Power For Grainmill???

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HopSong

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Ok, I've got a MM-3 and trying to find a way to power this baby.

Seems the recommended speeds are around 150 or so RPM. I'd rather not use an electric drill.. but.. ya never know.

Looking at gear motors.. wow.. expennnnnsive.
Looking at a 1725 or so rpm ac motor.. $100.. but to get it to 160 it looks like I'd need a 2" pully on the motor and about a 20" pulley on the MM-3.. seems out of this world

Solutions? I have a large 1/2 PorterCable plug in drill similar to the Harbor Freight drills.. but, I'd rather go something cleaner.

Thanks
 
I bought one of these:

http://www.ebay.com/itm/106-RPM-120V-Electric-Gear-Motor-FREE-SHIPPING-/190510520509?pt=LH_DefaultDomain_0&hash=item2c5b4fd8bd

and connected it to my Barley Crusher with a lovejoy coupling. The thing is a beast and doesn't break a sweat even when starting with hopper full of 18# of grain.

0gA35nb.jpg


6oPYCcD.jpg
 
Love your name.. one of my usernames on another forum is "smokenque"

Looking at the setup.. looks great. Says it's 106 RPM.. I thought the recommended was about 170 or so. What does the crush look like?
 
mine is a super-torquey DC that spins at 62 rpm. Speed isn't really an issue - you just load up the hopper and walk away - there are always things to be done - sanitizing tubing, measuring hops, etc.
 
Thanks.
In my opinion, slower is better.

The crush looks fantastic. Husks are split but mostly in one piece. I actually did some experimenting with different gap settings and conditioned vs un-conditioned. (link to pictures below)

http://imgur.com/a/sebY7

I settled on a gap of .045 and conditioning the malt before milling.

Works great on my rig. I mash in a 10 gallon rubbermaid with a domed false bottom, constantly recirculated (at full speed) in my E-herms. I get consistent efficiencies in the mid to high eighties
 
If you go bigger than 12"pulley on the grain mill it will hit the hopper FYI. I use 12" to 1.5" pulley' powered by 1/3hp motor (wish it was bigger).

deer 052.jpg
 
mine is a super-torquey DC that spins at 62 rpm. Speed isn't really an issue - you just load up the hopper and walk away - there are always things to be done - sanitizing tubing, measuring hops, etc.

Hey HG.. what are you using to get the DC?
BnB looks like he has a great option too..

Actually.. all of these ideas look great
 
Hey HG.. what are you using to get the DC?

I built a converter. I did a bunch of research and hit the all circuits forum asking questions.

90vdc converts to about 120vac - something to do with the square root of 2...

but basically a transformer, a large capacitor, and a bridge rectifier got my household current down to 90vdc.

Sadly, the transformer set me back about $60, so BnB's $40 for his controller was a good deal.
 
I bought one of these:

http://www.ebay.com/itm/106-RPM-120V-Electric-Gear-Motor-FREE-SHIPPING-/190510520509?pt=LH_DefaultDomain_0&hash=item2c5b4fd8bd

and connected it to my Barley Crusher with a lovejoy coupling. The thing is a beast and doesn't break a sweat even when starting with hopper full of 18# of grain.

Brew n Que.. Looking at the Lovejoy couplings you have. Can you buy them with different end diameters? IOW, If the pump is 1/2" and the crusher has a 3/8 shaft, do you have to buy two separate units or can they be purchased "mix n match"???
 
Brew n Que.. Looking at the Lovejoy couplings you have. Can you buy them with different end diameters? IOW, If the pump is 1/2" and the crusher has a 3/8 shaft, do you have to buy two separate units or can they be purchased "mix n match"???

I have been all over where you are going with my MM3-2.0.

I started with a 1.5" shieve and 10" pulley on the mill. It slipped a lot so I switched to a 12" pully. That worked pretty well but would slip occasionally with a high percentage of wheat. It would also not start with grain in the hopper.

