Dc question 6" pipe seprate to two 4" pipes?

[doug barr]

If I run 6" pipe towards my table saw and then "Y" off to two 4" pipes, one for the saw body and one for the blade guard, have I overcome the restriction and will I get good air flow speed and dust collection? Both of these will be open at the same time. I have done the calculations and the area of two 4" pipes is still smaller than the one 6". Your thoughts? Thanks Doug

[glenn bradley]

True the area is smaller and a 5" and 4" may be a better choice. That being said I run from a 6" to a 4" for below and a 3" for my over-arm. Not ideal but very functional with my 2HP cyclone.

[Jim O'Dell]

I run a 6" directly into the saw cabinet, and a 4" off another 6" line overhead for the O/H pickup. And I run both at the same time. Haven't seen any problems. Jim.

[Chris Friesen]

The classic table saw collection is to split the 6" into 5" for the cabinet and 3" for the blade guard. That said, 4"/4" should work just fine. Just remember that you need equivalently-sized openings for air to flow into the guard/cabinet as the size of the duct that is sucking from it, otherwise it's not operating at full efficiency.

[Mitchell Andrus]

Just remember that you need equivalently-sized openings for air to flow into the guard/cabinet

At least equivalent, should be larger. Once I opened my TS's motor access door a crack, the air flow improved tremendously and nothing collects in the bottom of the cabinet anymore. Airflow is the second half of the design, and the most often/easiest to overlook... not just on TS. My jointer has very bad flow so I opened a few small holes in the pipe just off the cabinet - swoosh!

With no air getting into and through the machine, it doesn't matter what size the pipe is.
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[Jim O'Dell]

That is very true Mitchell. Most people want to plug up all the holes on their equipment. I think the best thing is to open holes in strategic places to put the air flow where you want it. On a TS or a BS, try to get the air flow right across the blade. Easier said than done, though. Jim.

[Mitchell Andrus]

Jim O'Dell... You have any idea why your name shows as O\'Dell in the tree list? Kinda odd.
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[David Cefai]

You have any idea why your name shows as O\'Dell in the tree list? Kinda odd.

The backslash is an "escape character". It tells the computer that the apostrophe does not have a special function. Otherwise it will be interpreted as he start of a quoted string and the poor little mite will frantically search for another one to close the string. Which can have some truly magnificent (=catastrophic) results.

[Dave MacArthur]

Hi,
Good thread on this same topic about 2 weeks ago, read my two posts for all the calculations on what size to hookup from a 6" line to 2 pickups. I tried to write a "DC theory wrap-up" post, so you may get more out of it than a quick answer.

http://www.sawmillcreek.org/showthre...ust+collection

Dave

[ronald brand]

These threads are very informative but always refer to min cfm or exact sizing. In a similar situation (eg,miter saw) any harm in 6' pipe split at the machine into 2 6" branches? Can you have too big of a port at the pick up?

[Anthony Whitesell]

Yes. A 6" duct split into two 6" ports will only give you 1/2 the CFM at each and effectively reduce your pickup by a factor of 4. I tried it with 4" when I was misinformed. I dropped to a 3" and a 3 1/2" (I placed a wooden donut in the dust hood) and the collection rate went up incrediably.