# My attempt at dust Collection



## hittlew (Dec 9, 2021)

When I was laying out my shop build I put pvc pipe under the slab and stubbed out at each machine location. The main line "dashed in photo" is 6" and all other lines are 4". I thought this would be a great idea but now not so sure. After reading posts on here I wish I would have ran 8" and 6". I'm still just using a 1 1/2 hp delta bag D/C moved to each machine that is in use. Waiting on purchasing a 5hp D/C or building the Bill Pentz design before attempting to use the inground system. Do you guys see any issues with my design other than the problem of clearing a plug, that could be a real pain? I like the idea of not having pipes to negotiate around but may have overlooked some other problems.


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## DrRobert (Apr 27, 2015)

I think you’ll be fine, running 4” ducts like a lot of people would have been a huge mistake.

Which DC are you getting?


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## woodnthings (Jan 24, 2009)

hittlew said:


> When I was laying out my shop build I put pvc pipe under the slab and stubbed out at each machine location. The main line "dashed in photo" is 6" and all other lines are 4". I thought this would be a great idea but now not so sure. After reading posts on here I wish I would have ran 8" and 6". I'm still just using a 1 1/2 hp delta bag D/C moved to each machine that is in use. Waiting on purchasing a 5hp D/C or building the Bill Pentz design before attempting to use the inground system. Do you guys see any issues with my design other than the problem of clearing a plug, that could be a real pain? I like the idea of not having pipes to negotiate around but may have overlooked some other problems.
> View attachment 433600


Dr Robert exhausts his out side with a great improvment in performance. I would do the same if possible. 
He and I both have a Jet 1100 at 1.5 HP, if I recall. I use a cannister filter, his goes directly outside.
Eliminating the filters reduces the static friction, greatly so your 6" ducts would be fine.
To properly evacuate an 8" duct you would need roughly a 5 HP blower.
If you can't exhaust outside, I would suggest at least a 3 HP blower.
That Bill Pentz site is a wealth of info, but it can confusing if not overwhelming!
Go to the air flow and ducting section, ducting diameter chart, and see what he recommends.





Dust Collection Research - Ducting


This site helps small shop workers understand the risks from fine dust exposure and how to effectively protect themselves and their families from airborne dust hazards. Fine dust is so extensively studied that researchers call it PM short for particle material. A Google search on PM Health Risks...



billpentz.com


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## hittlew (Dec 9, 2021)

DrRobert said:


> I think you’ll be fine, running 4” ducts like a lot of people would have been a huge mistake.
> 
> Which DC are you getting?


I'm not sure yet, most of my equip. is grizzly and for the price I think they are exceptional. So I will probably go with them or build the Bill Pence designed cyclone and find a blower to mount on it. I have a good 3hp motor but if buying new I would go with a 5hp DC. I will exhaust outside but would still like the fine dust extraction that Pence talks about with his design. My shop is below the house so quite sure the wife would not appreciate me blowing dust everywhere. Do you or anyone on here have any experience with grizzly G0442 5hp cyclone DC. Do these modern designs copy Pence's and do a good job with fine dust?


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## hittlew (Dec 9, 2021)

woodnthings said:


> Dr Robert exhausts his out side with a great improvment in performance. I would do the same if possible.
> He and I both have a Jet 1100 at 1.5 HP, if I recall. I use a cannister filter, his goes directly outside.
> Eliminating the filters reduces the static friction, greatly so your 6" ducts would be fine.
> To properly evacuate an 8" duct you would need roughly a 5 HP blower.
> ...


Thanks I just went to his site, I was a little surprised to see that he recommended for the small shop to use all the same size duct. Well to late for me since my duct is below the slab, perfect example of thinking you know what your doing so not researching sufficiently. I was going by our ducts in the mill but of course they were using 150hp blowers. What he said makes sense now, the lower air flow from the 4" drops will cause the dust to lay down in the 6" horizontal runs. Maybe a 5hp blower would keep my airflow up and what about opening up an additional blast gate on the longest run?


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## woodnthings (Jan 24, 2009)

Yes, that was my thinking. I am certainly no dust collection "expert", but I read a lot of Pentz's writing and he's a thorough researcher and experimenter.
If you look at a lot of Harbor Freight modifications on You Tube, one of the first things most folks do it install a larger impeller off a Rikon DC.
Air speed velocity, and air flow in CFMs are the main indices of measurement in addition to static pressure. Must often off the shelf DCs like the Jets provide only a HP and a CFM rating, with an occasional static pressure reading. But that's often not really enough information to properly size a blower for your system. If you throw in 10 or 20 feet of flex hose you'll have much different results. Blast gates that don't open fully aren't a good idea and lots of folks end of modifying theirs or making their own.
It's a complex task to get it all working correctly and typically requires some experimentation to get the best results.
Don't fret over what's already been done, just figure out what you can do to improve it. If that means a 5 HP blower then do it.
They aren't terribly expensive:








5 hp HP High Pressure Blower With Motor, 13 1/2 in" Wheel Dia., 23 1/8 in"H, 230 Voltage


D/D Blower w/ Motor, 230 V




www.grainger.com





Now add a cyclone for $200.00 and you pretty much have the basics of a good system:


| eBay



Grizzly makes several 5 HP units, both standard and cyclone:





Grizzly 5 HP Cyclone Dust Collector - G0442 - Magnum Tools


Grizzly 5 HP Cyclone Dust Collector - G0442 Cyclonic action separates the heavy dust particles from the fine particles and drops them into the 55-gallon steel drum. The fine dust travels past the 16" diameter impeller and is then trapped by a cartridge filter made of spun-bond polyester that...




www.magnumtools.com


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