Dust Collector Question

[Dr. Deb]

I have a HF dust collector I have highly modified. What I did was took it apart, threw away everything but the impeller and put a cyclone inline and ported the dust outside the building into a catchment area.

If I were to get another HF DC and parallel the current impeller with the one I currently have I wonder how much I would pickup in CFM? I could get a Delta, whatever, impeller and motor and improve my CFM and static pressure but about 30-35%. I wonder if the parallel arrangement would not give me on the order of 60+% increase.

I currently am running 4" PVC with 4" flex drops to about 7 blast gates. Max run is about 30 feet (including the drop). The exhaust is also 4" PVC and its run is about 30 feet, with little or no back pressure.

Thanks

Deb

[yugami]

This site may help you, it has plans and info about building your own cyclone setup. Including a link to buy a good impeller.

[Jim Behning]

How does the impeller turn?

[Greg O]

I wonder if increasing the size of your main run up to 5"would give you the extra air you are looking for. I have the HF dust collector and often run with one 4" port open, so I believe the air flow is there, but the 4" main is choking it. Greg

[rich]

Reading this thread makes me wonder: Can I leave blast gates open? I have a Delta DC with a cyclone, 20 foot run of flex 4" ( didn't think about smooth pipe when I installed this) to the saw, planer, and another 10 feet to the jointer. Opening one gate at a time seems to work pretty well, but it seems that multiple open gates would just reduce the suction at each machine. Am I missing something???

Thanks for any comments.

Regards, Rich.....

[Greg O]

Thanks for any comments.

Regards, Rich.....

Depends on the layout of the pipe, and your DC. If your DC produces more air flow than it can"suck" through one 4" blast gate opening one or two more should not matter, until the air flow through the open blast gates catch up with the air flow of the DC. Greg

[Tom Veatch]

You're not missing a thing.

A given blower will only move so much air across a given pressure differential. If you split the flow between multiple sources by opening more than one blast gate, total flow through the blower could be greater due to a lower pressure differential. But, except for exceptional situations, the flow at each source will be less than if only one gate were open.

That doesn't address the question whether or not the reduced flow at the source is still sufficient for the purpose, but in general, for hobbyist class cyclone/dust collector installations, it will not be.

Tom Veatch Wichita, KS USA