small installtions I like the trash can cyclone. It knocks out the
big chips (thus you don't ned to empty the bag as often), is easier to
empty, and if you happen to pick some metal (such as when vacuuming the
floor) the debris probably won't go through the impeller, reducng the
chance
that it will get heated up enough to start a fire. Lots of guys have
burned
down their shops by having something smoldering in the DC.

In article ,
"Dr. Deb" wrote:

I read an ad in one of the mags I subscribe to that said for 1 micron filter
you should figure 40-45CFM per sq ft. Since the bag was 30" high and had a
diameter of 20" simple math 20x3.1416x30=1884.96sq in, divide by 144 =
13.09 then times 45 = 589.05 CFM.

You forgot the area of the end. You've got another pi*r^2 or 3.14 *
10^2, which is about another 314 sq in. By my calculations with your
formula, that gives you about 685 CFM.

In article ,
"Tim Mueller" wrote:
-- How the bags attach / detach is important. If it's a pain in the butt to
put back on, you will get frustrated because you're wrestling with the darn
bag instead of making chips fly.

I'm with you there. I've got the Jet DC-650, and it is indeed a pain.
First it's a pain to get the cloth bag itself onto the machine, then
it's another pain to get the danged strap attached. It sure seems like
they could have designed an easier system.

A trash can "cyclone" is a piece of plastic that goes on top of a trash
can that can be hooked up to (usually) a 4" hose coming in and another
going out to a secondary "dust collector". The trouble is that there
is no bona fide industry-standard definition for a cyclone and you get
what you pay for (maybe) but rarely more.

A real cyclone separates the dust and debris from the air before
it gets to the blower, and the cyclone will remove as much as 99.98%
of ALL dust, including fine dust before it gets to the blower.

To to
http://cnets.net/~eclectic/woodworki...lone/index.cfm
for the most authoritative source of dust-collection info in the
internet. Thoroughly researched solid education. Spend some time
there before you spend any money on dust collectors.
FWIW, I manufacture cyclone kits and blower housings using the Bill
Pentz designs and ship all over North America. Details at
http://cnets.net/~eclectic/woodworki...larkesKits.cfm

CE

Guy LaRochelle wrote:

What is a trash can cyclone? Regards. -Guy

-- On small installtions I like the trash can cyclone. It knocks out the
big chips (thus you don't ned to empty the bag as often), is easier to
empty, and if you happen to pick some metal (such as when vacuuming the
floor) the debris probably won't go through the impeller, reducng the
chance
that it will get heated up enough to start a fire. Lots of guys have
burned
down their shops by having something smoldering in the DC.

For good dust retention and low static pressure through the filter,
filter air velocity should be reduced to more on the order of 5 CFM
per square foot, not 40-50. The less pressure loss through the filters,
the more air you can move.

There is a severe lack of understanding of the principles of GOOD
dust collection, or more correctly, dust ELIMINATION in the wood shop
atmosphere. I recommend investing some time at Bill Pentz's web site
at http://cnets.net/~eclectic/woodworki...lone/index.cfm . I also
produce cyclone kits and blower housings based on Bill's cyclone design.
See http://cnets.net/~eclectic/woodworki...larkesKits.cfm
for more info.

CE

"Dr. Deb" wrote:

I read an ad in one of the mags I subscribe to that said for 1 micron filter
you should figure 40-45CFM per sq ft. Since the bag was 30" high and had a
diameter of 20" simple math 20x3.1416x30=1884.96sq in, divide by 144 =
13.09 then times 45 = 589.05 CFM.

It seems about right when compared with the Jet 650CFM DC I had before this
one.

Deb

Dan wrote:

Dr. Deb wrote:

For those who requested a drawing/picture of my dust collector mod, it is
on
"alt.binaries.pictures.woodworking." under "dust collector." It is
offered, rough as it is, in the hope that it will help.

Thanks a bunch. Won't be able to see it till after work since I can't
get any binaries here, but I'm glad I'll be able to take a look before
we leave for vacation.

For those who asked if this were not just making a single filter bag
system into a two bag system, as you will see, you were "spot on" as the
Brits say.

Cool. Just one more little detail, if you don't mind; how are you
estimating or measuring your CFM?

Dan

Hi Tim, et. al.,

Tim Mueller wrote:

-- On small installtions I like the trash can cyclone. It knocks out the
big chips (thus you don't ned to empty the bag as often), is easier to
empty, and if you happen to pick some metal (such as when vacuuming the
floor) the debris probably won't go through the impeller, reducng the chance
that it will get heated up enough to start a fire. Lots of guys have burned
down their shops by having something smoldering in the DC.
Can you point to some documented cases where this has actually
happened? Most of the references I've seen appear to fall in the urban
legend category.....just wondering.

Respectfully,
J