Why no cyclones?

[burn]

Over the past few months I've been reading in these forums about dust collection (DC) and clearly, some kind of cyclone or mini-cyclone dust collection system is much needed.

To be honest, I am a little daunted by building my own, but will evenutally have a go.

I'm curious, why isn't a mini-cyclone a mainstay product of the various suppliers dust collection sales. I note that Veritas has one, but all the rest seem to be geared towards the large company workshop - none for the home hobbiest?

Why? Surely there is a market for it. Perhaps Wayne needs to set up his own little company selling mini-cyclones ... might make a bundle! Roger Grifkins seems to be happy.

Perhaps some of the suppliers reading this might may comment.

Curiously yours

Burn

[DarrylF]

At the risk of getting into the whole cyclone debate again :)...

I can appreciate the benefits of having one, but almost all of those benefits can be had from a cartidge filter on top of a standard DC, for similar money in a smaller footprint. Sure you have to empty the DC bag itself more often, but you gotta empty the cyclone anyway, so what's the difference? The filtration is just as good with a cartridge. A cartridge on the DC will theoretically block more quickly at a given size, but I've never had a problem on that front.

It's probably cheaper to build a cyclone than to buy a cart filter, but not by a whole lot, and it certainly takes a bunch of time.

For my money the home shop cyclone became essentially redundant when DC cartridge filters became available.

[burn]

Thank you Darryl.

I thought I kept a close eye on the 'cyclone' and DC posts over the past few months, but didn't twig that the cyclone is basically a 'poor man's' cartridge filter.

[DarrylF]

Well kinda, but not really :) The fine dust will bypass the cyclone (stay airborne) and wind up in the DC anyway. With a standard bag on the DC it's still going to block just about as quickly, and the standard bag is still going to pass through the finest of it.

That's assuming you build (or buy) a cyclone that's an intermediate filter before the DC. All it's going to do is trap the heavier stuff.

If you build (or buy) a stand alone cyclone, it will have a smallish cartridge filter anyway to do the final filtering. They're physically larger than a standard DC + cart filter.

If you take a look at a cyclone and a standard DC, there's not actually a whole hell of a lot of difference between them anyway - they work on basically the same principle, spin the air to drop the larger particles out and filter the exhaust to trap the finer stuff. A cyclone simply has a larger cyclone chamber, with the resulting sacrifice of larger overall size.

If it 'aint broke, don't fix it. A standard DC with cart filter added works just fine.

[Grunt]

Yes, the Cyclone debate again.

A Cyclone will make your workshop Dust Collection System significantly more efficient and easier to manage.

Without a Cyclone your Filter will rapidly clog with large dust particles thereby reducing the airflow in your dust collection system. A reduced airflow means that less wood dust both large and small is being collected at the source. This wood dust then goes into your workshop atmosphere and then into your lungs.

A cyclone works by slowing the airflow in the cyclone which allows more of the airborne dust to fall into the primary dust collection bin leaving the filter to do its job on the small, dangerous particles.

A simple experiment to test this is to get a white sheet off your other half and hang it up outside on a windy day. Throw a handful of dirt into the air and see how much dirt gets on the sheet (your filter). Try the same on a day with a light breeze.

You will need to clean/replace your filter much less with a cyclone as the primary dust collection device. It is a lot easier to empty a bin full of large dust particles than it is to clean a filter full of large and small particles. Cleaning a filter that is full of the small dust particles is in itself hazardous to your health.

Sadly DarylF is right; cyclones take a lot of space.

IMHO if you are serious about shop safety and plan to do wood work with power tools for years to come then you need to have a cyclone as part of your Dust Collection System.

Have a look at Bill Pentz’s excellent web site on dust collection and cyclones.
http://cnets.net/~eclectic/woodworking/cyclone/index.cfm

Grunt

[burn]

OK, I can see that the best 'home woodworking shop' solution is

Dust Ducting => Cyclone => 2HP DC system with cartridge filters.

In catalogs I can see solutions of
Hafco's FC-10 + DC-3
Carbatec's CT-2042-P + CT-2042
Timbecon's Pleated Filter Bag + Carbatec's CT-2042.

BUT Hare&Forbes, Catbatec or Timbecon don't seem to sell cyclones.