I recently switched over to a 15:1 worm drive speed reducer. It works flawlessly with my dayton 1/2 hp, 1725 rpm motor. I can load the hopper with whatever I want and flip the switch and watch it chew through the grain. I love it!

Here is the speed reducer I used:
http://www.surpluscenter.com/item.asp?item=13-133-15-R&catname=powerTrans

Call Grainger for the proper coulpers and spider inserts. Their tech support is amazing at getting you the right products.
 
This is what I built . Direct Drive to prevent side load on the bearings. With the grain in the hopper it slows down to 250 to 300 rpms.
 
Last edited by a moderator:
Brew n Que.. Looking at the Lovejoy couplings you have. Can you buy them with different end diameters? IOW, If the pump is 1/2" and the crusher has a 3/8 shaft, do you have to buy two separate units or can they be purchased "mix n match"???


Yes, you can buy them mix n match.....I picked mine up as a set on ebay for about $12 from seller "carolbrent" AKA Hubbard CNC


*edit for clarity*
The couplers I used are the "L" type, in the "070" size
Lovejoy couplers are sold in a variety of sizes. Each size is available with a variety of bore diameters (in the size we are interested in, bore diameter ranges from 1/4" - 5/8")

Link to product catalog page
 
Yes, you can buy them mix n match.....I picked mine up as a set on ebay for about $12 from seller "carolbrent" AKA Hubbard CNC

Mix and match is a misleading way to describe love joy couplers.

The face diameter can vary and they need to be the same in order to mate up properly.

I encourage you to edit your post for future readers.
 
Jammin.. I guess you are correct.. technically. What I meant by mix n match was to have the same type/model coupler.. but have, say 1/2" shaft size on one side and 3/8" on the other end.. but, I'll bet you knew that. Be nice to be able to do it without having to find a bushing of some sort.
 
^you won't need any bushings, you can mate a 1/2" shaft to a 5/8" etc... You won't have any trouble putting your kit together.

You just need to make sure all couplers have the same face diameter as they are sold in different sizes. Personally, I called grainger and a technician was extremely helpful in selecting the correct couplers that would all fit. I just told him what size shafts I was connecting. Well worth the phone call.
 
^you won't need any bushings, you can mate a 1/2" shaft to a 5/8" etc... You won't have any trouble putting your kit together.

While the set screw is probably long enough to make this work, I advise against this. If you put a 5/8" bore coupler on a 1/2" shaft, the center of rotation of the coupler will be offset by 1/8". Worst case it would bind, best case you would wear our your hub/spyder rather quickly.
 
While the set screw is probably long enough to make this work, I advise against this. If you put a 5/8" bore coupler on a 1/2" shaft, the center of rotation of the coupler will be offset by 1/8". Worst case it would bind, best case you would wear our your hub/spyder rather quickly.


you misunderstand.

The Lovejoy is three pieces. One has a 1/2" bore, the other a 5/8" (or whatever sizes you need). the center piece is a spider. they mate, all centered nicely. Look up a google image for Lovejoy coupling to understand it better.

lovejoy-bush.jpg
 
Thanks guys.. I think I've got myself setup.. we'll see. Bought a motor.. already have the MM-3.. and just called Grainger.

I didn't realize the parts each came separately.. Each coupling is a separate number as is the spider. Three different parts to make the whole...

Yippy.
 
you misunderstand.

The Lovejoy is three pieces. One has a 1/2" bore, the other a 5/8" (or whatever sizes you need). the center piece is a spider. they mate, all centered nicely. Look up a google image for Lovejoy coupling to understand it better.

No, I understand how the couplers work, the issue is with Jammin's choice of language....what he MEANT was you can get couplings with different bore diameters, but the same OD. What he SAID was you can mate a 1/2" shaft (from a motor or mill) to a 5/8 (coupling)

^you won't need any bushings, you can mate a 1/2" shaft to a 5/8" etc...

Perhaps he could edit to clarify

Thank you, hang glider. Thought I was gonna have to bust out my crayons.

Have a swell day!
 
