Dust Collection - I don't sand. Do I still need a 2 stage collector?

[Will Boulware]

Yay! Another dust collection thread! Apologies, but I couldn't find anything that addressed my question directly. I'm open to advice based on personal experiences or scientific research either one, so fire away!

Quick rundown: 2 car garage shop, machines in a cluster in the middle, dust collector will likely be moved close to machines and attached individually with flex hose for now with an eventual goal of parking it ~8 feet away and running some very simplistic metal ductwork overhead. Everything is in a cluster, so I'm not expecting long runs of pipe. Easy answer is the Harbor Freight 2 hp model with the usual Thein trash can separator and a Wynn 35a filter that everyone seems to love, but after completing the 4 hours of required reading on Bill Pentz's site, I'm concerned that the airflow on the HF unit won't be enough to get "everything."

I'm interested in his recommendation, but I don't have the space for a 9 foot tall cyclone. In the ~1,000 actual cfm and 6" ductwork category, I've found a 2-canister 3hp model from Grizzly that seems to fit the airflow requirements, but I'm concerned about the constant filter clogging everyone seems to suffer from on single stage DC systems. Mr. Pentz indicates that the sort of airflow a 3 hp system can generate will quickly empty the trash can below a Thein baffle, thereby negating its effect. Given that I have a contractor's saw, a 14" bandsaw, and a lunchbox planer to pull dust from, and that I heavily rely on hand tools and do not use a power sander for anything, am I going to regret not finding a way to make a 2 stage system work? My understanding is that sanding dust is the major culprit in this filter clogging process, but that sawdust of any variant contributes as well even if the planer chips won't.

Also, I'm trying to future-proof this purchase as much as possible. If I upgrade houses, said dust collector will be moved outside, so I'd like something with as much pull as possible. Future machine upgrades will include a SawStop/Hammer slider and a bigger bandsaw, jointer, & planer that will doubtlessly be vintage iron and thus need a lot of airflow.

1. Is this 2 canister 3 hp system complete overkill for what I've got now?
2. Would I be better off with the modified HF unit for now and a "real" cyclone later? Or am I going to be ok with a single stage collector and my intended tooling?
3. Are my current machines so hopeless as far as dust collection goes that I should keep my shop vac and wear a respirator until I can upgrade both machinery and dust collection?

Thank you in advance for your help, and sorry for the long-winded, open ended questions. If you're the type to get your feathers ruffled by lengthy war-and-peace-esque forum posts, or by yet another dust collection thread, please respond with TL/DR or NADCT and I'll send you a picture of a goat for your troubles.

[John Donhowe]

Let me throw in my .02, since I am in a similar situation. I, too, came across Bill Pentz's website, which scared the bejeebers out of me regarding the health hazards of fine dust. I greatly admire and appreciate Mr. Pentz for the work he has done and the information he has provided, but I also realized that I cannot afford both space- and money-wise the DC system he recommends. My interpretation- such as it is as a rank amateur woodworker- of his design and dust collection in general is this:

My impression is that the Pentz design (high air flow, big cyclone, ramp, etc.) almost assumes that it is stand alone- that is, it needs to be of that scale to remove as much fine dust as possible on its own.

I believe that no matter how good your cyclone is, it's the quality of the filter at the end of the system that ultimately determines how clean your air is. So, with a good filter (e.g. Wynn nano), you don't really need, as you said, "to get everything".

In my mind, a reasonable compromise is to go with a Thien separator- much better than a single stage system, and near-Pentz cyclone performance, but a lot cheaper and more easily made. Okay, so a little more dust your filter, so you have to clean it more frequently. Personally, I'm willing to make that trade off.

I haven't seen what Bill Pentz said about a 3 hp DC emptying a Thien baffle. Far be it from me to argue with Mr. Pentz, but from what I've come across on the Thien web site, there shouldn't be that problem if the baffle is scaled appropriate to the DC size- just like cyclones, a bigger DC needs a bigger baffle. If you haven't done so, check out the Thien site- there's an extensive thread started by retired2 that has a lot of good info.

While I am highly suspicious of HF's claims of their DC performance, it would be adequate for your current needs, assuming you operate only one machine at a time. The big air hog for you now is the planer, and 3 hp would certainly be overkill, esp. with a cluster arrangement of your tools.

My suggestion would be to go with the HF with a Wynn filter, and build a Thien separator. When you move up to a bigger shop and longer duct runs, sell the HF on CL, and get a bigger DC- with Wynn (or comparable) filter(s), along with the separator of your choice (Thien or cyclone). As an alternative to the HF, think about looking on CL for a better DC. A couple of years ago I snagged a Jet "true" 2hp (it requires 240 volts because of the current draw) with a 1 micron canister for $200.

Keep your shop vac. You still need it for tools with small dust ports, such as routers and ROS- they can't use the high air flow that DC's provide, and need the high vacuum that shop vac give. Think about getting a Dust Deputy for your shop vac. I wear my respirator whenever I use my router- even with dust collection, a lot gets into the air.

Consider getting an air cleaner to help remove the dust that does get into the air.

I apologize for my long-winded reply

[Curt Harms]

I agree with a Thien baffle. I didn't do a stand-alone trash can with the attendant corrugated flexible ducting. That seems like it'd impose a fair penalty with plumbing and inefficient (in terms of air flow) flex hose. I put a Thien baffle in the funnel bottom of a Penn State dust collector and replaced the top bag with a Wynn filter. I still get some fine 'flour' in the filter but not nearly as much as before installing the baffle. I get pretty much no larger shavings or saw dust. I think any performance hit from having the baffle installed is offset by the filter staying cleaner longer. I also empty the bottom bag when it gets about half full. It's easier to maneuver when it's not as full. Will a HF type D.C. be adequate for larger machines? I have no experience there.

[Will Boulware]

Thanks for the replies! This confirms what I was thinking. Think I'll try the HF unit with a fancy canister filter and we'll upgrade when I have a machine big enough to warrant it.

[glenn bradley]

The cyclone keeps the filter clean, and therefor effective, longer. The separator will do this to some degree. The ability of the DC in use to overcome the hit that the separator puts on the airflow will vary with the separator design, fan curves and all that Voo-doo. Rule of thumb in my book is to buy the most dust collection you can.

[Ted Reischl]

I have a Jet, believe 1100? Too lazy to go look it up. Anyhow, the cannister filter on top has a paddle device that allows the pleats to be "cleaned". Works great. As to getting "everything"? Nah, ain't gonna happen.

The dangerous stuff is the fine particles, that is what needs to be sucked up. I also have a ceiling hung air cleaner. Every now and then I will forget to turn on the DC for the RAS and POOF, the shop is floating with fine dust. Turn on the ceiling unit and within a matter of minutes no more floating dust.

So, the moral of all this is that trying to get "everything" is not possible with one method, get an air cleaner to assist your DC.

Oh, and my big tip is: Do NOT sweep up your shop. Sweeping puts every fine particle of dust into the air. Vacuum it instead.

[Mike Heidrick]

Vacuum it instead.

Whats coming out of the exhaust port of your vac LOL.

[Prashun Patel]

I have a Thien separator. You can use a Super Dust Deputy. The cyclones usually come with better filters too, so make sure the one you have has one.

These pre-separators require emptying at about 75% to avoid adverse effects on airflow and your filter, so IMHO, it's worth it to design for quick changes.

I find too that there is no way to avoid manually cleaning the filters every so often - even with a separator.