Thread: the new cylone

Also remember that two years ago I bought a Triton dust bucket and then looked at 'Peter the Jigs' modification to make it into a 'Mini Cyclone' followed by making a dual mini cyclone and many other dust reducing options(buckets etsc) It was you Australians' that got me on to this cyclone thing . I have had so much fun building these 'cyclones'
Thanks again
Barry

Have you done any more to your cyclone Ironwood?

hi all, Ive been in brisbane, laaid up in hospital for the last week, have escaped to lobby and found a computer to check up on whats going on. will be back home soon hopefully and back doing things. wont have time now to add too mmuch.
Ironwood>

Originally Posted by ironwood

hi all, Ive been in brisbane, laaid up in hospital for the last week,

Sorry to hear your in hospital Brad, wish you a speedy recovery.

Well that sucks............. the hospital, not the cyclone, this time...

Get well soon!

Ironwood - I hope you are up and about soon and back to your cyclone. Don't want you getting cyclone withdrawal symptoms
Barry

Originally Posted by BarryBurgess

Ironwood the Pentz site suggests that if you reduce the diameter of the chamber it will work better with smaller motors. Their motors also run at 3400RPM verses 2850RPM with 220/240 volt. ...
Barry

Oops.. just a little caution here. The smaller the cyclone diameter and chamber the bigger the motor and impeller required. The tighter the separation spiral you force the air to go into, the more power it takes. The ideal cyclone diameter for 4000 FPM and 800 CFM is a 13.5" cylinder but need a big motor and impeller. We should go up from there, but the hobbyist vendors realized they can skate by using smaller motors and give up some separation efficiency.

Although using the smaller motors is not best for separation efficiency, many of us have no choice. So my rule of thumb for 3450 RPM motors is build 1.5 hp cyclones with at least 22" diameter cyclones, 2 hp with at least 20" diameter cyclones, 3 hp with at least 18" diameter, and 5 hp with at least 13.5" diameter cyclones. Going smaller ends up causing plugs. Figure a 12.25" impeller for 1.5 hp, 13" for 2 hp, 14" for 3 hp, 15" for 4 hp, and 16" for 5 hp for powering a cyclone. With your 2850 RPM motors versus our 3450 RPM, you can step up one impeller size across the board.

bill

Bill,

One possible problem facing guys out here is the potential difficulty in obtaining individual components, hence the preference to "butcher" existing DC units for the motor and impeller, so "jumping up a size" is not necessarily an option.

When using your site for reference we then are faced with the approx., 17% reduction in RPM (due to power supply differences) which further confuses the issues.

Speaking for myself, I'm still trying to figure out how I can get the best performance out of my 2hp, 13" impeller combination which runs at 2850rpm (I have been visiting your site for close to 18 months and I'm as confused as ever ). I do have the option of seperating the impeller and motor and then, with V-belt/pulleys, gearing the impeller RPM up a tad but regardless of which way I go there, I'm still unsure of cyclone and duct sizing for optimum performance.

Cheers

Bill as HiString says its nearly impossilbe to get the seperate bits and far cheaper to butcher a dust extractor. In the UK the biggest impellor is 13.5" and 3HP motors is the largest I can find using a single phase at a reasonable cost. With these limitations and not being a metal worker I had to find a ready made cone ( flower pot from a store called Ikea) and this led to a 15" diameter cyclone.
It certainly works and I am getting no visible dust into the filter. This is my effort having spent too many hours reading your site and not getting down to building one.
http://burgess.barry.googlepages.com/Cyclonebaffle.jpg

The baffle makes a big difference with the noise.
Thanks again
Barry

Tucked my two cents into your posts in blue.

Originally Posted by HiString

Bill,

One possible problem facing guys out here is the potential difficulty in obtaining individual components, hence the preference to "butcher" existing DC units for the motor and impeller, so "jumping up a size" is not necessarily an option. We had exactly the same problem here, no available affordable impellers, when I started this back before the turn of the century. What I ended up doing was searching all over for a blower firm willing to sell to hobbyists who would make a good solid impeller with a compression arbor. I convinced Sheldon’s Engineering in Canada to help and we did well making them a few dollars and taking care of many hobbyists until that firm was sold and the new management decided that was not an area they wanted, so raised prices considerably. I suspect you are going to have to do something similar and find a firm or machinist like I did with Ed Morgano who now owns and runs Clear Vue who will turn out similar impellers.

