Cyclone pic. (in progress)

[meika123]

I promised Barb (B4man) I'd post a picture of my cyclone progress, so here it is. It is painted Black as a base coat, will decide on a color later. Possibly Ivory-cause I like it. This photo shows the hole cut for the Neutral Vane which will be welded in later. Was going to mount the cyclone to the wall, but because of all the harmonics, I decided tobuild a stand, which gives me much more flexibility.
Here ya go, Barbara.

 

[Travis Porter]

That looks very good!!

 

[Alan in Little Washington]

Nice job! What gage steel? Are you going to use a spiral inlet ramp? What are you going to use for motive power?

 

[meika123]

Nice job! What gage steel?

24 gauge

Are you going to use a spiral inlet ramp?

No-just a neutral vane extending just over half-way thru the barrel.

What are you going to use for motive power?

Thinking about a Leeson 2.0 hp motor-3450 rpm, with a home-built 1/4" thick, 18" diameter aluminum impeller.

 

[Alan in Little Washington]

24 gauge



No-just a neutral vane extending just over half-way thru the barrel.



Thinking about a Leeson 2.0 hp motor-3450 rpm, with a home-built 1/4" thick, 18" diameter aluminum impeller.

You might want to do some checking, but that is a big fan for just a 2 hp motor. Except for overcoming inertia spinning it up, weight is not an issue, but I think the size will put a strain on that motor. ClearVue uses a 5 hp Leeson with their 15" and 16" impellers. Also, if you do match the motor to your planned 18" impeller, in addition to likely needing a 7.5 hp motor, you will also need to resize your cyclone to 20" or 22" diameter and ductwork likely to 8" or 9" diameter pipe! I would take a little time first and read through Bill Pentz site. All the parts must work together. It is like motors on sailboats- you can go 10 knots with a 25 hp motor or you can go 12 knots with an 100 hp motor.

Also, unless you can statically balance that sucker really well, you will get some pretty violent vibrations (and a dangerous situation) trying to make your own impeller.

 

[meika123]

Alan,
Your point is well taken. However on my present standard dust collector which I built, I am running a 19" diameter-1/8" thick four-bladed impeller with a 1.0 hp-1725 rpm motor, and it works great.
What do ya think the impeller size should be?
Thanks,

 

[b4man]

Dave,
Not only am I impressed, I'm dumbfounded :wtongueNo, it's not OK to comment on my condition:crossedlips
:rotflm:

Anyway, I am so lost when I see your pix and Fernhollowman's as well. I will need a lot more education on dust collection than I have now.
I will say that the way you described the parts you've done so far was accurate to the photo. I did understand that much just not much more.
Please update as you progress and thanks for showing us what you have done so far.

 

[Alan in Little Washington]

Alan,
Your point is well taken. However on my present standard dust collector which I built, I am running a 19" diameter-1/8" thick four-bladed impeller with a 1.0 hp-1725 rpm motor, and it works great.
What do ya think the impeller size should be?
Thanks,

With that big of fan and that small hp motor, you are getting close to a furnace fan! Of course it also depends on the width of each blade. Without rapidly exceeding my limited knowledge of air handling and fan curves, for an efficient DC with max CFM AND velocity, that won't burn up drawing too much current and overheating, I think the hp vs fan size matchups you see from the big cyclone retailers (Oneida, Grizzly, ClearVue) go something like this:

2 hp: 12" - 13"
3 hp: 14" - 15"
5 hp: 15" - 16"

Most of these fans have more than 4 blades and have reverse curvature to the blades- the ClearVue 15" and 16" impellers have 6 blades:

And these are all for 3450 RPM motors. No one is using 1725 RPM motors. Again, I can't recommend Bill Pentz's site enough.

 

[meika123]

With that big of fan and that small hp motor, you are getting close to a furnace fan! Of course it also depends on the width of each blade. Without rapidly exceeding my limited knowledge of air handling and fan curves, for an efficient DC with max CFM AND velocity, that won't burn up drawing too much current and overheating, I think the hp vs fan size matchups you see from the big cyclone retailers (Oneida, Grizzly, ClearVue) go something like this:

2 hp: 12" - 13"
3 hp: 14" - 15"
5 hp: 15" - 16"

Most of these fans have more than 4 blades and have reverse curvature to the blades- the ClearVue 15" and 16" impellers have 6 blades:

And these are all for 3450 RPM motors. No one is using 1725 RPM motors. Again, I can't recommend Bill Pentz's site enough.

Not to appear indifferent, or trying to argue, but if I have been using a 19" impeller with a 1.0 hp motor at 1725 rpm, why can I not safely use an 18" impeller with a 2.0 hp motor and 3450 rpm?

 

[McRabbet]

David,

The following is quoted from Bill Pentz's website:

"A few have made their own impellers but you need to know that the forces involved with a 14" or 15” impeller turning at 3450 RPM are measured in the tons. I have already had one welded impeller I was testing fly apart from those turning forces. I have not hit the ground so quickly since I served in the Vietnam War. There was little left of my blower and I was amazed that the heavy PETG plastic used in the Clear Vue Cyclones actually held up far better than the 18-gauge steel. The plastic was only scratched while the steel was punched clean clear through. Unless you really know what you are doing, making your own impeller or grabbing just any old impeller can be potentially life threatening. I see no reason to take this risk trying to save a few dollars while making my dust collection system, so strongly recommend use of a good quality impeller designed for this type of use."

In my personal experience, I know of a case where a ClearVue Cyclone 15" impeller was not secured to the motor shaft adequately and it destroyed the blower housing and impeller before it had spun up to full speed. Unless you have a significant imbalance in your impeller, I doubt this will be your problem. You will simply burn your motor out because a 2 HP motor does not have the capacity to turn a 19" impeller (assuming you have vanes that will generate the required airflows). Again, I'd agree with Alan and suggest you review the wealth of data that is included in Bill Pentz's site -- for example, in this section, you'll find details on impeller size, motor HP and performance with difference sized inlet ducts -- see the multi-color Blower/Fan Curves table under Impeller Size Test.

We're trying to help you succeed and suspect you need to research your system further before you proceed.