Need a little advise

[meika123]

Hey guys,
I need some advise from you. I am building a new impeller for my dust collector. It is built from .125 6061 Aluminum, and is 18 1/2" diameter w/ eight blades. My question is this: I acquired a mounting hub from McMaster-Carr to fit my motor shaft. The hub has a 3/16" keyway to match the motor shaft, but there is no locking set screw anywhere in the hub. Will this be safe running at 1725 rpm??
I would appreciate any input.
Thanks,
Dave in NC

 

[froglips]

It would help me to know which hub you purchased.

Any chance you need a key, not a setscrew?

And, hold the phone... You are makeing an impeller? That sounds like a fun tale to tell!

Thanks,
Jim

 

[meika123]

It would help me to know which hub you purchased.

I bought the BM style Bushing-Type H from McMaster Carr.

Any chance you need a key, not a setscrew?

It has a key, Jim.

And, hold the phone... You are makeing an impeller? That sounds like a fun tale to tell!

Not a big deal, really. As a matter of fact, I have built several. Here is the latest one.
View attachment 4372

Thanks Jim,

Dave in NC

 

[McRabbet]

The impeller on the ClearVue Cyclone uses a Maska "JA" tapered bushing that includes a keyway and locks onto the shaft. I would recommend that you include at least one set screw to lock your bushing to the shaft; two may be easier to provide proper balance.

 

[edspec]

Hello,

Most of the impellers that I have seen (usually on water pumps) have a threaded end to the shaft of the motor where either a nut threads onto the shaft or a bolt threads into the end of the shaft to lock the impeller in place. Most of the fans and blowers either use a set screw down on the key or a set screw down on a flat side of the shaft.

Not sure if there is any help provided in all of this. It would be a good Idea to check the amp draw of the motor once you have the impeller installed. If it exceeds the motor rating you may need to trim or adjust the blades so that you do not overload the motor.

Steve

 

[meika123]

The impeller on the ClearVue Cyclone uses a Maska "JA" tapered bushing that includes a keyway and locks onto the shaft. I would recommend that you include at least one set screw to lock your bushing to the shaft; two may be easier to provide proper balance.

The bushing is a squeeze fit on the motor shaft right now, w/o the key installed.
BTW: I have been using this impeller for years on my Homemeade DC, but with only 4 blades.

My bushing looks exactly like this Maska "JA"--The upper portion-with two threaded holes and two open holes for mounting.

Dave in NC

 

[toolman]

David;

I and/or my employees machine fan hubs all the time. (in are shop a fan is like your impeller but 4 to 8 times bigger.) You need a set screw over the key and one at 90 to 120 deg, Two set screws total. The fans my department works on run up to 5000 rpm. And Rob is also right on the use of taper lock hubs we use them as well. Oh yes the set screw needs to be a 10-32, 10-24, or a 1/4-20 will work as well. I would use a 10-24.

Added this after David post to Rob:

You do not need set screws in a taper lock hub.

 

[meika123]

Chad,
Now I'm a little confused. Are you telling me that I do not need to use set screws in my Hub. Are you familiar with the Type "BM" hub from McM-Carr? I appreciate the help.

Dave in NC

 

[toolman]

Chad,
Now I'm a little confused. Are you telling me that I do not need to use set screws in my Hub. Are you familiar with the Type "BM" hub from McM-Carr? I appreciate the help.

Dave in NC

The bushing is a squeeze fit on the motor shaft right now, w/o the key installed.
BTW: I have been using this impeller for years on my Homemeade DC, but with only 4 blades.

My bushing looks exactly like this Maska "JA"--The upper portion-with two threaded holes and two open holes for mounting.

Dave in NC

Dave

Confused that is my middle name. :rolf:

The photos above - Bottom photo is a taper lock, you have to use 2 bolts to lock the hub to the shaft. No set screws need.

The top photo is also a taper lock using 2 bolt to lock the hub. No set screws need.

I will pm you..

 

[McRabbet]

Added this ... post to Rob:

You do not need set screws in a taper lock hub.

Chad -- I'm aware that the Maska Taper Lock "JA" hub doesn't need any set screws -- I have a ClearVue Cyclone with a 5HP Leeson motor and the screws in the hub are used to pull the hub halves together to lock it tightly onto the shaft. But thanks for clarification for David and others. I am aware of a case when a hub was not installed securely and the impeller came off its shaft at speed, which was not a pretty sight.

BTW, if the hub that David is using is a 2-part split hub like the Maska JA and it is designed to tighten down on the shaft, wouldn't that suffice in lieu of additional set screws through the sides of the hub to secure it to the shaft? (I could not find any "BM" hub on the Mc-M Carr website).

 

[meika123]

See page 618 on McMaster Carr web page. It is a #19055K102, which is the same as 19055K1. That is the Hub I bought. It lists the hub in yellow at the bottom of the fan blade section.



Dave in NC

 

[McRabbet]

Not much detail on that hub, but I'd follow the advice that Chad provides -- his experience shows!