Dust Collector Dilemma

[Bill Leung]

Hi all,

I have a question regarding dust collectors. Reading through all the past post has me more confused now then when I started. I need to get a dust collector for a smaller shop (10x20 single car garage) and am a hobbyist, I don't have the tools that make alot of dust (jointer, planer, oscillating sander) but hopefully will in the near future.

My question is this.
For single tool dust collection, will a 1.5 hp, 1100 cfm (jet or delta) be good enough (1 or 2 micron bag)?

Will you need to put on a Wynn filter anyway (adds another $80-$100 to the price).

With the total cost coming to around $500, does it make sense to get a lower end Cyclone with cost $800+shipping which brings the price to $1000.

Thanks in advance.

[Brian Dormer]

The 1.5 hp should be more than you need for a single tool. Since you are a hobbiest with limited space you might want to consider one of the .75 to 1 hp DC's. Also plenty of power for a single tool. I outfitted mine (c-man - purchased on sale) with a .3 micron from Grizzly and it works great.

I think the $1000 unit, for your application is probably extreme overkill.

[Wilbur Pan]

My shop is also 10x20 and in a basement, so my air issues are probably worse than yours, as you should be able to open a door and/or windows.

I bought the JDS Dust Force dust collector (also 1.5 HP, allegedly 1250 CFM, 1 micron bag) and a JDS 750-ER air cleaner. The Dust Force doesn't take up that much space. The two in conjunction seem to be doing well with controlling the dust. Total cost was $600 at a Woodcraft 10% off/free delivery sale.

Remember, the dust collector only has one shot at collecting dust, and that some will escape, despite the most heroic efforts at building the ultimate cyclone system. That's where the air cleaner comes in. You'll have the luxury of opening the garage door or a window, which is the best method of clearing dust from a room. But I would get both.

[James Leonard]

Hi,

I am putting my main dust collector outside which is a one horse chinese 110V job with a one micron filter. Since it is generally conceded that this will not have enough 'suck' to pull stuff from a jointer or drum sander over a distance I am going to try cheap and small Harbor Freight mobile units without bags to 'pump' the main hose. By this I mean I will connect the input of the small motor blower to the tool and the output to the long run of hose going outside to the dust collector. I cut many things on my CNC tools that produce harsh sub-micron dust, IMHO it is not possible to really filter this, so I REALLY want to send it outside into a storage shed I have set up.

-James Leonard

[Mark Engel]

I think Harbor Freight Tools is probably a bad word around here, but...

This is the dust collector I am currently using. The main thing I don't like about it is it only runs on 110v (so 2hp is probably a stretch).

What I do like about it is it works very well. I have it piped in to all of my machines with 4" blast gates at each one. I also have a trash can mounted chip separator. I was able to pick up some felt .1 micron bags for it on ebay.

It is only 200 dollars. I got it on sale a while back for $159.99.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=45378

[Bill Leung]

Thanks for all the replies, I already have a Jet air cleaner which I noticed cleans up the ambient air pretty nicely. I have been using my Fein vac for dust collection and that has been marginal on the TS and BS.

Although I know alot of people use the "bag" dust collectors, everyone seems to want a cyclone. I haven't read too many post stating that the bags do a great job at dust collection which is why I posted my question.

I know the cyclone has many advantages over the bags but do the virtues warrant the difference in price? I guess I don't want to be buying a cyclone in a year after buying the bag system.

[Rick Moyer]

I can't help you with answers, Bill, but I have some similar questions I'd like to ask here as well. (I'm sorry if this seems like a highjack, but maybe my questions can help with your thought process, too!).
It seems to me there are two main issues with dust:
1. having to clean it up around the shop
2. breathing in dangerous dust
I would like to know opinions(or facts) as to what is nececssary to keep things relatively clean in a small shop: e.g., is the type of unit Bill asks about adequate to hook to one tool at a time and do a good job? In other words, what is necessary at minimal costs <$500 to do this.
Secondly, is this minimal outlay somewhat futile in controlling dangerous dust particles and if so, how much does one need to spend on what for safe breathing. I don't want to have premature lung issues, but also can't seem to justify more $$ in dust collection than any of my tools. (but I may be wrong). Sorry for the intrusion of your post Bill.

[Tom Maple]

Bill,

Having recently re-entered the woodworking hobby I have also wrestled with the dust collection issue and found a site put together by Bill Pentz to be extremely helpful. It is not a quick overview. He has very detailed information and designs for building your own cyclone.
Being older (and hopefully wiser) I have tried to follow his guidelines.
This may be overly simplified, but the bottom line appears to be if you don't use a properly designed cyclone, it is no better than other systems. It will just push the dust around your shop, even if you use a cartridge filter.
If you can't use a good cyclone system you are better off using a 2 hp collector and exhausting it outdoors.
Remember, it's the small, invisible .5 micron dust that is the most dangerous to your lungs.
Good luck,
Tom

[terry sligar]

i bought a harbor freight dc and put a wynn filter on it and piped it all over my shop and it reall does do a nice job.

[EJ Gowlovech]

I've looked at Bill Pentz' site and there is a lot of info there. Almost too much. Does anyone have any "easy" cyclone plans that one could add to their existing DC system? I have the Jet 1100 1.5 hp system, and usually just move the hoses around, but I would like to get a system going in the shop (aka garage) so I don't have to keep stepping around everything.

Any info would be greatly appreciated.

Thanks,

E.J.

[Wilbur Pan]

I know the cyclone has many advantages over the bags but do the virtues warrant the difference in price? I guess I don't want to be buying a cyclone in a year after buying the bag system.


