Thread: 3HP Twin Bag DC with only a single bag/filter?

Putting a non purposed made cyclone unto a DC will drop the air flow flow between 20 and 40%. Then you want to run only one filter and one collection bag which will drop the flow even further. Just remember the fine dust collection is all about maximising air flow.

If you are determined to run cyclone then as you say you don't need the collection bags you so could retain the benefit of the two filter flow by replacing one of the lower collection bag with the other filter.
You will still need to clean filters regularly as the cyclone won't separate out the really fine dust.

Originally Posted by 79njbell

... is it possible to run a 3HP Twin Bag DC with just one of the bags and filter?
...is there any air flow impacts/reduced suction?...

It's less about the filter than it is the collector ring that holds the filter and bag. The collector ring is actually a simple centrifugal separator. Think of it as a very rudimentary cyclone. As such it has resistance to flow. For such a seemingly simple device the resistance is surprisingly high. The typical 0.5 m diameter separator has a flow resistance similar to 40 m of 150 mm pipe.

When two of them are used in parallel the flow to each is cut in half and, since pressure loss varies with the square of flow rate, the pressure loss is cut by four. So, two rings is equivalent to about 10 m of 150 mm pipe. Or, removing one of the two on your system is equivalent to adding about 30 m of pipe.

A cyclone the size of a Super Dust Deputy XL is probably close to 10 m of 150 mm pipe. So your proposed modification would have about the same performance loss as adding 40 m of 150 mm pipe to the unmodified system.

There's really no need for two separators in a DC. Keeping the old one as a filter holder is a waste of static pressure. The best way to add a cyclone is to get rid of the original separator(s) and go directly into the filter. e.g.,

SDD no Ring.jpg