Planned dust collection system

Started by DennisCA, September 24, 2014, 03:30:25 AM

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DennisCA

Well that motor sidetracked me a bit but I cut up the vanes today and boy the 12 of them turned out heavy, 3760 grams all of them, which is 8.3lbs, this is gonna be a heavy impeller. I wonder what the larger metal designs weigh...

Just the parts loosely together:

phil (admin)

It is actually a little difficult finding weights for blower wheels alone.  I went to eBay and found an aluminum 20" blower wheel that is about 20#.  But it is wider than yours and has a large hub installed:

http://www.ebay.com/itm/HUNTAIR-71100005-20-BLOWER-WHEEL-105-WIDTH-CW-BORE-1-3-8-175487-/361205375235?pt=LH_DefaultDomain_0&hash=item541984a103

But I think the answer to your weight question is, you're in the right ballpark.

DennisCA

Sounds good then! I had to cut a new disc, the smaller diameter of this pipe I went with was too different, so a new disc has been made and wider grooves, I epoxied them in place with slow setting epoxy, I also screwed them in with two screws per vane, then I trimmed the edges with my bandsaw circle cutting jig to make it proper round. I'm also considering putting construction adhesive around where the vanes meet the plywood and smear it out with a finger, to create a softer surface, fill in any gaps and to add even more strength.



There must be some trick of perspective because the inside looks off center, but looking above the individual vanes follow the interior guiding line, I've scaled it to work with an 8" main trunk, though I think I'll go for 6" all the way, maybe 8" after the separator as I understand it's helpful to increase the diameter afterwards for some reson.

I got a pretty serious angle on these vanes too... it sorta looks like an airfoil impeller...

Next step is to make a hole in the middle and try and balance it.

tvman44

Is there an advantage to larger line after the separator, larger than the line between the blower and separator?

phil (admin)

Quote from: DennisCA on May 26, 2015, 01:32:02 PM
I got a pretty serious angle on these vanes too... it sorta looks like an airfoil impeller...

It sure does, it will be interesting to see how this performs.

phil (admin)

Quote from: tvman44 on May 26, 2015, 02:51:46 PM
Is there an advantage to larger line after the separator, larger than the line between the blower and separator?

The input side typically has to be constrained to maintain enough fpm to keep debris entrained in the airflow.

No such requirement on the output side, the bigger, the better (provided you aren't taxing the motor).

tvman44

That is good to know.  Might try that on my little 1Hp DC for my down draft sanding table & router. :)

dabullseye

just wondering why u never used stooped dadoes due to the force and getting a good glue bond

DennisCA

I don't understand your question, I had to look up what a stooped dado was (not familiar with the english terminology) and it looks like what I called a groove, which I did make for the dadoes? For a better glue/epoxy bond, and screws in addition.

BernardNaish

Dado is the word used in the USA. In England it is a groove if along the grain and a housing if across the grain. Then again a rabbet is a small furry animal that is very good to eat.

DennisCA

Yeah I knew what a dado was, but not a stooped dado? Or rather it was likely a stopped dado, I thought the grooves I made in the disc qualified as such, hence my confusion.

dabullseye

oops i meant stop. im just thinking a pocket to trap the vane would lock it in place better. but it sounds like your gonna run screws up into the vanes. make sure you scuff up the surface to get a good bond

DennisCA

But I've made such pocket already, the vanes sit in them and are also screwed, this has already been done. If you see my latest picture and look you can see how the vanes are recessed & epoxied into place. They are also screwed into place from the other side, but you cannot see that in the picture.

dabullseye

i can see the dado or groove. what i mean is something like a mortice and a tenon on the vane

DennisCA

Not really sure how to make such a thing, some kinda jig on the router table perhaps. Still I am not sure the payoff would be worth it compared to just the groove and screws.