It seems to me there are two main issues with dust:
1. having to clean it up around the shop
2. breathing in dangerous dust
I would like to know opinions(or facts) as to what is nececssary to keep things relatively clean in a small shop: e.g., is the type of unit Bill asks about adequate to hook to one tool at a time and do a good job? In other words, what is necessary at minimal costs <$500 to do this.
Secondly, is this minimal outlay somewhat futile in controlling dangerous dust particles and if so, how much does one need to spend on what for safe breathing. I don't want to have premature lung issues, but also can't seem to justify more $$ in dust collection than any of my tools. (but I may be wrong). Sorry for the intrusion of your post Bill.

All the information you need is on Bill Pentz's website, but even as an advocate for paying close attention to dust collection needs I'll even say that Bill's site is kind of a "drinking from a firehose" experience. I had to read it through more than a few times before I was able to wrap my brain around this issue.

Having said that, I think I can simplify things a bit.

1. The dust you need to worry about is the 1-10 micron particles. This is the stuff you can't see. This is the stuff that will kill your lungs. There isn't a real "safe" level of dust exposure for the smallest particles.

2. There are two ways of trapping this dust: collecting it at the source (dust collector/cyclone system) and filtering the air (air cleaner).

3. The way to get the fine dust at the source is to move air -- lots of air. The only way to do this is with motors that have enough horsepower and blower fans that are big enough. Don't think that because your DC can get at the chips, you're doing a good job. It's easier to suck up chips than fine dust.

4. The way you measure air flow is CFM. More CFM is better. For a list of CFM needed to collect dust from various machines, see this table on Bill Pentz's website (http://billpentz.com/woodworking/cyclone/DC4Dummies.cfm#CFMRequirementsTable). Note that you'll need up to 700-1000 CFM for some machines to collect the fine dust.

5. Dust collectors come with CFM specs. These specs are, ummm, optimistic at best. Large motor + large blower fan = lots of CFM. That's the only way to get it. Or, as Scotty used to say, "I canna break the laws of physics!"

6. What works against the CFM spec that comes with your machine is the fact that by running ducting from the machine to the dust collector you add resistance, and therefore lower the CFM.

7. The things that will add resistance are narrow ducts (< 6") and long ducting runs.

8. The other thing that will decrease your CFM is clogging whatever filter (bag or canister) you are using on your dust collector with dust as you use it. The way to prevent your filter from clogging is with a cyclone separator, which will also add resistance to your system, which will drop your CFM yet again. This is one reason why cyclone systems come with larger motors and larger blower fans than regular dust collectors.

9. No matter how great your dust collector/cyclone is, you can't get all the dust at the source. So you need some sort of back up plan to get the airborne dust.

10. Your two options for the back up plan are: opening a window or door (which is the best option by far), and running an air cleaner.

11. If you run an air cleaner, you need to get enough CFM for your room. Conventional wisdom says to exchange the room volume about 6-10 times an hour. Much better is to aim for 25 air exchanges per hour. You'll clear out the airborne dust much more quickly.

As I mentioned above, I have a 1.5 HP/11" blower fan non-cyclone dust collector and an air cleaner. The way I get around the issues of duct resistance is I move my dust collector from machine to machine and use a very short run of flexible duct (8 ft. of 4" duct hose). This should still give me around 800 CFM. If you plan on a more permanent ducting system, you're going to need a 3-5 HP motor and a 14-15" blower fan to get around the duct resistance.

[Bill Leung]

No hijacking worries here Rick.

All, Thanks for your responses. I've read Bill Pentzs' site (many articles a few times). There is a lot of good information on the site and as a Mechanical Engineer, (no expert in air filtration), I agree with his comments/ facts. The reason I have not gone out and bought a cyclone is the following:

1) Bill's site states that a cyclone is more effective because it get's the heavy particulates out of the air stream leaving only the fine dust for the filters. Even then, the recommendation is to filter outside for both systems. The cyclone is more efficient because it makes the filters more effective and efficient. Is this really the advantage since the bag dust collectors do a fairly good job at collecting the big stuff as well? From articles and such, even industrial cyclones exhaust to the outside, which seems to be big advantage. Will staying on top of cleaning/replacing filters be just as good?

2) His site recommends 1100 cfm models from Jet and Delta. They provide 800cfm at the tool which is what is required to be effective. I know that more HP can move more air but for a smaller shop is this really a problem.

I just want to make sure I'm not missing something else before making my decision. I'll be the first to admit that if I spent a $1000+, I'll be telling everyone it was money well spent regardless. I just got to thinking that will a good dust collector, air filter and maybe a mask, especially for the dust intensive jobs be just as good especially if you throw the exhaust outside.

[terry hansen]

Like you I suffered the same dilema. I used a mobile 1 1/2 delta DC and moved from machine to machine. After wading through Bill's website and understanding about 1/2 of it, I finally rationalized the purchase of a cyclone, ducting and ambient air filter as another tool to make my "hobby" more enjoyable and safer. I was able to locate entire unit outside workshop so dust filter doesn't vent back into shop (living in FL helps one not worry about cold). This works well for me and I realize it may not fit your situation, but if you consider a DC another tool and use the same criteria as selecting a TS or (insert favorite next tool here), it helped me put the process in perspective.

[Rick Moyer]

Wilbur, thank you for consolidating the volumes of info. It all makes better sense to me now and I think I can decide what I should do.

[Kelly C. Hanna]

Get the biggest and best one you can afford....it's kind of like shop space.