I ended up with the one Brew n Que recommended. Looks like it will be the most reasonable choice I could find.. When it arrives, I'll just have to build a mount for it.
 
I sure hope so.. I think I read somewhere that a minimum of 17 works. If not, fall back and punt. I saw a bunch of small motors that were very low foot pounds.. but were hv DC... like 90 to 115vDC
 
.. I think I read somewhere that a minimum of 17 works.
I had a 20 in-lb that would only work if I taped off part of the shoot to prevent the full amount of grain from passing through. What I read is that 40 in-lbs or more is what you'd like, but that 30 is the absolute minimum.
 
It looks like that motor is rated at 30 in lbs of torque. Is that enough?

I sure hope so.. I think I read somewhere that a minimum of 17 works. If not, fall back and punt. I saw a bunch of small motors that were very low foot pounds.. but were hv DC... like 90 to 115vDC

I had a 20 in-lb that would only work if I taped off part of the shoot to prevent the full amount of grain from passing through. What I read is that 40 in-lbs or more is what you'd like, but that 30 is the absolute minimum.

Someone correct me if i'm wrong, but I believe the torque spec is for the motor (minus the gear housing) So there are two factors in play, the torque of the motor and the reduction ratio of the gear box. In my case, the motor is 30 in/lb, with a 16.5:1 reduction ratio (1750rpm/106rpm). So my power at the shaft is 495 in/lb (30 in/lb x 16.5). The same motor with a 10:1 reduction ratio (1750rpm/175rpm) would only have an output power of 300 in/lb.

All of that said, this gearmotor (106 RPM 30 in/lb) works great hooked up to my Barley Crusher. It has no problem starting, even with a hopper filled with 18 pounds of grain.....perhaps I'll take a video of it in action next time I brew.
 
Someone correct me if i'm wrong, but I believe the torque spec is for the motor (minus the gear housing) So there are two factors in play, the torque of the motor and the reduction ratio of the gear box. In my case, the motor is 30 in/lb, with a 16.5:1 reduction ratio (1750rpm/106rpm). So my power at the shaft is 495 in/lb (30 in/lb x 16.5). The same motor with a 10:1 reduction ratio (1750rpm/175rpm) would only have an output power of 300 in/lb.

All of that said, this gearmotor (106 RPM 30 in/lb) works great hooked up to my Barley Crusher. It has no problem starting, even with a hopper filled with 18 pounds of grain.....perhaps I'll take a video of it in action next time I brew.

Your speculated torque figures are false. Gear motor stats are posted "as is". If you were to add an additional gear reduction transmission, then you could start multiplying numbers.


I'll be curious to see how it works out for the OP's MM3. The MM3 requires an immense amount of torque to run it smoothly. Looks like a sweet kit for a BC though. I like that the motor package you bought comes with a reverse switch.
 
Your speculated torque figures are false. Gear motor stats are posted "as is". If you were to add an additional gear reduction transmission, then you could start multiplying numbers.

Interesting....Prior to purchasing the gear motor, I ran my mill with a cordless drill. It's peak torque rating is 455 in/lbs...and although it did the job it was clearly a workout for the drill. There is an obvious mismatch in the specs here (30 in/lbs for the gear motor vs 455 in/lbs for the drill) Hopefully someone can help explain the reason for the difference.

Link to the drill specs:
http://www.ridgid.com/Tools/R86006-Compact-Lithium-Ion-Drill/EN/index.htm
 
Drills like that are basically a 18 volt electric motor with a variable speed (trigger switch) and an adjustable transmission, the max torque is at the highest setting and full speed which drops off dramatically as the battery loses it's charge.
 
Drills like that are basically a 18 volt electric motor with a variable speed (trigger switch) and an adjustable transmission, the max torque is at the highest setting and full speed which drops off dramatically as the battery loses it's charge.

Thanks for further illustrating my point. The drill has a peak torque of 455 in/lb under the best condition, and it can barely run the mill. So can anyone explain how a gearmotor rated at 30 in/lb can run the same mill without breaking a sweat?
 
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