Question for Bill Pentz Cyclone Builders

[Dale Critchlow]

I am building Bill's "Budget Blower" using the 5hp Leeson motor and the 14" Sheldon impeller and have a question about the spacing between the impeller and the motor.

I mounted the impeller on the motor shaft by sliding the tapered fitting on until its top end aligns to the top end of the key in the motor shaft. (This assumes that the orientation of the motor/impeller assembly is the same as it would be in operation.)

After I tighten the three small bolts of the tapered fitting, I find that I have 1 5/8" between the top of the impeller and the bottom of the metal motor plate. Bill's drawings show this dimension to be 7/8". Therefore, the spacing between the top MDF and the impeller will be 1 1/4" rather than 1/2" shown in Bill's drawing. (The MDF is 3/8" thick under the metal motor plate.)

I contacted the Electric Motor Warehouse since I thought they may have sent me the wrong motor. They responded as follows: "This motor has a standard 145TC frame size, which has a standard shaft size of 7/8" diameter and 2 1/4" length. We have not had any problems with this motor and Bill's design, so you should be ok."

Of course, I can adjust the width of the sheet metal spiral to accomodate the extra spacing.

My questions are:

1) Have other people seen this spacing in their systems? That is, 1 1/4" between the top of the impeller and the bottom of the MDF.

2) Does the extra 3/4" of spacing affect blower operation? (My guess is that it won't but I am not sure of this.)

Thanks,

Dale Critchlow

[Jay Albrandt]

Dale,

I cut and routed my MDF blanks according to Bill's instructions. I also had the sheet metal cut to his specs, and I "dry" assembled the blower housing. I mounted the motor on the metal disc, and reaching in through the blower outlet, I measured and marked the exact location of the collar on the shaft to give me the correct spacing from the bottom of the impellar to the top of the blower housing. If you read through all of Bill's information, he is pretty specific about this distance. Bill is done his research when it comes to blowers and cyclones, so there is probably a good reason for his specs.

I love my unit (bought the cyclone kit and did the assembly)! Although I have nothing to compare it too, I can't imagine something performing better. This think sucks!

Good Luck!

Jay

[Jay Albrandt]

Dale,

I cut and routed my MDF blanks according to Bill's instructions. I also had the sheet metal cut to his specs, and I "dry" assembled the blower housing. I mounted the motor on the metal disc, and reaching in through the blower outlet, I measured and marked the exact location of the collar on the shaft to give me the correct spacing from the bottom of the impellar to the top of the blower housing. If you read through all of Bill's information, he is pretty specific about this distance. Bill is done his research when it comes to blowers and cyclones, so there is probably a good reason for his specs.

I love my unit (bought the cyclone kit and did the assembly)! Although I have nothing to compare it too, I can't imagine something performing better. This think sucks!

Good Luck!

Jay

[Jay Albrandt]

Sorry for the Double Post!

[Jim O'Dell]

I'm installing my Clear Vue (Bill's design) this weekend, too. I had to work part of today, so didn't get much done, but I did mount the impeller early this evening. I just measured the spacing on mine, and I have a 3/8" gap between the 3/4" bottom MDF motor plate and the flat top plate of the impeller. The shaft is about 1/16" below the surface of the taper lock. Now, I don't have the Sheldon impeller, so that will make a difference. I'm using the new impeller that Ed Morgano and Bill Pentz designed and had built by Martin Sprocket and Gear. But something tells me it is very similar in size. The height of this impeller is 4 1/4" from the top of the flat plate to the tip of the fan blades. The hub is about 1 1/4" from the flat plate. My impeller plate JUST clears the bolt heads for the motor mounting. At first the set screw would not hit the key in the shaft, so I had to counter sink the bolts a little.
Not sure any of this will help, since it's slightly different equipment. I'll be interested to see what some of the others have to say. Chris Padilla should have his about together, maybe he will chime in. Good luck with your install!
And is it just me, or do the fan blades seem to be backwards? It looks like it will be a blower instead of creating vacuum. But I looked at the pictures for the Clear Vue install on Ed's web site, and mine looks like his, so I guess it's right, and I'm just confused! Jim

[Dale Critchlow]

Jay: The problem is that you shouldn't slide the tapered fitting too far onto the shaft. The end of the of the fitting toward the motor should be lined up with end of the key on the motor shaft. Then you can use the small screw in the tapered fitting to tighten down onto the key. If you slide it on further than that the set screw will not hit the key.

I suspect that the shaft on my motor is longer than that used by Bill in his design.

Thanks,

Dale

[Chris Padilla]

http://www.sawmillcreek.org/showthread.php?t=9933

This thread addresses this very issue, Dale.