[Marc Prudhomme]

Bill,
Just remember that if your machines do not have a 4'" dust port then you will have to modify them or you wont get the full cfm rating on all that money you spent.
I bought the Delta 1 1/2 HP with 1 micron bag at woodcraft on sale for 200.00.My rigid tablesaw onl has a 2 1/2 dust port,so I bought a reducer to hook up to the Delta.Well aparently I am not getting the full CFM from my Delta now unless I jump through hoops and ladders in modifications.
If I could do it all over again I would buy high end shop vacs for each machine.
ITS A GIANT P>I>M>A
Marc
P.S.
Please,no one send me any links on how to modify my saw.I HAVE THEM ALL and I am not interested

[Cliff Rohrabacher]

That to my mind is the dilemma. If a DC isn't trapping and filtering particles all the way down to something less than One Micron it's a Dust Pump.

To get that level of performance from a DC you will pay a lot. You can build one cheaply enough but you'll still need a powerful and noisy impeller and motor.


If you are going to try and do DC on a budget you might first want to consider whether you want to clean the air you are breathing or whether it's the crap that builds up under the saws etc.

For my money (and space) I'd rather clean the air and sweep or vacuum the chips. There are a lot of guys who built their own air filters from plywood using slide-in air filters using progressive filters down to less than 1 micron. they use squirrel cage fans (which are pretty quiet) and usually hang 'em from the rafters to catch the air borne dust particles.

One micron and smaller is the size that can enter the blood stream through the lungs ( or so I am informed).

[Bill Leung]

Cliff, I already use a Jet air filter and I did notice a big difference in air quality.

Marc, my TS and BS have 4 inch ports so that isn't a problem. To your point, Dust collection is a system and only as good as the weakest link. If you don't have sufficiently sealed hoods on your machines, a lot of the fine dust might not even make it to the DC.

You guys are addressing my original question. I wanted to know if the 1100 cfm DC's are good enough for a small shop or would it still be not sufficient once the filters start getting clogged. It seems like the cyclones move more CFM with lower HP and need less cleaning which are pluses. My main concern is reading articles like in the FWW shops edition, they listed a 1.5hp only being sufficient with a 4ft flex. In my mind that sounds to me like your DC needs to right up against the tool which is not always convenient or possible. I could live with 8-10ft as that would be more workable in a small shop. This prompted my post...are these "bag" DC's just a band aid.

Another point that you guys are bringing up is the environment. Dust collection in a basement shop is much different than a garage that you can open doors and windows. The requirements seem to be much differenct for those cases.

[Wilbur Pan]

Bill,

One of the things you'll find on Bill Pentz's website, if you haven't already, is an Excel spreadsheet that calculates the resistance of the ducting plan you have.

If I plug in the numbers for my setup (8' of 4" flex hose directly to a machine), the resistance is minimal -- about 3 inches of static pressure. Since the static air pressure is so low, a 1.5 HP, 11" impeller, 1100 CFM dust collector should be able to pull 700-800 CFM against that level of resistance.

My conclusion was that an 1100 CFM unit was good enough for a small shop, IF you used short duct runs (8-10 ft of 4" flex hose) and IF it was used in conjunction with a secondary dust clearing system, like an air cleaner or open windows/doors.

I think that the Fine Woodworking recommendation of a maximum of 4' of 4" flex hose is based on the 1100 CFM dust collector being the only unit collecting dust -- no air cleaner, no open windows.

It's best to think of dust collection as a system. Even if the dust collector can't trap all of the dust, having one will make it easier for the air cleaner.

[Brian Kent]

I got the Delta 50-760 for the same size work area. I have had it since December and have much happier lungs and wife.

I got it after reading as many reviews as possible. The clincher was that it already has a 1 micron shaker felt bag. I am sensitive to dust and have had a much better experience with this in place. I still use a respirator when using tools that don't connect to the Delta (such as buffing with diamond dust) and a Jet air filter when there is ambient dust.

[Bill Leung]

Thanks everyone, this has been a good discussion. Sounds like you guys have had good success with the bags. This certainly helps with my decision.

The other factor in this whole equation is that if I eventually get tired of tripping over ducting and moving the DC around the shop I would need a cyclone as the 1100 cfm models will not be sufficient to support permanently plumbing. If a good bag DC is going to cost a minimum of $400-$500, maybe a cyclone might be justified if the bags have limited usefulness.

[Wilbur Pan]

Bill,

You don't have to spend $500 on a dust collector. My JDS Dust Force lists for $350 at Woodcraft. On sale, I got it for $310 and free shipping. Amazon lists it for $300, plus shipping, but they also have free shipping sales every so often.

The Delta 50-760 that Brian mentioned goes for $300-350. The only reason I didn't get that machine is because I have low ceilings in my basement which would not accommodate the height of the bag on that machine. Otherwise, I would have gotten the Delta machine instead.

If you are concerned about costs, remember to factor in the cost of permanent duct work if you go the cyclone route.

As far as moving the dust collector around, my shop is arranged so all the machinery is at one end, which allows me to park the dust collector at that end and just move the flex hose from machine to machine. If your machinery is placed across your 10' x 20' shop, then placing the dust collector in the middle of the shop would be an ideal spot.

[Bill Leung]

Wilbur, I know the pricing of the DC itself will run 350ish. I'm including the cost of a Wynn caninster which adds another $80 plus shipping etc. That's how I get the price to $500. The Jet 1100 cfm 1.5 hp is even $450 on the current sale. I guess the question is are the stock 1 micron filters that come with these units adequate? From Bill's site, it doesn't sound like it which is why I added that into the price.