OK, then perhaps I'm back to my original question. For those of us unsure about building a cyclone where to we get them from in Australia at home wood working prices.

[Grunt]

It actually goes

Ducting >> Cyclone with the 2hp motor ripped out of a DC >> Filter

Have a look at Wayne Davy's site. It shows the motor mounted on top of the cyclone. Wayne doesn't have a filter because he vents outsite because he either doesn't have any neighbours or he doesn't like the ones he has. http://members.optusnet.com.au/waynedavy/


I haven't built a cyclone yet as I'm just setting up my workshop. I too am a little daunted by the task of making one. The Bill Pentz web site has plans and I was going to take them to a sheet metal fabricator to see how much they would charge to knock one up. I would buy the 2HP DC from Carba-Tec or similar and let them mount it on the cyclone.

As far as the filter goes I don't think it is necessary to have one as big as the pleated filter bag. I read elsewhere on this BB that suggested that large truck air filters do the job. They'll be cheaper and not quite so big.

There is another post around that has a picture of a Cyclone with a smaller filter mounted inside a box.

If I find the links, I'll post them up to this thread.

[Wongo]

Just a quick question

I am thinking of getting a normal DC plus an air filtration system. Do you think it would be good enough?

Thanks

Scott

[Grunt]

This is a quote from Bill Pentz's Cyclone Site. As far as I can tell Bill is the font of all knowledge regarding Workshop dust.


Air Cleaners <br>
My respiratory doctor recommends installing a good quality ceiling mount air cleaner to help keep the shop air cleaner. He said the ceiling units are worthless for protection while you work, but they do help to clean up the air so every time you go back, you don't start with the same problems. I asked which one and he said that the magazines rated Jet, Delta, JDS, and Penn State all pretty close, but he bought a Jet for himself because he likes Jet tools. In looking at many woodworker posts and some magazine reviews, it appears that he did pick one of the best.

In following up I decided that if I caught the dust at its source and just let my cyclone run, an air cleaner would not be needed. An air engineer friend said that AAF had done extensive testing and found that was not accurate. An air cleaner is setup to stir the whole volume of air in a room. Without that stirring, much of the fine dust will be missed. Unless you setup your cyclone system so the air coming out of the filters blows in a directed stream at close to ceiling height, what happens is the air creates a narrow racetrack between whatever gate is open and the cyclone filters without doing a good job of cleaning the rest of the air. Moreover, a good air cleaner uses a small motor, meaning my dust collector would use more power and cost far more to run, plus is noisy.

[Wayne Davy]

Wongo,

Heed Grunt and Bill's advice - bag filters only get the big stuff which is just a pain to clean up. Its the invisible fine stuff that does you the physical damage.

So stats:
Bag Filters only get the 30 micron stuff - useless

Pleated Filters most only go down to 2 micron which is good but not the best

Proper "Torit" style filters are rated down to .5 micron but it depends on the model/brand.

Yes, I am direct venting but ONLY because I have an empty block next door. I DO intend to get a $280 Torit filter (sometime probably this year).

As for Air Filtration systems - only get one to keep your shop clean as they don't really do anything for your health. Think about this. You have a piece of wood and you cut/rout/sand it. The Air Filter is mounted above/behind you so the dust travels from the tool to you and you breath it in. You exhale and THEN the air filter gets it (possibly). Not good.

As Bill says, the only REALLY HEALTHY solution is a very, very efficient Cyclone and very, very good Hoods/Connections/Ducting to go with it so that nearly every single spec is picked up at the creation point (i.e. the tool). I have not quite achieved this yet but what I do have is working fairly well and my main problems are the ports/hoods on the tools which I am currently working on.

Anyway, if you do decide to start with a Bag D/C, get a 2hp at least and really consider a Pleated Filter as Darryl suggests.

