Dust Collector vs. Cyclone

[Chuck Harris]

Getting curious about the value of a cyclone vs. a bag dust collector. I currently have a 1.5hp Shop Fox Dust collector in my shop. I have built in pipe to the lathe station and am planning to modify the piping to have solid metal or PVC pipe to improve effeciancy. Multiple ports to shorten the flex hose runs to the machines. The TS, Jointer, Shaper, Bandsaw, and planer are all mobile. I am also planning to change the way the collection is at the lathe station to improve chip collection. Do the cyclones have more collection power than a similar hp CFM bag system? how are they on noise? In short guys whats the difference?

[Steve Cox]

Cyclones have several advantages over bags. One, the filter media is usually much finer than any bag. This means that the air returned to the shop is cleaner than the air from a bag unit. It is the most harmful size particles that are better removed by a cyclone. While a bag system with clean bags may equal a cyclone in suction, as the bags get clogged (and they will very quickly) the resistance will create a back pressure in the system which prevents the bag system from performing to its' peak. So, in essence, a cyclone has more suction. In addition, since the large chunks are removed before the air gets to the filter, the filter stays cleaner much, much, longer than with a bag system. I have taken numerous cans of waste from the bottom of my cyclone and have had no need to clean the filter. With my old Jet bag system the inside of the closet where it resided was caked with dust. With my Woodsucker cyclone there is none. It is well worth the upgrade.

[Dale Thompson]

Chuck,
From a purely engineering standpoint, a "cyclone" is the LEAST efficient way of removing dust from a "dirty" air flow media. A bag collector is far better and a "scrubber" is better yet.

A "cyclone" depends on cyclonic (spinning) flow to separate the "coarse" materials from the "fines" as a result of centrifugal forces. The "fines" are NOT subject to these forces and, therefore, must be handled elsewhere such as in a filter or being exhausted to the atmosphere. A bag collector filters to the micron level for which it is designed. As the bag becomes clogged, the efficiency of the overall system decreases but the micron size of the collected material decreases (ie. gets better).

With that said, the WWing suppliers who are heralding "cyclones" are, in fact, selling first stage cyclones and second stage bag (filter) collectors. They have an excellent product but they are "technically challenged" in terms of marketing.

I've got a bag collector in my shop. However, if I had the need, I would not hesitate to "upgrade" to a cyclone ---- assuming the micron ratings of the filter were superior to my bag.

I'm confused? :confused: Is a "cyclone" a tornado, a hurricane or just a revolving atmospheric phenomenon? :( DAH???? Youse guys make yer own decisions! :cool: ;)

Dale T.

[Steve Cox]

A tornado is a "...a violently whirling column of air extending downward from a cumlonimbus cloud...". A cyclone is "...a storm with strong winds rotating about a moving center of low pressure.". And a hurricane is "...a violent tropical cyclone with winds moving at 73 or more miles an hour...and originating usually in the West Indian region..". At least that's what my Websters tells me.:p Anyway, all I know is that my Woodsucker works much better than my Jet DC-1200.:) BTW you're welcome Dale.;)

[Jerry Clark]

Dale, he cheated-- he looked it up!;)

[Andy London]

I don't profess to be an expert on dust collection, I simply know what I have experienced in my own shop. I started with a shop vac years ago, bought a dust collector when they first came on the market, wasn't impressed with the fine dust, upgranded the bags, then upgraded to a 2 h.p. unit, upgraded the bags and have now upgraded to a cyclone. Below is a page with an overview.

http://www.picframer.ca/cyclone.htm

The biggest difference I have seen is the cyclone seperates most of the dust from the air, meaning the air going to the filter takes a lot longer to load the filter before I had to clean it in order to maintain a required CFM. With the 2 h.p. unit, I had to clean out the upper bag once, sometimes twice a week to maintain a decent CFM at the tools, if my son was turning during this period, I would have to clean it almost daily...in short it was a pain and cleaning these filters is not a realy healthy idea as dust goes everywhere even when done outside which I always did and it's super fine.

I cleaned the filter in the cyclone after 6 or 8 drums of dust collectoin and received less than a teaspoon, I was pretty impressed.

I have now emptied well over 50 drums of dust from the drum and have not touched the filter as the CFM at the tools is still very, very high. My son has spent at least 60 hours at the lathe sanding which would have killed the bag unit with loading.

So in short, in my experience, it's simply more efficient and the air quality in the shop is night and day as I leave the cyclone running most of the time as it's no lounder than a tablesaw, perhaps less.

Andy

[lou sansone]

I agree with andy
here is my two cents worth


1. cyclones offer another some advantages for some installations and some types of shops. I have had both bag and cyclone systems and like the cyclone way over the bag only system.
If you are really producing a lot of chips from planning opperations then the cyclone is really nice because of the large collection possibility. I use a 55 gal drum and there have been times when I have emptied it at least 3 times per day.
2. My system is two part with the cyclone on the outside of the shop and the return air and filter media inside. I find it much easier and a lot less messy to empty the chip drum outside rather than inside my shop, especially when I am running my wide belt sander a lot.
3. I also like the split system because I don't take up valuable shop space with the cyclone and dust barrel inside, that would be hard with the bag system.

lou

[Jim Dannels]

I have considered both, and find myself in a quandry.

It seems to me that if the purpose is to stop fine dust you can inhale, emptying bags would put you directly in the stream for inhaling the fine dust you are trying to elminate.

I am convinced that the cyclone is the way to go, however, I like the canister machines that deposit the dust and chips in a plastic bag you can seal and dispose of.

