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Thread: Does A Blowers CFM Rating Change When Converting to A Cyclone Setup?

  1. #1
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    Does A Blowers CFM Rating Change When Converting to A Cyclone Setup?

    I have a 2HP. 3PH. blower/motor from an old Cincinati Dust Master 2-stage 55gal. barrel style dust collector that I plan to use for a cyclone setup.
    The factory specks for the original dust collector are 1100-CFM. Here's the data sheet on the original dust collector, my model is the 200S https://www.cincinnatifan.com/catalo...ors108-sls.pdf

    I'll be adding a cartridge filter for the exhaust so the resistance will be reduced quite a bit, the original filter bag only had 18sq. ft. of surface area & the cartage filter has over 300 sq. ft. of surface area!
    Will the reduced air resistance also increase the CFM rating of the blower?

    Doug

  2. #2
    The 1100 cfm figure is at 0" static pressure with the stock filter in place and 5' of inlet hose. Flow figures are meaningless without an associated static pressure. The new filter will help with airflow (unless/until it gets clogged), the cyclone will diminish it. The cyclone, if designed and installed properly, should keep most of the fines out of the filter.

    Here is some info that may be helpful https://airhand.com/dustcollectioninfo/

  3. #3
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    The impeller says it is 12 1/4 " , with a 2 HP blower on a Dust Deputy should give pretty good CFM , not super . Don't ask it to do too much , like service elaborate , long branches and it will be OK . I've got a 2 HP Grizzly w/ a 12 3/4 " impeller on a shop built cyclone that works well in my small shop . An impeller upgrade might help . Look at the height as well as the diameter of the stock impeller . The Cincinati blower housing is not as wide/ thick as some newer blowers out there , so a larger impeller might not be feasible . I think the DD is probably as good as any in terms of resistance , but expectations need to be realistic .

  4. #4
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    Quote Originally Posted by Kevin Jenness View Post
    Flow figures are meaningless without an associated static pressure.

    The new filter will help with airflow (unless/until it gets clogged), the cyclone will diminish it.
    So basically, it's kind of a give & take between the two?

    Doug

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    Quote Originally Posted by Doug Walls View Post
    So basically, it's kind of a give & take between the two?

    Doug
    Yes. It will be something like 1100 cfm at 0"wc and 0 cfm at 15"wc.

  6. #6
    Quote Originally Posted by Doug Walls View Post
    So basically, it's kind of a give & take between the two?

    Doug
    Yes. The cyclone will add resistance to the system but the cartridge filter will offer less resistance when clean.

  7. #7
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    Quote Originally Posted by james manutes View Post
    with a 2 HP blower on a Dust Deputy should give pretty good CFM
    I've looked at the specks for the steel version of the Super Dust Deputy & they recommend a blower range from 0-5~3hp, so my 2hp blower should be good. The only thing with the Dust Deputys is they all have a right-hand outlet, And I should use a left-hand outlet.
    Steel Dust Deputy .jpg

    Quote Originally Posted by james manutes View Post
    Don't ask it to do too much, like service elaborate, long branches and it will be OK.
    I'll just be using it for a couple of machines & only one at a time, probably about an 8 foot main run with three 4" drops.

    Quote Originally Posted by james manutes View Post
    An impeller upgrade might help. Look at the height as well as the diameter of the stock impeller. The Cincinati blower housing is not as wide/ thick as some newer blowers out there, so a larger impeller might not be feasible.
    Yeah, the Cincinnati blowers have more of a rounded/curved housing & from what I've read the impeller is matched to the housing.
    IMG_4732.JPGIMG_4770.JPG
    The impeller is made from a thick aluminum casting & it's machined on the back side to balance it.
    IMG_4775.JPGIMG_4777.JPG

    Doug
    Last edited by Doug Walls; 05-14-2022 at 10:14 PM. Reason: Picture Update

  8. #8
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    As long as the HP is adequate to turn the impeller at full speed the HP is not the important factor, the impeller size is. If a 13" impeller is driven by a 3HP motor or a 5HP motor both at full speed the air flow will be the same and 12.5" is way too small for system to pick up fine dust in my view but others may disagree. Driven by a 3 phase motor and a VFD it will be marginally better but not by a lot. I think 14" is minimum with 15" being ideal and that has a long history of being able to give good air flow. Any cyclone of whatever brand introduced into a DE system reduces air flow because their inefficiency is how they work.
    Chris

    Everything I like is either illegal, immoral or fattening

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    Quote Originally Posted by Doug Walls View Post
    I've looked at the specks for the steel version of the Super Dust Deputy & they recommend a blower range from 0-5~3hp, so my 2hp blower should be good. The only thing with the Dust Deputys is they all have a right-hand outlet, And I should use a left-hand outlet.
    I believe that is the inlet.

