# GMC Dust Extractor/Collectorx



## NewBi (Mar 23, 2017)

Greeting,

I just got a GMC Dust Extractor/Collector 3/4 HP (RDC100M) Dust Collector with the Dust Deputy and a Wien Filter. My question is: Why does my shop vac have way more suction than the GMC Dust Collector?

I have attached two pictures of the two setups.

Thanks,
Gary


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## _Ogre (Feb 1, 2013)

your choking the dust collector too much. coming out of the fan unit into 2.5'' vacuum hose is not ideal and that dust deputy is for a shop vac with 2.5'' hose. shop vac has low cfm but higher suction by design of the impeller. the fan unit has high cfm also by design of the impeller.
if your gonna use a 5 gal bucket with dust deputy on top you're probably better off with a shop vac. for the fan unit use 4 inch pvc and a thien baffle with 4 inch connections


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## NewBi (Mar 23, 2017)

_Ogre said:


> your choking the dust collector too much. coming out of the fan unit into 2.5'' vacuum hose is not ideal and that dust deputy is for a shop vac with 2.5'' hose. shop vac has low cfm but higher suction by design of the impeller. the fan unit has high cfm also by design of the impeller.
> if your gonna use a 5 gal bucket with dust deputy on top you're probably better off with a shop vac. for the fan unit use 4 inch pvc and a thien baffle with 4 inch connections


Thank you for the reply.

All of my tools are 2.5 hose connection. Am I just out of luck?

Thanks,

Gary


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## epicfail48 (Mar 27, 2014)

Suction isnt the same as air movement. A shopvac will create loads of suction but move comparatively little air, think something like a pressure washer. Tons of force behind very little stuff. 

In contract, a dust collector is meant to move a lot of air, with suction power being secondary. Sticking with the water analogy, its more of a garden hose, moves a lot of stuff, but doesnt push very hard. 

For general cleaning, higher suction is great as itll allow the vacuum to move heavier bits of junk and the air stream to reach a bit further. A dust collector doesnt need to pick up screws though, wood dust is light and its a lot more important to be moving a larger volume of air through the filter to catch as much dust as possible. For your setup, the best bet would be a 4 inch hose running from the collector to the tool with a reduced right at the tool. You want to choke down as close to the dust source as possible. The dust collector wont be running at peak efficiency this way, but itll still likely work better than the vacuum


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## NewBi (Mar 23, 2017)

epicfail48 said:


> Suction isnt the same as air movement. A shopvac will create loads of suction but move comparatively little air, think something like a pressure washer. Tons of force behind very little stuff.
> 
> In contract, a dust collector is meant to move a lot of air, with suction power being secondary. Sticking with the water analogy, its more of a garden hose, moves a lot of stuff, but doesnt push very hard.
> 
> For general cleaning, higher suction is great as itll allow the vacuum to move heavier bits of junk and the air stream to reach a bit further. A dust collector doesnt need to pick up screws though, wood dust is light and its a lot more important to be moving a larger volume of air through the filter to catch as much dust as possible. For your setup, the best bet would be a 4 inch hose running from the collector to the tool with a reduced right at the tool. You want to choke down as close to the dust source as possible. The dust collector wont be running at peak efficiency this way, but itll still likely work better than the vacuum


Thank you sir for the explanation and info. I will try to get some 4" hose and reduce at the tool and see how that works out.

Thanks again,

Gary


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## _Ogre (Feb 1, 2013)

you still need to increase the air flow in the dust deputy and also in the lines. a gate that you can adjust past your tool hook up will do this


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