It seems to me that ideal would be a hybird system that combines features of the cyclone. canister & bag would be safest and most efficent?

I am not sure any hobbiest directed system is built that does all this?

[Jim O'Dell]

I have considered both, and find myself in a quandry.


It seems to me that ideal would be a hybird system that combines features of the cyclone. canister & bag would be safest and most efficent?

I am not sure any hobbiest directed system is built that does all this?

Does anyone know if there is a way to line the chip barrell with a plastic bag so that one could pull it out of the barrell after tying it off to keep the dust level down? Jim.

[Dan Lyman]

Oneida just came out with this. I don't know how well it works, but it sounds good.

http://synergy.oneida-air.com/public/docs/BDDocument.asp?Action=View&ID=%7B3B13F15A-EEC9-41DA-BECD-DB25E4CDEEEE%7D

[George Matthews]

I have considered both, and find myself in a quandry.

_snip_
It seems to me that ideal would be a hybird system that combines features of the cyclone. canister & bag would be safest and most efficent?

I am not sure any hobbiest directed system is built that does all this?

If you use a good N95 dust mask, that takes care of the 'health' aspects no matter what chip/dust collection system you use and how/where you empty/clean the collection bag/bin.

A mask plus any or no DC is also far less costly than a maskless system as far as I have experienced with my bag collector. Most masks are close to useless, but a good face seal and exhaust/exhale ports make it far more tollerable :rolleyes:

[Jim Becker]

I would only consider using the Synergy bag system if I was largely collecting fine dust from sanders and small tools. I compost the chips and dust as it is, so I just put the barrel in my tractor's loader and cart it accross the property. Very little dust is stirred up when I'm moving the barrel out of the DC closet to it's waiting transport...

[lou sansone]

I would only consider using the Synergy bag system if I was largely collecting fine dust from sanders and small tools. I compost the chips and dust as it is, so I just put the barrel in my tractor's loader and cart it accross the property. Very little dust is stirred up when I'm moving the barrel out of the DC closet to it's waiting transport...

That is a nice way to do it, and I agree that the dust is kept to a minimum. If you have to put it into bags to take to the dump and road side PU then you do have a mess on your hands.

lou

[Dale Thompson]

A tornado is a "...a violently whirling column of air extending downward from a cumlonimbus cloud...". A cyclone is "...a storm with strong winds rotating about a moving center of low pressure.". And a hurricane is "...a violent tropical cyclone with winds moving at 73 or more miles an hour...and originating usually in the West Indian region..". At least that's what my Websters tells me.:p Anyway, all I know is that my Woodsucker works much better than my Jet DC-1200.:) BTW you're welcome Dale.;)

Thanks Steve,
Your definitions tell me that a tornado, twister, etc., and a hurricane are all cyclones. :)

My point was that the marketers of the "cyclones" in our WWing world are technically underselling their excellent products from a purely engineering standpoint. ;)

By the way, I envy you guys who empty your "systems" on a daily or even a weekly basis. I empty mine about every three months. That's because 90% of my shop time is spent in the "Emergency Room" of our local hospital. :eek: It's a GREAT way to meet pretty young nurses but they are all looking for rich guys who are under ninety years old. :( OK - two strikes and I'm OUT!! :o :cool:

Dale T.

[Michael Perata]

Does anyone know if there is a way to line the chip barrell with a plastic bag so that one could pull it out of the barrell after tying it off to keep the dust level down? Jim.

I have heard of people finding wire style baskets that will fit somewhat tightly into the drum to hold contractor type bags from flying back into the cyclone for the dust. I'll be trying this as I have a big milling job coming up and I foresee many drums full of dust/chips.

[Sam Chambers]

Does anyone know if there is a way to line the chip barrell with a plastic bag so that one could pull it out of the barrell after tying it off to keep the dust level down?

Jim:

Penn State sells something called a "VAC SAC" that fits inside the disposable plastic bag to keep it from being sucked into the motor. There's nothing showing up on their web site for it right now, so I don't know if they still carry it. I had been thinking about doing something similar, like using a piece of Formica cut so it would fit snugly inside the trash can, with duct tape wrapped around the edges to keep the bag from tearing.

[markus shaffer]

I cut a piece of formica laminate to fit on the inside of my cyclone barrel. Put in a bag and then roll up the laminate to fit inside. The outward pressure keeps the bag tight against the barrel. I rounded off the corners so that it doesn't puncture the bag when I pull it out. Roll it up in opposite directions every few times ensures that the laminate will not form to one direction. It's a little bit of a pain to pull it out sometimes when the barrel is packed really tight with fine dust, but with regular chips from the planer it's no problem to pull out. It does make for emptying the barrel a bit nicer than trying to dump the contents into a bag.

-Markus

[Jack Wood]

Has anyone else noticed that dust collection is one of the hottest posted to topics on the mill? It amazes me with the degree of technical knowledge that some of our members have in matters such as these. If you want to fire up the posting just ask for opinions on DC'ing and stand back!:D I for one have a 2 horse from HF($130 on sale:D ) and a single 20'- 5" hose($50) assorted connectors,($50) that I move around to my various machines. I have a small shop, 20x24 and am not into production work so to move it around is no problem. I then have the bag collector on the outside of my shop so no secondary blowby dust is created by it. If you can vent the pipe to the outside it really is not going to make sense to buy a really expensive system when for about $250 you can do the same thing. But not everyone can vent outside so there's where the more complicated types come in. So theres my 2 cents worth:D THE MILL ROCKS!