Help Needed: Lovejoy Spider Coupling

I went ahead and bought a Barley Crusher and the motor that everyone seems to like nowadays: https://www.surpluscenter.com/item.asp?catname=&item=5-1098

However, I need help with the spider coupling. Can someone provide links to exactly what I need to buy at McMaster-Carr? The rest of the items (mostly electrical) I am fine with. It's just the coupling that I'm not sure what to buy.

TIA for the help!

John

I used the parts below, except my gearmotor coupling is 5/8" whereas yours is 1/2". I had to lightly sand the barley crusher shaft for the 3/8" coupling to slip on.

6408K73 - Buna-n Spider For 1-23/64" Outside Diameter, Flexible Spider Shaft Coupling Hub

6408K123 - Flexible Spider Shaft Coupling Hub, 3/8" Bore, 1-23/64" Od, without Keyway

6408K712 - Flexible Spider Shaft Coupling Hub, 1/2" Bore, 1-23/64" Od, with Keyway

Thank you lamar.

So, just to be clear, do I want to order those parts for my purposes? Or do I require different sizes?

Sorry...I really am Spider-Stupid!

Thanks for your help!

John

Yes, those should fit your shaft.

Sorry, couldn't resist.

I should have included the disclaimer that I am Irish! :S

Thanks for the help!

John

The shaft on that motor has a keyway. Why not use a keyed hub on it? Might as well take advantage of the keyway since it has one.

Catt22 said:

The shaft on that motor has a keyway. Why not use a keyed hub on it? Might as well take advantage of the keyway since it has one.

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Yup, the coupling for the motor has a keyway:

Crud! I already ordered. What I ordered will work regardless, right?

Wait...that is what I ordered (as yopu stated initially):

6408K712 Flexible Spider Shaft Coupling Hub 1/2" Bore, 1-23/64" Od, With Keyway

Lamarguy (or anyone else),

How do you like the motor listed? Does it have enough toque to not slow down when crushing wheat? My drill needs very slow feed of wheat in order to get through things on the Barley Crusher.

Joshua

jfkriege said:

How do you like the motor listed? Does it have enough toque to not slow down when crushing wheat? My drill needs very slow feed of wheat in order to get through things on the Barley Crusher.

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I use a Bodine 170 rpm gearmotor rated at 36 in/lbs. It's crushed all of the grain (wheat, rye, pale, etc.) I've fed it without fail.

I believe the minimum torque for a two roller mill is around 30 in/lbs. The linked motor is 40 in/lbs, so no worries.

Ok, so I have to admit to being confused. The reason that I asked is that the drill I use is rated to 240 in-lbs of torque, and will stop at times when doing a fine crush on wheat. What is going on with these ratings?

Is it that the motor above is rated for 40 in-lbs before the 10:1 gearing and comes out at 400 in-lbs after? I simply dont know what is going on.

Joshua

jfkriege said:

The reason that I asked is that the drill I use is rated to 240 in-lbs of torque, and will stop at times when doing a fine crush on wheat.

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Torque varies with RPM, so it depends on what RPM you're operating the drill at. Gearmotors operate at maximum torque when energized because the RPM is fixed.

30 in/lbs doesn't sound like much but it will easily brake your hand/arm.

jfkriege said:

Ok, so I have to admit to being confused. The reason that I asked is that the drill I use is rated to 240 in-lbs of torque, and will stop at times when doing a fine crush on wheat. What is going on with these ratings?

Is it that the motor above is rated for 40 in-lbs before the 10:1 gearing and comes out at 400 in-lbs after? I simply dont know what is going on.

Joshua

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Assuming you are using a cordless drill, the max torque output will only be achieved at full power with a fully charged battery that is in good condition. The battery power will decrease substantially as you use the drill and this may happen fairly rapidly under a heavy load as when milling grain. IOW, you may start out with the full 240 in-lbs of torque, but the drill won't likely be able to maintain that level of torque continuously for very long. The cheaper, lower quality drill motors will usually poop out much sooner than the high end models and Ni-Cad batteries sooner than the more advanced Litium Ion batteries. The cure is to buy a cheap 1/2" corded drill motor from Harbor Freight for about $40 or so. That or get the gear motor. The minimum torque recommended to operate the typical malt mill is usually about 50 inch-lbs, although many seem to get buy just fine on 40 or even as low as 30 in-lbs. The minimum torque requirements are not the same for all mills. You can also feed grain into a mill at a slower rate so that the rollers are not loaded full width which will make it easier to turn. Mills with wider rollers or multiple rollers will require more torque as will rollers with larger diameters.

Catt22 said:

The minimum torque recommended to operate the typical malt mill is usually about 50 inch-lbs, although many seem to get buy just fine on 40 or even as low as 30 in-lbs. The minimum torque requirements are not the same for all mills.

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FWIW, numerous folks operate their barley crusher with 30 in/lbs gearmotors running between 150 - 200 rpm. Three roller mills require more torque, probably 40 in/lbs.

lamarguy said:

FWIW, numerous folks operate their barley crusher with 30 in/lbs gearmotors running between 150 - 200 rpm. Three roller mills require more torque, probably 40 in/lbs.

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I am lucky my mill operates with 18 lb-in Bodine gearmotor.
To start with grain the mill requires starting torque close to 30 lb-in.
The mill mechanism was made by Automatic a large grain mill manufacturer.

Cheers,
ClaudiusB