My garage has 8ft plus ceilings so I'm good on height. As far as big powertools go, I currently only have a TS, CSMS, and BS so moving around the duct should not be an issue but when I get the router table, jointer and planer, that may make it a bit harder to squeeze things to one side. My thought around the cyclone is that I could still run flex line until I figure out the shop layout and then start laying permanent plumbing when I have all the main tools.

Cost is always a concern but not really the reason for the post. I am trying not to upgrade equipment after a short time though and be smarter that way, saving money in the long run. Even if I bought a DC for $300, if I were to upgrade, I wouldn't get more that $150 on resale.

My question was really targeted at determining whether the DC can really do the job (within reason). It sounds like from Bill's site and magazine articles, their effective operating window is pretty small. Although I believe there is merit there, I found it hard to believe that these systems don't perform as I know just from this forum that 100 or 1000's of WW's like yourself are using them successfully and not scraping them to buy a 3hp+ cyclone. Since I don't have a DC yet, I have the luxury of going either way. It helps a lot to hear that people are in fact doing fine with the $300 models and not coughing up a lung after a wood working session. I started thinking about this post after reading what people are saying about the Sawstop. People can justify spending 5k or to prevent loosing a hand or finger, so I started thinking why is dust collection any different. How much are we willing to spend to save our health? I know many on the site recommend cyclones but unlike saws which you know will cut wood great without the safety features, do the non cyclones, do just as good a job (without the maintenance).

I am not trying to justify a cyclone but trying to find out if the bags can match up and do the job.

[Ray Phillips]

I went through this process about 3 months ago. I have a small shop 13x30. I have all my equipment on wheels. I ended up purchasing the Jet 1100 DC and the 750 air filter. I placed the DC in the center of my shop against a wall and ran 4" PVC ducts with blast gates to my RAS, BS and router table. I then ran a duct across the shop to the other side 13 feet to my mini lathe and sanders. Since I am just a hobbiest and not a pro I can only use one machine at a time. When I use a particular machine I open that blast gate only. This system has worked very well for me. If I had a larger shop I would have purchased a cyclone system, but I am very happy with what I have now. It beats a broom and dust pan and a shop vac.

[glenn bradley]

I'm in approx. 20 x 30 feet of gara . . er, shop. I have a 1HP Delta with a second stage trashcan. Along with the fact that I can open the garage door and the side door, this little guy does a good job on one tool at a time. If I were in an enclosed space or couldn't open the 'wall' and get flow through ventilation I am sure it would be inadequate.

There's a cyclone in my future (at least in my mind) and plans to re-deploy the 1HP to fixed duty on whatever tool seems to make sense as the shop progresses. For now, my environment, as described is very workable.

[Wilbur Pan]

I am not trying to justify a cyclone but trying to find out if the bags can match up and do the job.

Bill,

Long story short, the cyclones certainly will do a better job, but I think that the performance benefit for a small shop is minimal.

I certainly don't want to discourage you from getting a cyclone system if you have the budget and space for one. However, I don't worry so much about the performance of the 1 micron filter bags that come with the 1 1/2 HP dust collector systems out there. There are two reasons for upgrading the filter. The first is that the bag may not be truly be a 1 micron filter, so that you are pumping 1 micron dust throughout your room. This would be a concern only if your dust collector is the only way to trap dust in your workshop. The fact is, even the best cyclone system can't trap all the dust at the source. If you do a search here on SMC, you'll find a thread outlining the fact that even high quality cyclone setups will result in airborne dust (http://www.sawmillcreek.org/showthread.php?t=44601). If this is the case, I'm not going to worry too much about the performance of the bag in a 1 1/2 HP dust collector, as long as it's a 1 micron bag. Instead, I would concentrate on plan B (ways to trap dust that the dust collector missed), be it a high quality air cleaner or opening doors and windows. Furthermore, as the bag gets caked with dust, it will trap finer and finer particles. I agree that Wynn makes excellent filters, but I have not seen the need to upgrade my dust collector bag. If I was going to do any filter upgrading, it would be in my air cleaner. I do think that upgrading or adding air cleaner units is the most cost effective way of increasing the collection of fine dust, second only to opening windows.

The second reason that there are concerns about dust collector bags is the thought that as they become caked with dust, the performance of the dust collector will drop. However, the resistance of your ducting will have a far greater effect on dust collector performance than how clogged your filter bag becomes. The impact of a clogged dust collector bag would be decreased ability to trap 100% of the fine dust at the source, but as we've already established that this is not possible, we're back to dealing with plan B again.

If you have the budget and space for a cyclone system, I would go for it. The main reason I don't have a cyclone is that I did not have the space for it, not budget. If you decide that you need to go with a 1 1/2 HP 1100 CFM system, as long as you can keep ducting runs short, I wouldn't lose too much sleep over it. In either case, I would concentrate on plan B -- air cleaners and/or windows and doors.

[Steven Wilson]

You guys are addressing my original question. I wanted to know if the 1100 cfm DC's are good enough for a small shop or would it still be not sufficient once the filters start getting clogged.

The typical 1100 CFM bag collector (which is free air CFM without any bags or duct attached) runs at about half to 2/3 of that CFM which means it's marginally able to collect from machines with the needed 600-800 CFM of flow at the DC hood. If you hook it up to a bunch of pipe it won't be sufficient. As for filtering capacity, the typical bags sold are useless for filtering the fines. You either need properly made bags (which will have a lot more filter area and reach your roof) or a pleated cartridge. So, a Jet DC1100C using a short segment of 6" hose will work quite well on many hobby machines if you wheel it from machine to machine.

2 1/2" and 4" machine ports are generally there for marketing, not your health, and aren't designed for proper collection. You will need to redesign and rebuild these ports if your serious about dust collection.