    My point of comparison: I had a Jet DC1100 (1-1/2hp with canister filter). This worked okay for collecting some of the heavier sawdust (although tablesaw and bandsaw still had noticeable dust escape). Jointer/planer dust collection more effective, although I was having trouble with light shavings floating in the DC and packing the filter, rather than settling into the collection bin. I added an oneida super dust deputy (resin, 5" inlet, 6" outlet), which worked great for separation.

    Do make sure your collection drum is reasonably matched to your work -- I had the small (17gallon) metal drum, which looked nice but which filled pretty quick when milling. This was noted when seeing some shavings heading into the DC proper, which meant the cyclone was already packed.

    Matt

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    Quote Originally Posted by Matthew Hills View Post
    I believe that is the inlet.

    My point of comparison: I had a Jet DC1100 (1-1/2hp with canister filter).

    Matt
    With no disrespect to Matt his post illustrates my point regarding how we look at sizing dust extractors. In the great big scheme of things 1-1/2HP tells us very little about the flow capacity because we don't know the impeller size apart from it must be on the lower end of the size scale. If he had specified a 12" impeller then we would have an instant understanding of the capacity of his system and can judge his system against what may work for others. It is not unknown that the same size impeller can be used in two different HP ratings and they both operate at the same speed with no flow difference between them. The main problem citing impeller size is that most of us have no clue what it is because the information is not included in the sakes blurb so the headline HP figure has become the default figure used when discussing dust extraction.
    Chris

    Everything I like is either illegal, immoral or fattening

  11. #11
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    Quote Originally Posted by Chris Parks View Post
    With no disrespect to Matt his post illustrates my point regarding how we look at sizing dust extractors. In the great big scheme of things 1-1/2HP tells us very little about the flow capacity because we don't know the impeller size apart from it must be on the lower end of the size scale.
    These are all good points.

    I believe the DC had an 11" impeller.
    And you're right that these aren't marketed in a particularly helpful way.

    The cyclone did help with one problem (clogging filter that was confounding effective chip collection) without appreciably affecting standard sawdust collection. However, I wasn't satisfied with the fine dust collection from that system with the tools I was using.

    Matt

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    Upsizing an impeller can be hard sometimes . You might find the larger one you want , only to find it needs a 7/8" shaft and you have 3/4" . The height could be 95 mm , your blower housing handles 85 mm max. Grizzly has an assortment of impellers across their product line , usually in stock . Having now built 4 "cyclone DC's " , I can only offer that you can save some $$ , but you won't have a CV 1800 when you're done . You can see improvement w/ your DC situation , as any 2-stage that's not a short cone is likely an upgrade in itself . Have realistic expectations , and enjoy the build process .

  13. #13
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    Quote Originally Posted by james manutes View Post
    Upsizing an impeller can be hard sometimes . You might find the larger one you want , only to find it needs a 7/8" shaft and you have 3/4" . The height could be 95 mm , your blower housing handles 85 mm max. Grizzly has an assortment of impellers across their product line , usually in stock . Having now built 4 "cyclone DC's " , I can only offer that you can save some $$ , but you won't have a CV 1800 when you're done . You can see improvement w/ your DC situation , as any 2-stage that's not a short cone is likely an upgrade in itself . Have realistic expectations , and enjoy the build process .
    A comment and a question, if the cyclone is exhausting to atmosphere then I have found a typical Grizzly style short cone works as well as a long cone and the exhaust debris are not noticeable.

    James, Can I clarify your comment above about impellers please, I had a quick look at Grizzly's site and I can't see any impellers available for sale as a single item. Are you referring to impellers on their own or machines with different size impellers?
    Chris

    Everything I like is either illegal, immoral or fattening

  14. #14
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    Chris,
    don't you have a clearvue?

    For the grizzly impellers, you need to search by the part number (most of their tools include a helpful parts list with these), as opposed to just searching for "impeller".

    E.g., the 12-3/4"x95mm aluminum impeller that is used on several of their DCs: https://www.grizzly.com/parts/grizzl...1/p1029z2010v2


    Matt

  15. #15
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    Thanks Matt. I was the Australian agent for Clearvue and introduced the product to Oz with success but the current agent has been forced to stop importing due to transport costs. We are now finding that cyclones of decent capacity from any source are nearly impossible to buy and it has become clear that making them here is the way forward at least for now. A source of impellers is the main problem as making them here does not scale well against the retail sales numbers.
    Chris

    Everything I like is either illegal, immoral or fattening

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