Thread: 1000 c f m

Why isn't it practical? Are industrial workers lungs less tough than home workers lungs? Confused!

(Unless I've totally misread your posting, in which case disregard))

I think about it all the time.

Why isn't there a simple solution? Why can't we buy a decently designed X-hp 6" cyclone with a pleated bag that doesn't cost the same as a good second hand car?

I've asked before, but we really should make an open-source plan that uses commodity parts, or engage a manufacturer to make them.

it is possible at a cost at this current time, the systems that are on sale at the moment in Australia are not capable of coming anywhere near the value. the other problem is were are being bombarded with USA standards that don't transcribe to Australian regulations or power supply/usage.
as I have said in another thread until local builders realize that there is a huge market in Australia and stop relying on American equipment and design for small duct work, not a thing will change.

my new blower is able to exceed that figure on the books. but it cost $1800 to build and its different to any of the designs that are out there. as it is experimental design im not aloud to release any details at the moment "Sorry non discloser doc" the man behind the design does have 15 years in air flow and dynamics engineering, and his father has over 40 years.

Originally Posted by Opelblues2

it is possible at a cost at this current time, the systems that are on sale at the moment in Australia are not capable of coming anywhere near the value. the other problem is were are being bombarded with USA standards that don't transcribe to Australian regulations or power supply/usage.
as I have said in another thread until local builders realize that there is a huge market in Australia and stop relying on American equipment and design for small duct work, not a thing will change.

my new blower is able to exceed that figure on the books. but it cost $1800 to build and its different to any of the designs that are out there. as it is experimental design im not aloud to release any details at the moment "Sorry non discloser doc" the man behind the design does have 15 years in air flow and dynamics engineering, and his father has over 40 years.

Can you at least give us an idea of scale? At $1800 I'm guessing it's still fairly small (home workshop with no more than 2 or 3 machines connected at once)

Also, many blowers can do it "on the books", whether it translates to results in the real world is another thing entirely. Not saying that your system is an "in theory only" design, just putting it out there.

I'll definitely be watching this thread.

the system is being created is/will/maybe for small home shops only, one operator, around the 40-50M3 area, using 150mm square or round ducting, at the combined distance of 35mt for all duct work, 3 machines plus floor pickup. "NOT USED AT THE SAME TIME" I'm not shouting but I do need to state it and to make it clear his for the record. I have put some money in to this but I'm not the designer. I'm only the voice of complaints.

with the commutations through emails and phone calls with different companies around Australia that make and design hi-end dust extraction systems. they use a simple and old design for their blower units and to this day there is no need for it to be changed. Now there are systems on the market that will do the 1000cfm, but they are large, nosier, very expensive, and need 3ph power.

No one that I have spoken to even the slightest considering small system for the home market

Well Barry, you know what I believe is 'practically' possible with a 2 or 3HP off the shelf single phase dust extractor. The 1,000 cfm figure is generally recognised as the minimum flow rate necessary to remove the fine dust that can damage your health. The figure was established by the 'God' of small shop dust extraction, Bill Pentz. I've never heard a negative word expressed about him so I think we can take it as a given that he is highly respected.

I don't believe you can achieve 1,000 cfm for any more than a few minutes with one of these off the shelf machines before the filters start to clog and the flow rate drops off. When I say 'drops off' I mean faster than the A$ in a GFC! And you'll only achieve the 1,000 cfm at all if you've modified the machine along the lines suggested by BobL in his exellent thread 'The Generic 2HP DC'. I don't believe there is a woodworker alive who would be prepared to clean his filter, bag or cartridge, every 10 minutes or less!

Unless you have the money to purchase and install a large 5 to 8HP dust extractor I think the best you can achieve will be delivered by locating the dust extractor outside your work area (many forum members cannot even achieve this!), optimising the extractor along the lines in the thread previously mentioned and installing a canister filter and a properly designed cyclone. 6" ducting is a given. You won't achieve the magic 1,000 cfm, but you will get the best result achievable within the constraints you have to work within, and on a far more consistent basis.

Yes I know, I sell a large cyclone suitable for the exact machines we are talking about, but the conclusion was what led me to seek out the cyclone, not the other way around.
Until we have a vastly superior machine available at a price we can afford the choices are pretty limited. I've often wondered why a dust extractor with a tip sealed fan is not available. The performance would be astronomically better. I'm too ignorant to help in this regard, but I would be surprised if there aren't others who could enlighten us?

Thats my 2 (maybe 10?) cents worth.

Possibly a dumb question, but what's a "tip sealed fan"?