Your lungs breath the same air that Air Cleaners are cleaning. For filtering fines while you're working air cleaners are useless. To clean up ambient air prior to finishing air cleaners are usefull. Air cleaners will not help your lungs at all.

If you can't collect it properly at source wear a respirator.

[James Hebert]

I recently installed a Harbor Freight 2hp unit for a 1 car garage size hobbiest shop. I ducted allt he stations with 4" sewer and drain PVC and plastic Jet blastgates for each station. I have 6 stations/blast gates and the farthest about 20ft from DC. I normally open one gate for a machine but on occasion get lazy and keep the tablesaw and the chop saw gate open and stillt here is plenty of plenty of suction. I also installed the Wynn Environmetal filter which improves the HF 30micron 30sqft filters to 0.5 micron 300sqft filter with clear plastic collection bag. It works phenomally well and im sorry I didnt do this years ago. Prices paid are below:
HFDC $134 on sale and with 20% off coupon, 2hp 1600cfm
Wynn kit $91 (mail order)
4" pvc sewer and drain (Lowes) about $0.70/ft and fittings about $1.25 ea.
Jet Blastes gates from Amazon, $1.50
Some flex hose. Rockler has the best clear flex hose.

The HFDC is identical to the Delta, Jet etc 1.5 hp 2 bag units from same OEM but at 50% or less the cost.

[Bill Pentz]

Bill,

I slipped my answers into your questions in blue, plus added some background after. Hope this helps.

bill


Hi all,

I have a question regarding dust collectors. Reading through all the past post has me more confused now then when I started. I need to get a dust collector for a smaller shop (10x20 single car garage) and am a hobbyist, I don't have the tools that make a lot of dust (jointer, planer, oscillating sander) but hopefully will in the near future.

My question is this.
For single tool dust collection, will a 1.5 hp, 1100 CFM (Jet or Delta) be good enough (1 or 2 micron bag)? The 1.5 hp dust collectors are great for “Chip Collection” meaning collecting the same sawdust and chips we would otherwise sweep up with a broom, but almost always lack both the airflow and filtering needed for good fine dust collection. The issue is with a good 6” smooth walled flex hose going to a tool with two ports like a table saw with a cabinet port and blade guard port we still pull about 3.6” of resistance with a clean filter. As the filter builds up a cake of dust the resistance pressure can easily rise to over 6”. At 6” pressure these blowers with 11” diameter impellers only move about 425 CFM. Although we only need about 350 CFM for good “chip collection” to keep our shops look clean, decades of professional engineering shows we need 800 to 1000 CFM at our larger tools to ensure capturing the fine airborne dust. With dust lasting six months to years before it dissipates or breaks down, in an enclosed shop the dust that we miss during collection or that goes through our too open filters will build to very high levels. Airflow from our tools, fans, dust collection systems, air compressors, etc. will launch this “fugitive” dust over and over. Since most of this dust is smaller than 10-microns, roughly one tenth the thickness of a human hair and we can only see down to about 10-microns, it is invisible. The result is we end up with clean looking shops that create a false sense of security because the airborne fine dust levels just keep growing to dangerously unhealthy.

Will you need to put on a Wynn filter anyway (adds another $80-$100 to the price). I have long recommended replacing all of the more open filter bags with a good cartridge filter. Unfortunately, if you don’t also do some serious pre-separation, these cartridges are going to clog, pose a constant cleaning problem, and need replaced roughly every 300 hours of use. Filter material makers recommend at least 1 square foot of filter area for every 2 to 4 CFM of airflow to prevent 1-micron and finer filters from loading up too quickly. A typical dust collector bag has about 30 square feet of area, so these are going to load up and become a constant cleaning problem. This loading kills our airflow by adding lots of resistance, plus rapidly ruins filters from excess cleaning and the increased pressure forcing the sharp particles to cut and tear their way through the filter pores. The exception is of course vendors that instead provide 10 to 30-micron filters which load up far more slowly. Sadly, many vendors play games with filter ratings. The standard set by ASHRAE is indoor filters need measured when clean and new. Most of the filters found on small shop dust collectors and cyclones are measured after the filter has become plugged or at least fully seasoned meaning built up a heavy cake of dust in the filter pores that does not come out with normal cleaning. That dust improves filtering, but kills our air flow unless the filters are big which is near impossible to achieve with a bag or smaller cartridge. Adding enough dust to any filter will eventually get any desired level of filtering, but we also lose our airflow needed to collect the dust. So to answer your question I personally use a large Wynn all poly cartridge filter on my Jet DC-1100 or use my cyclone with its fine filters. I also always use an exhaust fan sitting in a doorway, plus wear my 3M NIOSH approved mask whenever making fine dust.

With the total cost coming to around $500, does it make sense to get a lower end Cyclone with cost $800+shipping which brings the price to $1000. My own testing shows most small shop cyclones are “chip collectors” that have fine filters added. Since these separate little better than trashcan separator lids, I don’t recommend them unless you can forget the filter and vent directly outside.
Thanks in advance.

Bill,

We have three major approaches to dust collection today.

There are no standards enforced for small shop dust collection, so whatever we will buy is what we get.
For shops in commercial buildings subject to regular fire marshal inspection most must comply with local fire and building codes which mostly come from the National Fire Protection Association (NFPA) guidelines. These guidelines cover a wide range of areas which many call “chip collection” meaning picking up the same chips and sawdust that we would otherwise sweep up with a broom. Dust collectors and cyclones need certified as fire and explosion proof or instead put outside. The cost for certification is expensive, so most put their dust collection outside.
Fine dust collection maintains minimum air quality standards compliant with either OSHA, ACGIH, or medical air quality standards used in Europe. OSHA only regularly tests the air quality in the largest woodworking facilities with many workers, so most shops have no enforced standards.