[Wongo]

Thanks boys

[GeoffS]

Making a cyclone is not all that difficult. I'm no 'crash hot' sheet metal worker but a week of spare time achieved a working model to Bill Pentz's design.
If you can make useful furniture from wood you can make a cyclone from sheet metal. The only tools needed are a pair of good tin snips, a pop rivet gun and a beam compass. If you have not got them they are always useful so the money spent is not wasted. You can make the beam compass from your favourite material - wood. If you have curved snips all the better but not essential, if you have and can use soldering gear (big old fashioned plumber's gear) all the better but again not essential.
Well worth the effort and quite a few useful lessons in layout etc.
Cheers

[ndru]

The only tools needed are a pair of good tin snips, a pop rivet gun and a beam compass

If you've got a jigsaw already you can install a metal cutting blade to cut through the relatively thin sheet metal required to make a cyclone. (I haven't made a cyclone but have cut through sheet metal with a jigsaw). You may also be able to set up a circle cutting jig/compass for the jigsaw depending on the model of jigsaw.

If you use the jigsaw on sheet metal use ear protection!

Question for the cyclone makers - can you use tek screws instead of rivets?

[Wayne Davy]

I would not use Tek (or any other) Screws to ultimately hold the Cyclone metal together. The reason is that you will had lots of pointy sharp thing inside the Drum/Cone which will disturb the air/dust flow and potentially cause blockages. I did use some screws to hold it all together during construction but they were all replaced with pop rivets which were installed inside/out. ie. with the smooth/top side of the pop rivet on the inside of the Drum/Cone to ensure the air flow had minimal disturbances.

[dale]

Originally posted by GeoffS
If you have not got them they are always useful so the money spent is not wasted.


And by this statement we know he truly belongs in this forum :-)

[Sir Stinkalot]

Just to touch back on Burn's original question, which hasn't been answered yet .....

Quote:
"I'm curious, why isn't a mini-cyclone a mainstay product of the various suppliers dust collection sales."

Without going into the merits of cyclones vs. dust extractors (it seems as if the responses thus far have simply split one way or the other) ... why isn't there a commercially available home workshop sized cyclone?

From the grand old days of university studies I know that the cyclone principle is used to combat air pollution from smoke stacks and the likes, and we have all seen examples of large scale cyclones being used in factories. The only commercially available home scale cyclone that I have seen is "old dusty" at Carbatec in Melbourne .... Perhaps "old dusty" answers the question.

[Wayne Davy]

Good point Stinkie.

My take on why there are no "value" (cheap) commercial Cyclones (mini, mid or large) comes from several conversations with employees at Carbatec/Gregory Mach/etc. Basically, I was told they tried to sell "small" ones years ago but, as they were very expensive ($1K to $2K+), no one wanted them. Mostly came down to that woodies did know about the dangers of wood dust or just did not worry about it at the time. So, after trying it once, the Coys are not interested it offering them again.

However, times are a changing and we all seem to be getting more and more interested in Dust Collection systems. Usually starting with one just to keep the "Toy Room" clean and then getting more serious as we discover the dangers. This is happening big time in the USA and the US Coys are now offering "value" Cyclone systems to hobby woodies. I think this will happen here eventually, but dont hold your breath.

[silentC]

Makes me wonder if there isn't an opening there for an enterprising person with access to a sheetmetal shop to make these things and sell 'em on Ebay. As far as a piece of sheetmetal work goes, there's nothing to a cyclone. All you need then is a decent blower, a bin and some duct work.

Hmmm......

Do they have to be stainless steel, or could you make them out of gal?

[GeoffS]

And I wouldn't cut the metal we use in cyclones with a jig saw. It can be quite a light gauge - a pair of tin snips are not all that expensive. With the finest blade you wouldn't get 2 teeth across the thickness. I have used a jig saw for cutting sheet steel but it was 1.0 mm or more, for cyclones you can use 0.4 or 0.5 mm, maybe even 0.3mm.

Dale - if it is the funny English you are refering to - well you knew what I meant! or if it is the thought that you can NEVER have too many tools - well I certainly haven't found a limit

Cheers

[riffi1]

More info and links to member sites can be found in the Triton forum. One member has designed a minicyclone based on a Triton dustbucket and vacuum cleaner. It's on the list of things I'"gunner"build one day.

Rod:D

[Gumby]

Originally posted by riffi1
More info and links to member sites can be found in the Triton forum. One member has designed a minicyclone based on a Triton dustbucket and vacuum cleaner. It's on the list of things I'"gunner"build one day.

Rod:D

And I've seen it working first hand. It's abeauty and I've just been to the local paint store and picked up a 15L paint tin which the guy was going to put in the crusher. Now the weekend is booked....make my cyclone form the Triton bucket. :)