When using your site for reference we then are faced with the approx., 17% reduction in RPM (due to power supply differences) which further confuses the issues. I’ve been through the engineering enough times helping people that live at high altitudes that I would be happy to help whatever firm or machinist you find to appropriately size these units to work with your available motor sizes. Just let me know.

Speaking for myself, I'm still trying to figure out how I can get the best performance out of my 2hp, 13" impeller combination which runs at 2850rpm (I have been visiting your site for close to 18 months and I'm as confused as ever ). For that I truly apologize as my site started as a whole bunch of separate articles that got smashed together into the same web pages, and have slowly been going through rewrites to take out some of the superfluous, redundant, and duplicative information. I do have the option of separating the impeller and motor and then, with V-belt/pulleys, gearing the impeller RPM up a tad That is the correct solution and the best way to go is use a variable pulley then adjust speed until you are at about 95% of your motor’s rated amperage.but regardless of which way I go there, I'm still unsure of cyclone and duct sizing for optimum performance. The amount of air you move is directly related to horsepower. Your 2 hp motor will comfortably move 1200 CFM but you have to adjust impeller speed or size to get there.

The rule of thumb is a ¾ hp motor will move the 550 CFM which is better than the 350 CFM that we need for good “chip collection”, meaning getting the same stuff that otherwise gets swept off the floor. A 1 hp motor will support about 800 CFM which does a little better job of “chip collection”. A 1.5 hp motor will move about 1100 CFM. A 2 hp motor will support 1200 CFM, a 3 hp about 1400, and a 5 hp about 1800 CFM. If you only ran one machine, could set your dust collector right next to that machine and used big ducting, these are all real values that would work. What you would have to do is either adjust impeller sizes or use a variable speed motor/pulley to push the amps right up to the motor limit and you would get this airflow.

The rule of thumb to keep our ducting vertical runs from plugging is to use 4” to support 350 CFM, 5” ducting to support 550 CFM, 6” to support 800 CFM, and 7” to support 1000 CFM. So if you can keep your airflow up at maximum your 2 hp will clearly support 7” ducting. Unfortunately, airflow drops as we add the overhead of our ducting, filters, cyclone, filter plugging, etc. which is why we estimate worst case resistance then use a fan table to see what kind of air our blower will move in a worst case situation. You can use my Static Calculator to get a pretty good estimate of the resistance level, but for most with a typical 2-car garage sized shop here, that resistance works out to about 8.11” on the high side. On the low side we end up with about 1.7”. That leaves us tuning performance by either adjusting impeller size or speed to max the motor amperage at 1.7” and get a big enough motor to still drive at least 800 CFM and preferably 1000 CFM at our worst case.

If you work through the physics this means we really need about a 3.11 hp motor minimum. The fan tables confirm this to be the case. At the same time we can get by using a 2 hp and putting all our high airflow demand tools right next to our cyclone with 7” ducting going to each. We would then go to the distant machines with nothing less than 6” duct.

Whew.. a long winded way to say put your cyclone and big tools together connected by 7” ducting and adjust impeller speed so that the least resistance does not exceed your motor amperage. Then duct the rest with 6” and be happy. Otherwise, get a bigger motor and you gain the flexibility of being able to put your tools in your shop where you want and still get good fine dust collection.

Cheers

Originally Posted by BarryBurgess

Bill as HiString says its nearly impossible to get the separate bits and far cheaper to butcher a dust extractor. In the UK the biggest impellor is 13.5" and 3HP motors is the largest I can find using a single phase at a reasonable cost. With these limitations and not being a metal worker I had to find a ready made cone (flower pot from a store called Ikea) and this led to a 15" diameter cyclone. Again we had the same problem here and my solution was to talk a firm into supplying what was needed and made it worth their trouble by getting them lots of customers. As an aside Ikea opened a store locally a few months ago. I’m way too slow to make what they want, so my wife and daughter want to bankrupt us with Ikea stuff. We put together my daughter’s room at college with all new Ikea, got drafting and craft stuff for my wife, and now looking at setting up a room for my son who will soon be leaving home for college.
It certainly works and I am getting no visible dust into the filter. This is my effort having spent too many hours reading your site and not getting down to building one.
http://burgess.barry.googlepages.com/Cyclonebaffle.jpg I like what you did and your efforts go to show the huge benefit of using a cyclone separator to help with the wood dust mess. I really do think you would be very pleasantly surprised at how much better building one of my design would help in your shop.

