Dust collector setup

nhgal | Posted in Power Tools and Machinery on April 30, 2005 02:21am

After many years of eating, breathing, wiping from eyes, and all other adversities of dealing with SAWDUST, I have broke down and bought a Dust Collector! Now I can remove the giant fan from the back window and keep the heat inside during these frigid New Hampshire winters!! My shop is on the top floor of a two-story barn, (both floors at ground level because of a small hill) so I can run collector piping under the shop floor to various stationary machines, but my need for pipe is great, since my shop is quite large. Is there anything really wrong with using thinwall 4″ rigid plastic pipe of the inexpensive Home Depot variety instead of the expensive dust-collector stuff sold elsewhere by the dust-collector accessory market?

Replies

mikegagne | Apr 30, 2005 08:49am | #1
the wall thickness is not as critical as the static build up from the plastic with shavings and particles moving through it. I'd be surprised if your supplier didnt reccomend metal pipe. And make sure you have a size drop in the pipe as you make connections progressively away from the collector or be able to connect that hose to each machine as you use them.
arw01 | Apr 30, 2005 03:22pm | #2
A friend recently replaced all his PVC with metal in a much smaller shop then yours. He felt the suction boose was 3-4 times what plastic pipe had been giving him.

Depending on CFM, you could get away with a heavy HVAC duct, check what a local heating/cooling contractor would make you up some pipe for.

Alan
DougF | Apr 30, 2005 04:53pm | #3
Bobby,

Thin-wall will work very well and, contrary to urban myth, you don't need to ground to dissipate static discharge. Thin-wall PVC is available in diameters up to 12" from irrigation supply houses and at very reasonable prices. The thing you do not want to do is have runs using 4" pipe or you will dramatically reduce the efficiency of your DC. Typically, the main lines are sized to the CFM capacity of your DC and then the lateral lines reduce in diameter as fewer machines are on-line. It is best to take the 5" line directly to the 4" port at the machine and couple with a reducer. If you have to use 4" then try to keep it as short as possible. My 2 hp cyclone system starts out with 7", reduces to 6" and then 5" for everything else. I have a total of 50' of main lines. If you have long runs then you may want to consider placing the DC in the center of the equipment and radiating the lines outward so that no one line is very long. The smaller you make the pipe the more static pressure is created which, in turn, lowers the overall CFM. Couple this with long runs and unless your system is really big, I think you will be very disappointed with the results.

Doug
forestgirl | Apr 30, 2005 05:10pm | #4
Bobby, welcome to the New DC Owners' Club, I just got a Jet canister collector and am facing the same challenges re: set-up. Two resources to take a look at:
- Bill Pentz's DC web site, which is mentioned in just about every DC thread that comes up. Here is the link to the ducting section. He recommends PVC 2729 Sewer and Drain (S&D) Pipe for hobby use, saying that it's less expensive than Schedule 40 PVC and that it's "much stronger than metal pipe, doesn't leak like HVAC pipe, and has a much lower coefficient of friction than even spiral metal ductwork."
- "Grounding PVC and Other Dust Collecting Myths" at Wood Central. Whether or not you come to agree with Rod Cole about the possibility of static discharge and dust explosion, it's worth knowing there are two opinions on the matter and taking a look at the other side.
Let us know how it goes!

forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Another proud member of the "I Rocked With ToolDoc Club" .... :>)

Edited 4/30/2005 10:11 am ET by forestgirl