Both “chip collection” and “fine dust collection” have decades of engineering and refinement shared to define exactly what is required.

Chip collection has been done for over sixty years and is well understood. For good “chip collection” we need:

Hoods which block and trap the dust being ejected from out blades, bits, and cutters. Our tools tend to launch dust and chips at over 100 miles an hour and our dust collection airspeeds are more like 40 miles an hour so if a hood is not well designed and in the right place, the dust is going all over.
Roughly 4000 feet per minute (FPM) airspeed with about 350 cubic feet per minute (CFM) air volume will effectively pick up the heavier sawdust and chips.
Ducting with a cross sectional area equivalent to a 4” diameter duct will carry this much airflow at the needed internal ducting speeds.
An internal ducting airspeed of about 3800 FPM in vertical runs and about 2800 FPM in horizontal runs to keep the dust entrained, meaning kept airborne. Dust that settles in a duct poses a serious fire risk. When these piles break loose they can damage blower impellers, motor bearings and filters, plus the sudden surge of dust when a duct pile breaks loose creates one of the few instances where a small shop can create a potentially explosive dust to air mixture.
Open filter bags that trap particles sized larger than about 30-microns where 30-micons is about one third of the thickness of a human hair. Most airborne dust that does not quickly settle is sized 30-microns and smaller.
The 30-micron filter bags need a minimum of roughly one square foot of filter area for every 20 CFM of airflow to keep from clogging too quickly, so a typical small shop 350 CFM dust collector needs at least 16 square feet of filter area. Doubling the filter area will cut both cleaning and resistance four fold so most small shop dust collectors come with two bags for roughly 30 square feet of filter area.
Chip collection in compliance with normal building and fire safety codes will use all grounded metal ducting, metal instead of cardboard chip collection, and put all dust collectors and cyclones outside that are not certified to be fire and explosion proof.
Note: Using finer filters can pull off the fine dust collected, but does not move the air needed to collect much of the fine dust. Fine filters have far more total open surface area due to the fine filter strands blocking less air, so a new fine filter will move far more air when the filter is clean and new. Unfortunately, this is only a temporary advantage. As fine filters season with a permanent cake of dust in the filter strands that does not come out with normal cleaning resistance increases significantly over more open filters. Fine filters require far more filter area or lots more cleaning. Many vendors confuse this issue by selling fairly open filters which trap much of the visible dust while passing the unhealthiest 10-micron and smaller fine dust. This lets them get away with cartridge filters that only have about 1 square foot of filter area for every 10 CFM and not force too much cleaning. Meanwhile the unhealthiest invisible dust blows right through and begins to collect in our shops soon creating clean looking shops with dangerously unhealthy airborne dust levels. With cyclones that separate off most of the 30-micron and larger particles, open filters can take months to years before they actually provide the vendor advertised filtering. Most who use fine bag and cartridge filters on typical dust collector and cyclones end up being very unhappy with the increased need for cleaning, much worse overall airflow and often poor filtering.


Likewise, fine dust collection has been done for decades and is equally well understood. The tough part is ignoring hobbyist and small shop “chip collection” advice and staying focused on professional firms whose customers must pass regular air quality inspections. Fine airborne dust spreads so quickly that decades of testing established there is almost zero chance of either an exhaust fan or air filter pulling down the dust level fast enough to avoid failing an air quality test. I use a good air cleaner as it helps with the inevitable dust missed during collection and it saves on dust ruined finishes. Regardless, this means we either figure out a way to collect the fine dust at the source or we will not have good fine dust collection. Festool and a few others have shown that by using tools designed from the ground up with good fine dust collection built in to totally contain the fine dust a good shop vacuum provides ample fine dust collection. Unfortunately, most of us instead use larger tools which are copies of units made often without even good “chip collection” built in. For good fine dust collection on our traditional tools that captures the fine dust air engineers have found we need:

Hoods which block and trap the dust being ejected from out blades, bits, and cutters. Plus our hoods must also contain the fine dust that is often launched from other parts of our tools. I did extensive air quality testing during the last quarter of 2006 and not one single shop passed its air quality test at any level regardless of the size of cyclone or dust collector if the table saw did not have a good blade guard dust hood that blocked the fine dust from being ejected.
Roughly 4000 FPM airspeed to effectively pick up the heavier sawdust and chips, plus roughly 50 FPM airspeed all around the dusty portions of our tools to pull in the fine dust before it can be spread by normal room air currents. We have to provide that 50 FPM over a large area. From using our vacuums we know that sucked air which comes from all directions maintains its air speed for only a very short distance. To cover a larger area we need to move lots more air. Careful testing shows that our larger tools need about 800 CFM to pull in enough dust to meet OSHA air quality standards. We need about 900 CFM at our larger tools to meet the five times higher ACGIH standards that most commercial firms voluntarily follow. And, we need about 1000 CFM to meet the fifty times tougher than OSHA air quality standard that pulmonary doctors recommend which is already the standard in the European Union.
Ducting and tool ports with a cross sectional area equivalent to a 6” diameter duct will carry the 800 CFM required to meet OSHA air quality standards. We need either a higher pressure blower or ducting sized 7” in diameter to meet ACGIH and medical air quality standards.
An internal ducting airspeed of about 3800 FPM in vertical runs and about 2800 FPM in horizontal runs to keep the dust entrained, meaning kept airborne.
We need roughly 2-micron filters to meet OSHA air quality standards, 1-micron filters to meet ACGIH air quality standards and 0.5-micron filters to meet European Union and medical recommended air quality standards. The filter material maker tables show at the OSHA 800 CFM and 2-micron filter level we need a minimum of about 100 square feet of filter with most recommending at least 200 square feet or more. At ACGIH 900 CFM levels and 1-micron filters we need more like 150 square feet of filter with most recommended at least 300 square feet or more. At medical air quality 1000 CFM levels with 0.5-micron filters we need more like 200 square feet of filter with most recommending at least 400 square feet or more. And yes, I am fully aware that this is a controversial area where many claim half as much will work just fine. Half as much filter area will work but you then need to replace expensive filters four times as often.
Like chip collection good fine dust collection in commercial facilities subject to fire marshal inspection also requires compliance with normal building and safety codes using all metal ducting, metal instead of cardboard chip collection, and putting all dust collectors and cyclones outside that are not certified to be fire and explosion proof. If we build good systems that keep up enough air speed to keep all clear, the science and physics shows that we can use plastic ducting, cyclones, and other components, but I still recommend use of metal collection bins in lieu of cardboard bins simply as a good fire prevention measure.


