Dust Collection - Did I miss one important thing.....

[Howard Acheson]

I can't tell from your description--are you going to vent your dust collector to the outside? If yes, then you need makeup air. If no and you plan to recirculate, no make up air is required.

[Ole Anderson]

Justin,

I saw some pictures on the ClearVue Cyclone gallery where someone built a "closet with a removeable panel" around the filters (with 4-5" of clearance for filter cleaning and access) and then used insukated HVAC ducting to route the air back. They had mounted the whole cyclone with filters in a larger closet for noise abatement. With or without the outer closet, this would be a way to recycle the filtered air back into the shop without picking up <much in> garage vapors. It concurrently removed the need to exhaust from the "garage" and provide makeup air to the shop room. Make sense?

Just one thought..

Jim

Tagging onto this idea, if you are using a cyclone, leave the blower and cyclone in the lower garage, but run an 8" duct elbowing up through the floor, a vertical piece to the top of your duct and then a 180 back down into your filter which would be located in your shop. That way you eliminate the circulation problem and gain some space in your garage with a small penalty of space allocated for just the filter in your shop. And with 8" duct on the pressure side of the blower, losses would be minimal. Taking this a step further, come up into the bottom of your filter, still in the shop, eliminate the 180 at the top, and put a short 8" sump piece (possibly a wye) with a cleanout at the bottom of the vertical run down in the garage for a cleanout when cleaning the filter.

[ian maybury]

I'd been thinking of the Cincinatti fan curves/tables Ole. Maybe the 14 1/2in dia impeller Grizzly uses has very low vanes, or presumes a high level of pressure drop or something. Looking at the CF curves again the data suggests that a 14 1/2in impeller is likely to draw way above 2HP unless its heavily restricted or neutered in some way - e.g. by a pressure drop of maybe 9in or more. I guess in the end that (whatever the impeller ) fan HP is proportional to pressure drop x airflow, and radial impeller efficiencies tend to be fairly similar. The thought is just that this installation is asking a lot from 2HP...

Even if the ducting layout can be finessed into doing better one concern is that machine hoods etc seem likely to be highly restrictive which risks swamping anything that can be done with duct sizes...

ian

[Justin Jump]

OK - so chime in here where needed......

I did not plan to vent outside, I could, but that would mean routing electrical and everything else to the other side of the garage, and lose some "parking" area. Not ideal for me, I got 2 cars, 4 ATV's and one tractor, it's pretty full.

I did not purchase the dust collector yet - this could be a good thing.

The DC would be in a seperate floor, so make up air, whether returned air from the DC, or fresh outside air is needed.

@ Ian....Not familiar with the unit you have in mind, but think Justin that you may be living a little dangerously re. low airflow by using a 2HP fan and (if I read it correctly) hoping to push air up to the second floor before distributing it around a workshop...

I don't plan on pushing air up, rather sucking air, chips and dust down. Workshop is on the top, and all the ducting will go through the floor, similar to Alan S.'s setup...

Therefore, I see the easiest solution being, keep a bag style, maybe upgrade to 3HP, and open windows for makeup air. Possibly even design/build something for the top panes of one of my windows that sort acts like a reverse louver system, letting air in when needed.

The above allows me to keep the DC below, and save floor space and noise.

Another solution I read is to upgrade to a Cyclone, and return ductwork back up into the shop, and locate the filter in the upper half.

I notice though that it appears that most Cyclones empty into the top of the cartridge

The Cyclone option, now with a bit more understanding, seems appealing, but much more expensive....

[Michael W. Clark]

Justin,
As Ian said, the 2HP could be marginal, especially if doing a cyclone. Ian was referring to pushing the clean air back into the shop from the filter. You could use the bag type or cyclone type with the open window concept your describe. The benefit of the cyclone is that it keeps your cartridge filter cleaner for longer resulting in a more uniform flow. You pay for it with additional HP required to overcome the losses in the cyclone. The cartridge filter on the bag type (without some type of pre-filter) can plug fairly quickly and reduce your flow and collection at the tools. The other benefit to the cyclone systems is that the fan is on the clean side, so you don't have to worry about larger peices tearing up the fan, they will drop out in the cyclone.

The cyclone after filters are made to go in from the top to make the cyclone filter arrangement as compact as possible. There is little performance reason to go into the top or bottom. In fact, most industrial collecters go from outside to inside and have an upward flow. On some, the filters lay on their side (Torit Downflo), but these are not good in high load applications.

Long story short, you could get the cyclone option and install the filter at or near the floor of your workshop. The elbow out of the fan could be rotated 90 upward and go into the bottom of the filter. The filter media does not care if it is right side up or not. The one downside to this I see if the fine dust that may fall off of the filter and back down toward the fan. For this reason, you may want to throw away the outlet elbow and put in a tee. The bottom of the tee could be made to accept the dust bin that would normally be located at the bottom of the cartridge filter. You can make the duct bigger on the outlet of the fan to reduce pressure losses.

Mike