The baffle makes a big difference with the noise. Also consider wrapping the outside of your blower in insulation or foam, using an insulated duct coming out of the blower, a foam pad between the blower and cyclone, and a flex hose between cyclone and ducting to reduce noise transmission. These changes with muffler cut my noise from 94 dB to under 80 dB.
Thanks again. Actually I want to personally thank you. Many people have written that you have gone well out of your way to post some great advice and frequently steer people to my web pages.
Barry

Barry & HiString,

The other thing I wanted to share is more on this sizing the cyclone issue. I really hope I did not put you off with what I said, as that was not my intent. Just because using a bigger cyclone allows a smaller motor and is what most vendors do, it is not a very good solution. Just as Barry said and shows with his cyclone, going smaller provides far better separation. This holds true for wood dust until you get down to about 13.5” inches in diameter, then we get plugging issues from the chips and small clearances.

Just for a little more confirmation, take a look at the new Clear Vue 1400 cyclone I designed last year and just went to market. It is built on a 13.5” diameter cyclone as this gives the best separation in the smallest package, but at a cost of some reduced airflow and my having to bump to a 16” impeller turning at 3450 RPM. This big impeller is needed to drive that smaller diameter cyclone, but the result is so much faster airspeed we get far better dust pickup. Also this pressure is so high this cyclone can move a real 800 CFM through the smaller 4” duct even if not recommended. It will also flatten cheap 6” HVAC 30-gauge duct if we are foolish enough close all the gates at once.

Anyhow, my best to you on this forum because most of you roll up your sleeves and really do instead of the incessant arguing that I constantly see here. Dicky Forde, one of my long lost buds from high school woodshop classes decided the same and went there decades ago and never came back. You need to watch that you know? Soon you will have a reputation for stealing woodworkers like our state of Texas does for stealing pretty girls. They go there to visit and never come home. I know because that state got two of my sisters.

bill

Hey Bill, nice to see you out and about over here too!!

I really have to say that the design I used to make my cyclone (a Pentz design of course) really does work.

I too need to up my impeller speed, but finding a shaft, some pulleys and such is not an easy task here, I'm sure it would make my system even better than it is (hard to imagine really).

Cheers!

Hi all ,
I'm back at home at last !!. not up to doing anything strenuous yet, but i'm doing plenty of thinking, planning and dreaming . managed to pick up a few old tools at a dealer in Wooloongabba, not far from where i was staying after i got out of hostpital, which didnt fail to chear me up .

Hi Bill,
I was pleasantly surprised to see your replies on the active cyclone threads, I am sure your advise will benifit and inspire us all, especially those that havent taken the plunge and started their cyclones yet (I think it wont take long before they start building)

Originally Posted by Stu in Tokyo

I too need to up my impeller speed, but finding a shaft, some pulleys and such is not an easy task here, I'm sure it would make my system even better than it is (hard to imagine really).

Cheers!

Hi Stu,
I'm thinking this may be the road I go down also, after reading the replies while I have been away. though i still have a bit to do with the ducting to my machinary before i can judge how effective my system is with the cyclone upgrade.
As I still have a fair bit of amperage to play with, before i get anywhere near my motors rated amp draw, I am thinking it wouldnt hurt to load it up a bit, speeding up the impellor sounds like the way to go

Originally Posted by Ironwood

Hi all ,
I'm back at home at last !!. not up to doing anything strenuous yet, but i'm doing plenty of thinking, planning and dreaming . managed to pick up a few old tools at a dealer in Wooloongabba, not far from where i was staying after i got out of hostpital, which didnt fail to chear me up .

Welcome back Brad hope you have a speedy recovery and are back into action again soon.