As you can see, there is far more to good fine dust collection than "chip collection". I recommend you spend the time on my Cyclone and Dust Collection Research (http://billpentz.com/woodworking/cyclone/index.cfm)web pages to figure out what is most appropriate for you.

bill

[James Hebert]

itll work fine and even more then you need. Just put a 20 gal trashcan for chip collector before the impeller and it will difuse the chips and so heavy loads like from planer wont be a problem at all. Dont get sucked into the dust paranoia/fanatic dilusions. The $ spent for what they claim is minimal will buy you .01% improvement over the $135 2hp 1600cfm HF DC. The Wynn $91 filter is nice, but the 30 micron bags that come with the unit will suffice just fine.

[Justin Henry]

If you have 220 ..... for penneys more than the HF-Wynn combo I'd go this route anytime.

http://www.pennstateind.com/store/dc2000b.html

Check size of impellors, cfm and bags. Willing to wager the thing is at least 75% stronger, probably more. But 120 would be problem.

Not knocking the HF combo - many are very happy with it. This just has more juice. But needs the juice to it to do it

[Bill Leung]

All, your input and opinions are much appreciated. It is interesting to hear the different views of those who have lived and Breathed the experience.

Bill, thanks for the additional information, like your website, I will need to read your post a few times.

So it sounds like you use an Jet 1100 cfm DC with a Wynn filter as well as a cyclone. I take that as a recommendation for the Jet. Your comment regarding small home cyclones as chip collectors is one of the reasons I was getting confused from all the write ups. I was concluding that the main advantage of the cyclone is that you would have less cleaning and more consistent airflow. It's encouraging to know that the trash can separators do a good job. As a weekend warrior, 300 hours of operation could sadly take a year to hit. I have the air filter so supplementing that with a 1100 cfm DC and trash can cyclone might do the trick especially if I exhaust outside.

[Burt Alcantara]

Bill,
There are a few non-scientific issues to consider. If you really like woodworking you will eventually end up with more tools then you'll ever be able to use. It's like moving into a new house. This year: What will be do with all that space? Next year: Were'd all this stuff come from?

Dust collection is a very subjective matter. I bought the Harbor Freight on sale for $150 or so. Put a Wynn filter on it. Never captured enough dust for me. There was always a film of dust on the collector and everywhere else. This, in conjunction with the JDS ambient filter. The real test as far as I was concerned was watery eye, sneezing, coughing and an unpleasant feeling in my lungs.

I began wearing a cartridge mask. Helped enormously. Sold the HF and bought the small ClearVue - CV1400. There is no dust anywhere near the cyclone. This is 5hp with a 15" impeller. My filters (Wynn) capture .5 microns.

I don't cough or sneeze. My only problem now is getting the shavings from turning under control. They go everywhere.

Hope this helps,
Burt

[Bill Pentz]

Bill,

You are most welcome. I again put my two cents below in blue.

bill


All, your input and opinions are much appreciated. It is interesting to hear the different views of those who have lived and Breathed the experience.

Bill, thanks for the additional information, like your website, I will need to read your post a few times. You are most welcome

So it sounds like you use a Jet 1100 CFM DC with a Wynn filter as well as a cyclone. I take that as a recommendation for the Jet. Yes, I think the Jet is a very well made dust collector, and when I bought mine it was also moved the most air. Still, remember it lacks the airflow for good fine dust collection so I only use mine when I can wear my 3M 7500 NIOSH approved mask and can use a big exhaust fan blowing outside, otherwise I use my cyclone. Your comment regarding small home cyclones as chip collectors is one of the reasons I was getting confused from all the write ups. Almost all dust collectors 2 hp and under and all cyclones 3 hp and under lack ample airflow to power ducting, a seasoned filter, and still move ample air to our larger tools needed to meet the minimum OSHA air quality levels. I was concluding that the main advantage of the cyclone is that you would have less cleaning and more consistent airflow. Cyclones are far more convenient than the constant struggle with dust collector filter bags and constantly plugging cartridge filters, but a cyclone requires about one third more overhead than a dust collector to force the air into the tight separation spiral. They typically move about a third less air than a dust collector. That is why we need bigger cyclones to move the same air. It's encouraging to know that the trash can separators do a good job. A trashcan separator does a great job for “chip collection” but is near worthless for fine dust collection. Trashcan separators only work with airflows up to about 400 CFM as much more air volume simply scours the cans clean. To separate with larger airflows we need either a huge trashcan or a cyclone. Trash can separators and most unmodified cyclones provide near exactly the same roughly 85% separation by weight on typical dust meaning close to 100% of the fine dust is blown right through and into our filters. Most cyclones modified with air ramps and neutral vanes still only provide 80 to 85% separation by weight meaning most of the fine dust still ends up in the filters. Fine dust will quickly plug an undersized filter. As the filters plug the pressure goes up. With wood containing high amounts of silica better known as ground glass the increased pressure is enough to force these fine particles to cut and tear their way through our fine filters making for short filter lives. That is why I designed my own cyclone which provides better than 98% separation by weight with over 99.9% separation efficiency on dust sized 5-microns and larger before putting anything into the filters. This greatly reduces required filter sizes and extends filter life considerably. As a weekend warrior, 300 hours of operation could sadly take a year to hit. Agreed, but with the most dangerous dust invisible and something that builds in most shops, how do you know when you have a problem or when you need to change filters? I have the air filter so supplementing that with a 1100 CFM DC and trash can cyclone might do the trick especially if I exhaust outside. Again the trashcan separator will not work well with a 1.5 hp or larger dust collector unless you kill the airflow by using 4” ducting. Likewise, I agree exhausting outside plus wearing a good dual cartridge mask like the 3M 7500 series is a must. I also personally clean my shop regularly with a HEPA filtered vacuum to ensure it does not build up lots of dust that is easily stirred back into the air.

