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Thread: List of replacement impellers for HF dust collector?

  1. Ugh, wow! Well, your experience in the NE pretty much matches mine. Thatís a lot of dough for metal. 24 ga sounds a lot heavier than traditional heating ductwork, what was it like to work with?

  2. Quote Originally Posted by Carl Kona View Post
    With that small of a blower, just use the big box 5" hvac duct. There will be NO issue of collapse.
    Thanks Carl, great info. I hadnít even thought about collapse with 30 ga ducting, good to keep in mind. I do want to do the Rikon impeller, so will play it on the safe side, at least with reinforcements. And maybe some Kevlar gloves, given my history with that stuff. 🙂

    These wyes should come in-crimped allowing you crimp the correct end for Dust collector flow (worth verify that is still the case before you order)
    Another good call given that it seems like no oneís hoses or fittings of a nominal dimension ever want to fit to anyone elseís, and neither blue nor orange stores have much in the way of 5Ē fittings.

  3. #33
    Join Date
    Nov 2017
    Location
    Upstate NY
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    Quote Originally Posted by Allen Matsumoto View Post
    Ugh, wow! Well, your experience in the NE pretty much matches mine. That’s a lot of dough for metal. 24 ga sounds a lot heavier than traditional heating ductwork, what was it like to work with?
    Definitely was on the high side re: cost. It coincided with an unexpected windfall at the same time I was planning this, so it worked out (and paid for a canister filter, too).

    Working with the ducting was difficult, as I'd never done it before. Had to get some tools (crimper, proper snips, and many band-aids), but once I figured that part out it was mainly simple. Getting the snap lock to close was the most frustrating part, but once I figured out a 2 hose clamp method it went far better. It's a lot heavier than the 30ga, but with temp supports (one man shop here, so no one to hold things up) using pipe strapping, it went quickly.

  4. 5" duct

    Quote Originally Posted by Roy Petersen View Post
    ... and many band-aids


    Quote Originally Posted by Roy Petersen View Post
    ...once I figured out a 2 hose clamp method it went far better.
    Got a link to that method, maybe save me some band-aids? Or is at as simple as hose clamping partway in from both ends to get the pipe to close up enough to engage when released?

    Oneida's Gorilla clamp duct system looks pretty great, but wow, $45 for an elbow, I think I'll save the money for tools instead.

  5. #35
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    Nov 2017
    Location
    Upstate NY
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    Here was my post on it, but there are several ways within that thread.
    https://sawmillcreek.org/showthread....50#post2747450

  6. #36
    Join Date
    Feb 2013
    Location
    SF Baaaah Area
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    36
    Here in the SF Bay Area, I have a nearby commercial HVAC supply house that is able to order pretty much anything one may need -- let there be no mystery, these DC manufacturers are not creating their own specialized pipes and fittings, they are utilizing existing materials or customizing them, so we can do the same while cutting out the middlemen.

    I wouldn't trifle with 30ga., but simply order up 24ga, which isn't too expensive. At some point, ordering 5" spiral pipe might be feasible.

    Lastly, you can use adapters to overcome the 5" sizing issue. For example, the 5" inlet to the impeller is what limits the cfm, not the 6" pipe, so just run 6" if that's all you can find at a reasonable cost and reduce it with a commonly available 6"-5" reducer at the impeller. Another alternative, if you have only a short main, would be to convert the impeller inlet and outlet to a 1" larger diameter (the outlet must be 1" larger than the inlet).

  7. #37
    Join Date
    Mar 2015
    Location
    Birmingham, MI
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    I have to take exception to Bradley's comment about upsizing your duct to 6" from a 5" port. Although it seems innocent enough to increase the duct by 1", but your duct area is increasing almost 50% (~19 sq. in. to ~28 sq. in.) So the issue is the velocity drops in the bigger duct. I just ran an 8' run of 6" duct from the 6" outlet of a 1.5HP cyclone with a 12.5" impeller and my velocity was too low for duct collection (~2700 FPM) even though my CFMs were about 530. When you drop the velocity you can't maintain suspension of the debris in the duct and you get clogs. By simply reducing the duct to 5" diameter I increased velocity to over 3300 FPM with a drop in CFM to 490. With any dust collection system you want at least 3000-3500FPM velocity to maintain debris suspension (some even want >4000). That is why you never see ANY air system (Dust collection, vacuum or HVAC) increase duct size down the line.

    Most any blower, dust collector, cyclone with an impeller under 13" probably can't properly operate with 6" ducting, they would perform best with 5". Although many people run 4" due to cost and convenience, you strangle away too much performance. Will a 6" or 4" create suction? Sure. They will tell you it "feels great", "can't believe the suction" etc. but they did not accurately measure the performance. I did and my short run of 4" showed over a 30% drop from 5" so I didn't bother doing any more testing with that setup. Even the manufactures realize that 6" is too big for smaller blowers. Grizzly includes a 6"-5" reducer with their 1.5HP cyclones. Why even have a 6" port to begin with? Because they can advertised a bigger CFM number using a larger port.

    Hope that helps.

    Carl

    BTW All measurements were based on testing with a Pitot tube

  8. #38
    Join Date
    Feb 2013
    Location
    Tippecanoe County, IN
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    406
    Quote Originally Posted by Carl Kona View Post
    ... I just ran an 8' run of 6" duct from the 6" outlet of a 1.5HP cyclone with a 12.5" impeller and my velocity was too low for duct collection (~2700 FPM) even though my CFMs were about 530. When you drop the velocity you can't maintain suspension of the debris in the duct and you get clogs...
    You were getting clogs at 2700FPM? What kind of material were you trying to move?

    I use 6" flex and PVC to connect to my table saw and get about 400CFM which is about 2000FPM in the 6". I have not had a problem with clogs.
    Beranek's Law:

    It has been remarked that if one selects his own components, builds his own enclosure, and is convinced he has made a wise choice of design, then his own loudspeaker sounds better to him than does anyone else's loudspeaker. In this case, the frequency response of the loudspeaker seems to play only a minor part in forming a person's opinion.
    L.L. Beranek, Acoustics (McGraw-Hill, New York, 1954), p.208.

  9. #39
    Join Date
    Mar 2015
    Location
    Birmingham, MI
    Posts
    140
    David,

    Good to know you can maintain such a low velocity on a TS without issue. I have not had clogs on my current setup and did not want to deal with any either. I changed my duct size after my testing using clean new filters, which would have been my best case scenario. My concern at 2700 FPM was based on all the duct/material flow design guidelines I have ever come across regarding wood chips. Everything I have seen from duct manufacturers, dust collector manufactures (both retail and industrial) and wood working journals all use a
    minimum
    velocity for wood chips at 3500 FPM in designing ductwork branches. Since my best was only 2700 I didn't want to chance it. I am still not to my target, but this is temporary. If it was only my TS connected to this line I would not have been as concerned, but my jointer and planer make the bigger clogging chips. The only clog I ever had was with my planer and my old Jet 1100 using a 4" flex. Don't know how caked the bag was or how little flow I was getting at that time as I didn't pay attention to those things at that time.
    Hope this helps. Let Us know what you do.

    Carl

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