Cyclone Venting

[Maurice Ungaro]

Hey all:
I know that the better filters, such as on the Oneida products get 99% of .02 to 2 microns. Question: would you still prefer to vent to the outside, or keep it interior with the filter provided?

I'm in the process of trying to design a better system that what I have, and would like to know your thoughts. I can easily put in a gable vent in my shop to provide positive airflow if I decide to exhaust through a wall.

[Phil Thien]

For me it would depend on heating/cooling issues. If I was able to inexpensively maintain my shops temperatures, I'd vent outside. If heating/cooling costs were a concern, I'd use filters inside. Just remember that conditioned air is what you're pumping outside.

The major advantage to venting outside is NEVER having to worry about cleaning your filters, and that even perfectly clean, new filters provide some resistance that reduces CFM.

[Bob Slater]

I am toying with the idea of using my Oneida 2HP as a an exhaust fan through an unused chimney beside the DC. To do this I would either have to modify the DC outlet just before the filter so that I could switch what would look like a giant throttle plate to divert air through some ducting. An alternative might be to fabricate a sheet metal housing to encase the filter when I want to vent the shop. I would think that 2HP motor would make quite the exhaust fan.

[Ed Labadie]

I vent outside, several reasons I went this way.

Cyclone is in an unheated part of the building.
Some machines are also in the unheated area (they aren't mobile)
No room for cyclone in heated area + didn't want unheated air being discharged in heated shop.
No filters made the system cheaper.
Minimum ammount of ductwork in shop, most of it is in the attic.

I did put a piece of hardware cloth (wire mesh) over the exhaust, this prevents tweety birds from flying inside the pipe and then getting launched across the yard. Although it could be fun to watch after a few beers.

The only other thing I've found is you need to keep all blast gates in the heated shop closed when not in use, the system will draw air outside.

Ed

[Matt Meiser]

I vent outside. Never had a problem with heating/cooling in a hobby shop. I just don't run the cyclone that big of a percentage of the overall time the heat/AC are on to make a significant difference and it has never caused a problem with my furnace which has a forced vent exhaust.

[Chris Padilla]

My next door neighbor would be MIGHTY unhappy should I have decided to cover his house in sawdust every weekend.... :D

[Ed Labadie]

My next door neighbor would be MIGHTY unhappy should I have decided to cover his house in sawdust every weekend.... :D

Thats only a problem if you have neighboors.. :p

Ed

[Matt Meiser]

Yep--even if the horses next door get lung cancer from my dust, I can always blame it on their bedding, also sawdust.

[Jeff Duncan]

Shouldn't be much dust outside at all if the cyclone is working correctly. Most of the dust is pulled out before the filters, that's the advantage of a cyclone after all. Certainly wouldn't be enough to cover anything with a layer of dust except maybe the area within several feet of the vent on a day with no air movement.
As far as venting outside, I think it's a no brainer if your not worried about heat or a/c. There's no advantage to keeping the same air in your shop if you can blow it outside and get fresh air in. Not going to happen up here in New England where I am though, that'd be way too much heat loss come January:(
good luck,
JeffD

[Victor Stearns]

I exhaust the DC outside as it is mounted to the outside wall of the workshop. I have yet to see any actual sawdust coming from the exhaust duct when using the cyclone.
I would however issue the same warning that someone gave to me, in that when I turn on the cyclone, and the shop door is ajar, the cyclone will create a vacuum in the shop to the point of opening the door. It you are using a gas or wood to heat the shop you will be pulling that air back out of the chimmey and into the shop. Thus when I use the cyclone in the cold weather I do crack the door open. When done it gets closed.
Victor

[Chris Padilla]

Shouldn't be much dust outside at all if the cyclone is working correctly.

Jeff,

Yes, very true except when you forget to check how full your bin is and stuff start going out the filters! DAMHIKT! :o

[Lee Schierer]

If you put the cyclone outside, you need to have an adequate air inlet into the shop for replacement air. The cyclone won't run efficiently if you are starving the inlets for air by trying to pull a vacuum in your shop due to poor inlet air volume.

[Maurice Ungaro]

Thanks for all the great views everyone. With my temperate climate in coastal S. Carolina, the heating is not THAT great of an issue, but it gets darn stifling here in the summer.

I'm still waiting to order myself a Dust Gorilla, and we'll see how the next few projects pay with regard to how much of that I get to keep for my future purchases (as opposed to going to the household General Fund :rolleyes:). Probably the option I will take is to just use the heigh tech filtration that comes with the machine, and see if that is sufficient. I can always vent outdoors later if necessary - what the heck, it's just another hole in my building!