cyclone dust machine for shop vac (secondary inprogress pics)

[Russell S.]

I thought i would share this with you guys since i know alot of you are all about working smarter.  so here is another home made gadget i just got done throwing together.  

It works like a dyson vacuum or a big dust tower, only it hooks up to your shop vac.  i used a 8" vent duct riveted in to a cone, some 2 inch PVC a 5 gallon bucket and some scrap ply wood to build it.  the hose couplers are flexible 2" couplers they are the most expensive part(8$ for both) and un necessary i was being lazy so i used them.  i need to get some bondo to smooth the rivets on the inside, make a bottom fairing and duct the inlet inside the cyclone.  i think it will work even better with those improvements.  vaccumed the the shop even under the band saw and didn't have any drop in suction. I may build a second stage like dyson uses with alot of small cyclones.  i will see if i can find a clear tub at walmart, it would be nice to run the vacuum with no filter at all.  

the cyclone tower
   

what is in the hopper after cleaning up
   

whats in the vacuum after cleaning up
   

sorry the pictures are rough.  if anyone would like a better look i will get the good cam out.

[Apex Predator]

Great job buddy!  I might have to build one of these babies.

[bjansen]

Thats really great Russell, you build some great home made tools.  I was just curious what you meant by duct the inlet inside of the cyclone?

[Russell S.]

the inlet pipe is is cut to the contour of the in side of the funnel.  i mean put a square 1 inch by 3 or 4 inch channel on the in side of the air inlet that flares out and spirals down a bit.  right now when it air enters the funnel is is not traveling completely tangential(along) to the walls. i think the fairings to smooth the inside are more important though.

[Russell S.]

if you do build one of these put a grounding strap on it some how.  my just shocked me pretty bad...  i should have known that dry air,  and friction in the funnel causes lots of static.....  for not i will not touch the funnel.

[cobbow]

Man thats a great idea.

Can you put up some pics of the cone and inlet?  

Thanks
Cobbow

[TimZeigler]

No doubt, great idea.  Would like to see some detailed pics of the setup.

[Russell S.]

so this was made with out any real design only a thought of what i wanted. i did try to maintain some ratios i found online for inlet size, outlet side and bottom of the cone size.  i autocaded the top and bottom circles then cut them on the band saw.  center holes are cut with a hole saw and sanding to size with a 1" drum on the drill press.  for the outer tapper on the top i set the disc sander to an angle that looked about right then sanding the outside of the circle, it was cut just out side the line.

here is the outlet (top) cap.
 

inside of the inlet
 

inlet support  

outside of the cone
 

bottom of cone out side bucket.
 

bottom of cone inside bucket
 

looking down the cone
 

I think i am going to make a second stage out of some clear acrylic.  I am going to base it on the ratios of the funnel's in my dyson vacuum's second stage (it is amazing how fine the particles its second stage gets).  i think it will have unacceptable head loss and end up just being a science project, but still a fun project.  also considering a additional first stage for water and large objects since the large objects get lodged in the dust down shoot.  i am going to see if a smooth fairing fixes that.  

if i use a first stage it will be a 5 gallon bucket with a 3-4" outlet and a 2" tangential inlet.  the bigger outlet will reduce air velocity and lift, so big stuff can just fall to the bottom.  i think it will be necessary since no funnel will be employed, with the large diameter of the bucket cross over from the inlet to outlet should not be a problem.  

I love applied mechanical principles so this project is right up my alley.

[Russell S.]

here is what i was thinking for a secondary  it has some design modifications from its donor design based on available material.
 

[bjansen]

Very impressive Russell. Thanks for sharing those details...it really looks great.

[Russell S.]

so i started working on the secondary.  i am still concerned about head loss.  I got lucky and found some acrylic champagne flutes at walmart.  they will make good funnels but will only support a 3/4 suction tube. based on available supplies i can only fit 4 secondaries in to the housing. >> total area of the secondary suctions is  1.74 square inches. (i really need 8 of these secondaries for optimal flow.)    were as the hose has 3.14 square inch cross section.     again this is most likely just a science experiment, maybe we will get some useful design data out of it...    i have to order a 6" housing tube and weld on so there will not be any progress on this for a week or so.  

here is where I am so far.

suport plate layed out on acrylic sheet ready to cut
 

funnel support plates with funnels and the tube i am going to use for the hopper.
 

here is the "tool" i devised to sand the flanges in the support plates.  I will use it on the upper and lower flange.  i am going to fill the top with bondo cause its still a bit unstable.  the bottom is filled with 5 min epoxy so i can chuck it in the drill with out crushing it.