[Bill Leung]

Burt,

I'm in total agreement with you. As an mech engineer, looking at the cfm, micron, fps, data is always helpful in making the correct decision. The issue I was having with my research is that a lot of the information was conflicting. Some people say the bags just don't work. In practice more people said they did work then not but depends heavily on the environment and tools they are using.

So this is what I learned from this post which I hope will help others as well.

1) It appears that the higher CFM bags do work if they are maintained correctly or modified.

2) Dust hoods and shrouds are key to successful fine dust collection. It actually seems like if you improve this, you can also decrease your CFM requirement as you need more uumpf to catch the lighter faster dispersing fine dust.

3) Use a chip seperator.

4) Air cleaners are useful as fugitive dust is constantly in the air and being agitated.

As Bill Pentz knows, you can write a novel on this. I keep the list short for now. If others have comments to add please do.

[Bill Leung]

So, after all the great info from all of you I purchased a 20hp, .0001 micron, 4000 cfm, dual stage cyclone, with a lemon cented misting unit, and yes, it came with a kitchen sink. Seriously, I bought a Jet 1100 cfm 1.5 hp with Remote, set it up yesterday. I only got to turn it on for a bit but man does it suck... in a good way of course. I didn't get the chip seperator jet as I may not have the space for the extra can just yet. Where I have it placed in the shop, I will only need about 6ft or less of hose to reach the machine.

With the air cleaner, and the ability to open doors/window, I should be in good shape. I really do wish the DC had a kitchen sink though... that would have been helpful.;)

[Rick Moyer]

Bill, post back and let us know what you think after using it. I will eventually look at something similar I suppose, as I have a one person/ one-tool-at-a-time shop which I CAN open a 3-6' door on the end (but I don't like to in the winter, when I do most of my stuff). I think what you got would be adequate for me.

I do have a planer and jointer, though, so maybe not!? they do make a lot of messs without reasonable collection.

[Dave Lewis]

Bill:

I have Penn State 2HP cyclone and decided on the cyclone on part seeing the bag type collectors that typically leave a "puff " when they start.

Be advised that the duct-work / gates / hoses to stationary & portable equipment can cost almost as much as the cylone. Having said that, it sure it nice working w/o dust everywhere.

[Norm Koerner]

Too many people spend too much money on a cyclone to go with their dust collection systems. It doesnt have to be funnel shaped. For years I got by with a 55 gallon drum, cutting out the top, laying a piece of 3/4 plywood on it, pulling air out to the motor/impeller via a 6" hose centrally mounted in that "lid" and having the shop chips/dust enter the perimeter of the lid/barrel with an elbow inside to start the swirling action. In operation the suction holds the lid very tight even without rubber seal.

Then I found out a former student who is in the heating and A/C business with a "tin" shop could build me a true cyclone. For under $200 he will build you one, too. 6- or 7-inch inlet and whatever outlet size you want. Phone me at 217/787-8795 and I will pass on his number in south-central Illinois.

Another suggestion for y'all is to split your piping on the way back to the dust bags, running one branch to the exterior of the building. That way when you don't need to keep your heated air or cooled air returing to your shop room, you can blow everything outside, especially the fines.

To help eliminate noise, put the "guts" of your dust collector outside the shop, in an adjacent room, or in an enclosed area in the shop. If the later, insulate it well for sound dampening. Alot of the sound is emitted beyond the impeller blades, so think about putting a "muffler" there. It'll cut the noise in half. I got mine from Penn State. Under $100.

For smaller tools where a Shop-Vac might be sufficient.....like a sander, downdraft table, bandsaw, etc. consider a tiny cyclone. Oneida makes the Dust Deputy that fits on a 5-gallon bucket or 20-gallon drum and goes between between tool and Shop-Vac. Price is $99 for cyclone or about $160 with lid and container. 1-1/2 or 2-inch inlet and outlet.

Another nifty gadget to go with any Shop-Vac related hook-up with a tool is a self-actuating switch from Sears. You plug the unit in the outlet, then plug the tool and Shop-Vac into it. Firing up the tool turns on the Shop-Vac to collect debris and it continues to run 7 second after turning off the tool to clear the hose. Cost is $20. I also use in with lights dedicated to such tools as the bandsaw. The switch will self-actuate TWO tools simultaneously.