In woodworking there's no such thing as a dumb question. I am possibly using the wrong terminology, what I mean is an impeller and housing where the blades move past a 'seal' that dramatically reduces the amount of backflow possible - to turn a fan in to a pump. Hope that helps. If not maybe it's the answer that is dumb and not the question?

Cheers,
David

Thanks, that makes sense.

Given the tight tolerances, I'd think a system like that would only work where the fan is located behind the filters and only has clean air passing through it. Having a fan like that on the "dirty" side would leave it at risk of being damaged or jammed by stray pieces of wood that get picked up.

Unfortunately, this rules out your generic 2-5hp units. Even cyclone systems usually have the fan before the filter; less risk of impact with the cyclone, but probably still possible.

Thank you for your responses.

As I am in South Australia I looked at Leda machinery for DC spec's, prices etc.

I found

SF-002T a bare bones machine, 8" inlet 2Hp single or 3 phase 2000 cfm

DC-2000 6" inlet 3Hp single or 3 phase 2200 cfm

CT-213 8" inlet 3Hp single or 3 phase 2500 cfm

I am aware there will be losses between the inlet and the various woodworking machinery.

I am hoping to reach that mystic magical figure.

As for losses on the output side, it's my opinion with my planned set up, (pat. pend.) ZERO or just above zero.

Many people have been called "idiots" in the past, yet when their theories are proved correct, they become "genius".

Let the debate continue...... I hope BobL shows up soon.

Cheers for now,, tomorrow its Mannum Men's Shed, guess whats on the agenda for discussion yes its DUST CONTROL.

Cheers Barry

Zero losses on the output side, to my mind, would mean zero restrictions after the fan.

As far as I can tell, there are 3 ways of doing this:
1) Filters before the fan (you still have your regular losses from filters, but it's before the fan so, technically speaking, zero loss on the output side)
2) ULTRA effective cyclone with no filters (Bad idea. I don't care how effective a cyclone is, it's not going to get everything)
3) Dark magic (This is frowned upon in the wider community and is generally considered to be a bad idea)

If my initial definition is wrong, please correct me and disregard everything I just wrote.

Originally Posted by aldav

In woodworking there's no such thing as a dumb question. I am possibly using the wrong terminology, what I mean is an impeller and housing where the blades move past a 'seal' that dramatically reduces the amount of backflow possible - to turn a fan in to a pump. Hope that helps. If not maybe it's the answer that is dumb and not the question?

Cheers,
David

The big problem with a housing that might have any sort of seal is it would make an horrendous amount of noise, if you want to make an air raid siren just place a "seal" close to a rapidly rotating fan wheel blade, the woodgears guy made an air raid siren, might be worth a look if you want to see what I mean.


Pete

Originally Posted by elanjacobs

Zero losses on the output side, to my mind, would mean zero restrictions after the fan.

As far as I can tell, there are 3 ways of doing this:
1) Filters before the fan (you still have your regular losses from filters, but it's before the fan so, technically speaking, zero loss on the output side)
2) ULTRA effective cyclone with no filters (Bad idea. I don't care how effective a cyclone is, it's not going to get everything)
3) Dark magic (This is frowned upon in the wider community and is generally considered to be a bad idea)

If my initial definition is wrong, please correct me and disregard everything I just wrote.

Come on woodies, termites, scholars,.........think obout it.

No special filters, No dark magic, just plain simple natural no filters at all.

I have posted questions to BobL over a few months exploring "my way" that may give you a clue.

Cheers Barry

Originally Posted by pjt

The big problem with a housing that might have any sort of seal is it would make an horrendous amount of noise, if you want to make an air raid siren just place a "seal" close to a rapidly rotating fan wheel blade, the woodgears guy made an air raid siren, might be worth a look if you want to see what I mean.


Pete

Hmm, I hadn't even considered the possible noise problem. Was more concerned about the possible extra horsepower required to drive it. I did warn you all I am ignorant, didn't I? I did expect a change like that to involve a complete re-engineering of what is currently on offer though. But, it's amazing what can be achieved when a good engineering brain turns itself to the task of solving a problem on a subject they are passionate about.

"No special filters, No dark magic, just plain simple natural no filters at all." mannum3

Like Elan, I've never been a fan of no filters and don't think it is a viable option for most woodies. That said, if you can get away with it go for your life. I agree it is probably the only way you have a hope of achieving a consistent 1,000 cfm with any of these machines.

Suspect BobL is keeping his powder dry and will explode on the scene with some figures and information that will make some of us look like knuckleheads.

Speaking of knuckleheads, how do you get multiple quotes in the one reply?