Page 3 of 3 FirstFirst 123
Results 31 to 39 of 39

Thread: MERV 16 (or HEPA) Air Scrubber/ Filtration

  1. #31
    Join Date
    Feb 2011
    Location
    Central WI
    Posts
    5,666
    Quote Originally Posted by Phil Thien View Post
    Drum sanders are a challenge, even for conventional cyclones.
    Most cyclones are not designed for fine dust. Bags are generally used rather than cartridges due to the inevitable loading. Dave

  2. #32
    Join Date
    Apr 2010
    Location
    Nashville, TN
    Posts
    1,544
    Quote Originally Posted by Peter Aeschliman View Post
    I went pleat by pleat washing them with water. It took a long time to get the water running somewhat clear.

    Needless to say, I won't be reversing the air flow direction after all. I'll need to blow through the filters (inside out)... otherwise I'll be stirring up more dust than I'm catchin.
    So if you spent all that time cleaning them, why do you think there is a problem in pulling air outside to inside? I seriously doubt you would dislodge more dust with the fan than you did washing.

    Most industrial cartridge filters go outside to inside.

    Mike

  3. #33
    Join Date
    Jul 2007
    Location
    Seattle, WA
    Posts
    1,495
    They still looks pretty dirty, even after all of the cleaning... I think they'll still spew tons of dust. I'd rather not take the chance.

  4. #34
    Join Date
    Jul 2007
    Location
    Seattle, WA
    Posts
    1,495
    All,

    Just thought I'd follow up on what I ended up doing. Since my last post, I installed the ebay Cyclone with my 3HP impeller and set it up to exhaust outside, got a new shop vac and rigged up a Dust Deputy in front of it, set up the pentz-style air filtration units on my Wynn filters, and picked up a Dylos (the .5 micron unit).

    Re: the Wynn filters, I mentioned before that I spent a lot of time cleaning them out with compressed air and water, in the hope that I could change the configuration so that I could suck through the filters instead of blow into them. After the cleaning I was concerned that they were still so dirty that it was going to spew dust if I changed the flow direction.

    The dylos demystified that. I ran the filters in that configuration as a test, and the dylos definitively showed that it wasn't a problem. The setup couldn't be simpler. I bought two 750 CFM 8" inline fans. They seal perfectly to the round gasket on the wynn filters. I mounted them vertically in the middle of the two long walls in my shop, with 8" elbows on the exhaust to aim the air flow. They work really darn well- there's a very clear circular air flow in the shop now. The downside is that they're really loud- the motor isn't loud, but the sound of rushing air is. It's not so loud that I need hearing protection, but it produces a noticeable amount of white noise.

    What I love about this setup is that the filters are mounted at face level and below. Many people express concerns that ceiling-mounted air filtration units pull dust up past your face. That isn't a concern with this setup. One of the two filters is mounted on the other side of my assembly table where I do most of my sanding. The downside is that some of the filter is close to the wall, which under-utilizes the filter media. I'm okay with that trade off though.

    I wired the fans together on a timer switch, which works great.

    Here are some pictures of the filter units. Please excuse the messy shop- I had to take down my clamp rack system to do this (I now have to completely redo that) and I didn't bother to clean up before taking any pictures.





    Here's the lowest dylos reading I've seen so far. This is after running the filters for probably 30 minutes without creating any new dust. The number on the left is the .5 Micron reading. 75 and below is in the "excellent" range. It shoots way into the thousands when I use my table saw, despite above and below-table dust collection. But after about 10 minutes it comes back down to the 300 range.



    As for the new cyclone setup, on the one hand, I'm thrilled about venting the fines outside. No more worrying about filters. On the other hand, I've experienced a noticeable drop in suction. It still sucks really well, but my 4-bagger/thien baffle/wynn filter setup sucked noticeably harder (it spewed dust though- I never got a good seal to the bags). The cyclone is of decent enough quality for the price, although the circular part of the cyclone was very out of round (as you can just barely see in the below pic, I had to shim it to get it to sit snuggly in the ring I built). The gauge of the steel is relatively thin, so the top flat part of the cyclone pops in and out under suction. Not a major problem, but I do think it could benefit from some thicker steel. You get what you pay for though. For the price, I'm very pleased.