[Dale Critchlow]

Chris: Thanks for the suggestion. In fact, I read the thread you referenced before I started to assembly the blower. I have also read it several more times since I got stumped.

The problem is that when I position the tapered fitting as close to the motor as I can, while still completely overlapping the key in the shaft, the gap is larger than Bill's design.

I could push it closer to the motor but then the key will only be partially engaged. Also, the small set screw in the tapered fitting would no longer contact the key. Is this what people are doing? I am concerned that this might not be safe.

Does anyone know what the shaft length is for their 5hp Leeson motor? I am still wondering whether they sent me the wrong motor even though they insist they didn't.

Thanks,

Dale Critchlow

[Jim O'Dell]

Dale, the best I can tell with my motor mounted to the plate, and the impeller mounted to tthe shaft, measuring from the face of the motor to the shaft tip is about
2 1/8". I know there is a lip on the face that protrudes toward the end of the shaft...I could not measure for this as it is recessed inside the wooden motor mounting disc. I'll attach a picture to try to illistrate. Jim.

[Dale Critchlow]

Jim: Thanks for the response. It looks like your motor has a 2 1/2" shaft like mine. I have a couple of questions:

1) How far in did you mount the tapered fitting relative to the key?

2) Could you use the small set screw in the tapered fitting to hold the key in place? Or was the set screw past the end of the key?

Dale Critchlow

[Jim O'Dell]

Jim: Thanks for the response. It looks like your motor has a 2 1/2" shaft like mine. I have a couple of questions:

1) How far in did you mount the tapered fitting relative to the key?

2) Could you use the small set screw in the tapered fitting to hold the key in place? Or was the set screw past the end of the key?

Dale Critchlow

Dale, I had the motor on the bench, shaft up. The first time I set the impeller down on it, the set screw didn't even touch the key. Had to pull back apart and recess the bolts that go through the plate into the motor to gain some more space. When I put the impeller back on, the set screw hit within the last 1/4" of the key ( end of the shaft), but the key did cover the set screw hole. It was enough that setting the set screw finger tight with the allen wrench held the impeller in place. I then put the taper lock on and ran the screws down finger tight. Then I got the torque wrench out and torqued it to the prescribed settings. My taper lock is possibly and inch from the key. The set screw in the Pentz/Morgano impeller is in the fan section, not the taper lock part. So I may not be helping you much at all.
My problem was making sure I had enough clearance between the impeller plate and the motor mounting bolts that it didn't rub.Let me know how it goes for you this afternoon. My motor plate was sagging so bad when I mounted my motor and impeller on the stand I made that I had to make a run to HD for some angle iron to reinforce the plate before I could continue. I've got to move my setup up the stand now and anchor it in place, then attach one more section of insulation to the top of the stand for noise control, and then shove the whole thing about 8" back into the closet. We'll see if I have any time left to figure out if I have things worked out for the exhaust to clear or not! Jim

[Dale Critchlow]

Jim: Thanks for the information and the photo.

It looks from the photo that you using the motor plate to support the motor and impeller as well as the cyclone. The motor frame is very strong and it is better to hang the whole system from the base of the motor. Then the motor plate has to support only the blower enclosure and the cyclone. This puts a much lower load on the motor plate and doesn't experience starting torques, etc.

What material are you using for the motor plate? Your note makes it sound as if your are using MDF.

I plan to contact the Electric Motor Warehouse tomorrow to make sure there isn't more than one shaft length available. If not, I will probably make the top MDF plate of the blower thicker to reduce the gap between the impeller and the MDF.

I will keep you posted.

Dale Critchlow

[Jim O'Dell]

Dale, my motor plate is a single thickness of 3/4" MDF. It is the way this cyclone comes (Clear Vue). When I mounted it on the wall, it sagged badly. I had to go out and get some angle iron to stiffen it up. Since this is a kit, I don't think I should re-engineer it. Not sure I could anyway ;-). The mounting plate probably should be 2 layers of 3/4 inch plywood glued together. The cyclone body probably doesn't weigh 20 pounds. So it's not like the weight of a metal cyclone hanging on this. You may not have seen this unit, but it made out of PTEG which is a cross between Lexan and plexiglass. It is supposed to be very durable, according to a customer of mine that works in the plastics industry. I have updated my thread on my shop rehab with some pictures of my syclone closet. See: http://www.sawmillcreek.org/showthre...t=14427&page=4
You might ask Chris Padilla if he would mind sending you some of the pictures he took while assembling his. Hopefully he has some good shots of the motor plate, motor and impeller assembly. If available, maybe this will answer some of your questions. I believe his unit is just like what you are making. Good luck! Jim