As mentioned in another message-thread, I just get a JET 1.5 HP
Canister Dust collector (rated 1100 cfm). I need help in figuring out
the best way to use it to capture dust from my table saw.
Specifically, I want to know the duct size that I should use.

I am under the impression that I should use as large a duct/hose as
possible while maintaining air speed to an acceptable level (3500 FPM
or something).

I will remove the two 4" inlets in the dust collector, and use the 6"
inlet directly (the 6" inlet is being covered by those two 4" inlets).
Starting with this 6" inlet, this means I should decide on whether I
should use 5" or 6" duct/hose.

I want to put a dust hook at the bottom of the table saw, and another
dust hook on top of the table saw. According to a dust collection
book, I should use a 6" dust port at the bottom of the table saw if I
want to do heavy duty cutting, such as doing dado. I will do dado, and
I will do dado on MDF. Seem like I should put a 6" port at the bottom.
And I am under the impression that I should use a 2" port to capture
dust on top of the table saw (right over the saw blade).

I want to increase the efficiency of dust collection by moving the
dust collector as close to the table saw as possible, and use a very
short 5-ft flex hose (that is smooth inside) to connect the dust
collector to the table saw.

The problem is that the combined size of the 6" and 2" dust ports in
the table saw will exceed the size of the 6" inlet in the dust
collector. This seems to be an imbalance. Will this cause a
bottle-neck at the 6" inlet in the dust collector?

I am also thinking of getting around this potential problem by using a
5" dust port at the bottom of the table saw instead of a 6" dust port.
But this will be against the recommendation stated in the dust
collection book. I am wondering whether I can use a 5" dust port for
dadoing if I can use a better dust hook, such as one that encloses the
saw blade instead of enclosing the bottom of the table saw.

Thanks in advance for any information on this issue.

Jay Chan

"Jay Chan" wrote in message
I am under the impression that I should use as large a duct/hose as
possible while maintaining air speed to an acceptable level (3500 FPM
or something).

Right.


I will remove the two 4" inlets in the dust collector, and use the 6"
inlet directly (the 6" inlet is being covered by those two 4" inlets).
Starting with this 6" inlet, this means I should decide on whether I
should use 5" or 6" duct/hose.

Most people that us 6" run the large line as the trunk line and branch off
to each tool with a 4". Most tools have 4" ports.



I want to put a dust hook at the bottom of the table saw, and another
dust hook on top of the table saw. According to a dust collection
book, I should use a 6" dust port at the bottom of the table saw if I
want to do heavy duty cutting, such as doing dado. I will do dado, and
I will do dado on MDF. Seem like I should put a 6" port at the bottom.
And I am under the impression that I should use a 2" port to capture
dust on top of the table saw (right over the saw blade).

With a dado you, don't need the top port as there is no dust coming up. If
you want to use the 6" on the bottom, the top can be shut off for that
operation. Of normal cutting, both should be open.

That said, I don't think you need the 6" for the saw. I have the same DC
with a 4" port on my saw. I've not cut all that much dado, but is sure
handled what I cut with ease. Just how much cutting will you do at a time
and how fast can you feed the material?


I am also thinking of getting around this potential problem by using a
5" dust port at the bottom of the table saw instead of a 6" dust port.
But this will be against the recommendation stated in the dust
collection book. I am wondering whether I can use a 5" dust port for
dadoing if I can use a better dust hook, such as one that encloses the
saw blade instead of enclosing the bottom of the table saw.

Thanks in advance for any information on this issue.

Jay Chan

I think you've been reading too much. Just how big of a shop are you going
to have? In a high production automated feed and miles of panels, the book
makes a lot of sense. If you are cutting the sides of a bookcase, the 4"
port will be plenty. I've never felt the need for more capacity even
cutting some 12/4 stock. I would like to have a hose on top though.
Ed

Most people that us 6" run the large line as the trunk line and branch off
to each tool with a 4". Most tools have 4" ports.

In my case, I don't plan to have a main trunk line. I will roll the
power tool around to position it as close to the dust collector as
possible. Sound like I don't really need a 6" port in my table saw.
Thanks for the confirmation.

None of my power tools have a dust port. This means I can decide
between 4" or 5" port without being constrainted by the existing dust
port in the power tools. I have a feeling that I will go for the 5"
fittings/hoses.

With a dado you, don't need the top port as there is no dust coming up. If
you want to use the 6" on the bottom, the top can be shut off for that
operation. Of normal cutting, both should be open.

I see. Sound like I can use a 6" hose at the bottom when I dado, and
then I can switch to use a 5" hose at the bottom and a 2" hose on top
if I am not doing dado. This is the theory. But I really doubt that I
will go this way because I don't see myself keep changing hoses from
one cut to another. I probably will stick with 5" hose at the bottom
of the table saw, and put a blast gate on the 2" port on top of the
table saw.

Thanks for pointing out that I probably don't need to open the
top-mount 2" dust port when I am dadoing. This means I may be able to
shut off the 2" dust port, and use the 5" dust port exclusively when I
am dadoing. Hopefully, this will increase the cfm in the 5" dust port
and capture all the dust from dadoing. If this doesn't work well, I
still have an option to open the top-mount dust port to see if it will
do me any good.

That said, I don't think you need the 6" for the saw. I have the same DC
with a 4" port on my saw. I've not cut all that much dado, but is sure
handled what I cut with ease. Just how much cutting will you do at a time
and how fast can you feed the material?

I tend to do everything slowly because I don't think fast. And I must
feed wood to the table saw slowly because the table saw is a bit
underpowered (110-volt) even with a new saw blade. I guess this means
I probably will not generate dust fast enough to overwhelm the 4" or
5" dust collection. Good to learn this. OK, I will drop the idea of
using 6" fittings/hoses. I will go for 5" fittings/hoses.

I think you've been reading too much. Just how big of a shop are you going
to have? In a high production automated feed and miles of panels, the book
makes a lot of sense. If you are cutting the sides of a bookcase, the 4"
port will be plenty. I've never felt the need for more capacity even
cutting some 12/4 stock. I would like to have a hose on top though.

Yes, I have been spending quite some time in reading about this
subject. Although my woodshop is very small (with only two stationary
power tools) and I don't cut wood as often as I want, I have a health
concern on dust. I used to have asthma-attack. Now I have proper
medical care and I haven't had any asthma attack for many many years.
Still, I want to play safe. This is the reason why I want to capture
as much dust as possible, and this is the reason why I want 5"
fittings/hoses instead of 4" as what you have. I just want to give
myself a bit more of margin of error.

Before someone jumps in and tells me to use a cyclone, I need to add
that I have already thought about that. But my shop doesn't have the
head-room and it also doesn't have any 220-volt power outlet to run a
2-HP blower that is needed for a cyclone. A 1.5 HP canister dust
collector is the best that I can do right now.

Thanks for sharing your experience in using the same type of dust
collector.

Jay Chan