Help me pick out couplers for my grain mill / motor

[Ghostnuke]

I need to find some lovejoy couplers for my motorized grain mill project, but I've never messed with them before so I'm kind of out of my element.

My mill is a Cereal Killer, which according to the comments here, has a 3/8ths shaft.

The motor is a Bodine I picked up from ebay. The company was nice enough to send me some specs.

Does that say that the motor has a 3/4 shaft? Is it possible to get two different sized couplers? Any help would be appreciated.

 

[day_trippr]

Absolutely you can mate coupler halves with different shaft sizes - unless you're incredibly lucky it's pretty much a requirement.

I used to run a Barley Crusher, and that mill had a true 3/8" drive shaft which I coupled to a GE gear motor with a 1/2" drive shaft. I used Rotex aluminum KTR 19 coupler halves with their flexible "guibo". Worked fine 'til the mill lost its grip.

I replaced the BC with a new CK a month or so ago. The CK drive shaft reads 25/64" using a micrometer. May be metric, I dunno, but a true 3/8" coupler likely will not slide on - my 3/8" KTR certainly didn't, until I bored it out to fit...

Cheers!

 

[govner1]

You can easily get Lovejoys that will work with two different shaft sizes, that’s one of their principal intended uses.
Yes, based on the drawing the motor shaft is
0.745” (3/4”) but you also need to note that the shaft is “keyed” so you need a Lovejoy that accommodates a 3/4” keyed shaft.

 

[Ghostnuke]

Absolutely you can mate coupler halves with different shaft sizes - unless you're incredibly lucky it's pretty much a requirement.

I used to run a Barley Crusher, and that mill had a true 3/8" drive shaft which I coupled to a GE gear motor with a 1/2" drive shaft. I used Rotex aluminum KTR 19 coupler halves with their flexible "guibo". Worked fine 'til the mill lost its grip.

I replaced the BC with a new CK a month or so ago. The CK drive shaft reads 25/64" using a micrometer. May be metric, I dunno, but a true 3/8" coupler likely will not slide on - my 3/8" KTR certainly didn't, until I bored it out to fit...

Cheers!

The website itself lists the CK as having a 10mm shaft, whereas the comments say it's actually 3/8. 25/64 would be 9.9219mm, and 3/8 would be 9.5250. Should I be looking for a 10mm coupler instead of 3/8 then?

 

[mongoose33]

The website itself lists the CK as having a 10mm shaft, whereas the comments say it's actually 3/8. 25/64 would be 9.9219mm, and 3/8 would be 9.5250. Should I be looking for a 10mm coupler instead of 3/8 then?

First thing I'd do is get a micrometer (or really good dial calipers) and check to see what the shaft diameter really is. Same with your motor's shaft diameter.

 

[Ghostnuke]

First thing I'd do is get a micrometer (or really good dial calipers) and check to see what the shaft diameter really is. Same with your motor's shaft diameter.

ehh, I don't have a micrometer. day_trippr measured his CK with one, so I'll trust him, and Bodine gave me the blueprints so I'll assume those are right too. I'm sure my assumptions will bite me, but we'll see

 

[matt_m]

McMaster Carr sells the halves and the rubber spider as individual parts. They won't tell you shipping up front but its never very expensive.

I could have sworn the Cereal Killer had a metric shaft but I sold mine so I can't check.

 

[day_trippr]

The website itself lists the CK as having a 10mm shaft, whereas the comments say it's actually 3/8. 25/64 would be 9.9219mm, and 3/8 would be 9.5250. Should I be looking for a 10mm coupler instead of 3/8 then?

I had missed the 10mm drive shaft diameter stated on various retail sites, but that totally makes sense given my micrometer reading.
So, yes, get a 10mm coupler unless you want to bore out a 3/8" like I had to

Cheers!

 

[govner1]

You can contact your local Lovejoy distributor and they’ll order for you, too.
Don’t forget the key on the motor shaft.

 

[Ghostnuke]

I emailed them the specs for everything and they gave me this parts list:


L075 hub 10mm n/kw 68514441456

L075 hub ¾”, 3/16” kw 68514410690

L075 spider, NBR 68514410621

 

[govner1]

Make sure you have a flat spot on your mill shaft to keep your set screws on the Lovejoys from slipping.
Obviously not a problem with the keyed shaft.
Also use some thread lock on the set screws

 

[Ghostnuke]

Just wanted to update that the parts list I posted is correct. Someone may want to reference the measurements for the Cereal Killer later...

 

[acidrain]

Can you link the motor you got from ebay?
Be sure to follow up with a review and pics of your work!

 

[Ghostnuke]

Can you link the motor you got from ebay?
Be sure to follow up with a review and pics of your work!

I'll have to check the specs on the motor when I get home. The one I bought ended up being bad, so the vendor sent me a similar one but brand new.

I did post pics in the Motorized Grain Mills: Time to show them off! thread.