    I can tell you that a Clear Vue cyclone is in my future though. I'll give this setup a few years, but I do have that nagging "you get what you pay for" voice in my head.



    All said and done, the air quality in my shop is massively better now. I've decided that I need to wear a respirator while making dust, and let the dylos readings come down into the "good" air quality range before I take my mask off. I hate wearing my respirator, but I would hate losing lung capacity even more!

    Thanks everyone for your input on this project.

  5. #35
    Join Date
    Feb 2003
    Location
    newmarket, ontario, canada
    Posts
    276
    Peter

    Thanks for posting your air cleaner(s) solution; it's quite interesting and, given the Dylos particle readings, pretty effective.

    It's interesting to underline that maintain some kind of air circulation in the shop helps air cleaners to do their job.... on the basis of air particles will settle faster in dead air and be "unavailable" to be collected.

    One outcome seems puzzling.... I would have thought that with venting the "fines" collecting by cyclone outside would have boosted "the suction" rather than diminished it a bit, on the basis of removing the back pressure a cyclone filter adds to the system.

    thanks again

    Michael

  6. #36
    Join Date
    Jul 2007
    Location
    Seattle, WA
    Posts
    1,495
    Micheal, I was surprised by the suction loss as well.

    Before, I had thein baffles and the Wynn cartridge filters that I re-purposed for the air filtration units. I know that cyclones hurt suction, and that would explain why bill pentz recommends a 5hp motor with a 16" impeller... mine is only 12".

    But the before and after aren't that different- before, I had filters and the thien baffle. After, I have no filters and a cyclone.

    The body of the cyclone is 18"... from what I've read on Pent'z website, with my smaller motor and impeller, I should actually be using a 20" body, which would mean the cyclone would be too tall to fit under my 8' ceilings once scaled up.

    Anyway, in a few years I'm sure I'll trade up to a clear vue cyclone. Lucky for me, they're only a 30 minute drive from my shop... so I can save a lot on shipping costs.
    Last edited by Peter Aeschliman; 06-17-2013 at 2:58 PM.

  7. #37
    Join Date
    Nov 2010
    Location
    Anchorage, Alaska
    Posts
    1,617
    Peter,

    Just in case you don't already have this covered...

    You mention your DC is working harder now that it's venting outside. This is good because it gets the dust out where it belongs. :-)

    What are you doing to allow make-up air to re-enter your shop? Any pressure drop between outside and the inside of your shop must be created by your DC. This makes the DC work harder and starves your system for air, especially if you have a marginal / undersized impeller/motor setup. A rule of thumb for return air ducting sizing is that it should be 10X the area of the high-pressure duct to ensure you get the full benefit of outside exhaust. For a 6" exhaust this is a bit over 2 square feet. Have you tried opening a window or door to the outside to see if this makes a difference?

    Jim
    One can never have too many planes and chisels... or so I'm learning!!

  8. #38
    Join Date
    Jul 2007
    Location
    Seattle, WA
    Posts
    1,495
    Great point, Jim. The weather has been pretty nice in the Seattle area lately, so I've been working with the garage door open. I will definitely need to figure something out for the winter though- I had no idea the return air ducting needed to be 10x the area of my 6" duct. Sheesh, I'm not sure where I'm going to be able to make a hole that large. I was thinking that I'd come up with some kind of flap vent to save some heat for the times when I'm not running the DC, but it's going to take a lot of them to make 2 sqft!

  9. #39
    Join Date
    Nov 2010
    Location
    Anchorage, Alaska
    Posts
    1,617
    I'm planning around a similar issue for my Clearvue cyclone. I'm not exhausing outside but plan to close-in my DC for noise purposes. I'm looking at a rectangular gable vent (search the BORG for pictures) as something that will provide the area while leaving a finished appearance to the room.

    Just my $0.02..

    jim
    One can never have too many planes and chisels... or so I'm learning!!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •