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Texas_Red

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I have a Monster Mill 3 roller pro that I picked up really cheap because it needed a little work. I replaced the drive roller and all of the bushings. My first time using it I used my cordless Dewalt DCD796. On the low speed setting I had no problem driving it at a low speed but it did seem to make the drill get quite hot. So thinking a corded 1/2 drill would be a better choice I went to see what Harbor Freight had. I ended up getting this as it was on sale.

https://www.harborfreight.com/brand...-variable-speed-hammer-drilldriver-56404.html
Well it did not do the job at all. It wouldn't even start the mill at low speed. Eventually it would start but way too fast. Ended up switching back to my Dewalt which had no problems at all. Should I just keep using my cordless or do I need a better drill that has more torque at low speed.
 
That drill ^ has these specs: Speed (max): 2800 RPM.
That's way too fast for milling without a geared (speed) reducer.

You'd probably want this model:
https://www.harborfreight.com/75-amp-12-in-variable-speed-spade-handle-drill-63112.htmlSpeed (max): 0 to 550 RPM
I own the older model of that, with similar specs, used on an MM2. It runs at about half the max speed setting, effectively at ~150 rpm under milling load.
Should work well for your MM3 too.

Or this one:
https://www.harborfreight.com/75-am...lmixer-56179.html?_br_psugg_q=low+speed+drillSpeed (max): 0-600 RPM
 
OK that makes sense. The Dewalt on the low speed gear is 550 RPM. Didnt even consider that when shopping. Luckily I can exchange it.
Many brewers use their battery powered drill for milling, without issues. Those drills usually have plenty of torque, and are typically lower speed already.
Perhaps mill in 2 or more sessions and let the drill cool off in between?

For 1.5" diameter rollers, like your MM3, a speed of around 150 rpm is recommended. It translates to a linear speed of around 12"/sec (ips), which is ideal for milling malt/grain in brewing. Less hull shredding.
 
I have used the 1/2 Harbor Freight Spade drill suggested above with a regular MM3. I added a router speed control to be able to dial the rpm’s down further. I mounted it to the table using a bolt, some scrap wood, and some washers to the aux handle mount on the left side of the drill as well. It works great, it’s just really loud. I found that I still wanted to turn the speed down a bit and I suspect with the larger rollers of the pro that I would have really wanted to slow it down. I can get you a pic tonight if you are interested.

I also picked up of a used MM3 Pro in need of rehabbing. It’s being driven by a 1.5 hp, 1725 rpm motor with a 10:1 reducer.

Hopefully a link to the router speed control. Amazon is currently out of stock
https://www.amazon.com/gp/aw/d/B001NIK6PC?psc=1&ref=ppx_pop_mob_b_asin_title
MCLS has them
https://www.mlcswoodworking.com/shopsite_sc/store/html/9410-router-speed-control.html
 
What great finds on the MM3’s! I’m going start looking. I think the MM website indicates that the MM3 is too much for cordless tools. I have the MM2 with an old plumbing right angle drill that’s 550 rpm. the HF speed control does a good job dialing down the rpm’s even more.
 
I bought this for "jobs around the house" ie milling my grain + ice fishing auger. Works great. 2 batteries, so one is always charged. There's a lever on top of the drill with 2 settings - 1 or 2. I use it on the 2 setting (I'm guessing more torque?) with the drilling power to 14. It's just under the highest drill setting. Goes fast and crushes even the most stubbornly hard malt ie white wheat malt.

https://www.amazon.com/gp/product/B079N5B41N
 
I'm a Dewalt corded guy, personally.

P1040463.jpeg


But I have considered feeding spent grains to hamsters in a treadmill.
 
I use a DeWalt's XR 20V drill and it turns my 3-roller mill without hesitation, even at low speeds. It's never hiccupped once. I've milled wheat, which is harder, and again no problem.
I just bought the DeWalt 800 to replace my old drill driver and I'm thrilled with this thing.
My mill is cobbled together and uses a motor though. I didn’t have a large pulley to get the speed I wanted, so I cut one from plywood, grooved the edge just for proof of concept. It worked so good I left it as is. It eats grains like nobodies business and makes me laugh every time I use it.

 
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MM3 with harbor freight spade drill mounting
 

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deroosa, This is EXACTLY what I am wanting to do. I just purchased a 3-Roller Mighty Mill, and am still figuring out how I want to mount everything up. I will be purchasing a dedicated Mixing Drill to drive it.
 
Subbed. My new Mighty Mill 3-roller will be here tomorrow, and I'm concerned that my corded drill might be too powerful to run it. I have a 19v Kawasaki cordless drill, but have no idea where the charger is. A new charger is almost the same price as another drill so I'm waiting to see what the corded drill will do.
 
I'm concerned that my corded drill might be too powerful to run it. I have a 19v Kawasaki cordless drill, [...]
The main issue is the high speed these drills run at. They'll slow down somewhat when under load, but not quite enough. A low speed drill will give you much more torque.

See my posts #2 and #4, above, about speed vs torque.^

For grain used in brewing a linear mill speed of around 12"/sec (ips) is recommended. IIRC, I got that on a pro forum.

Roller diameter vs. drive speed (rpm):
For a 1.3" diameter roller mill (e.g., Barley Crusher, Cereal Killer):
Circumference = 1.3" * 3.14 = 4.082"
Drive speed: 12 ips / 4.082" * 60 sec = 176 rpm

For a 1.5" diameter roller mill (e.g., a Monster Mill MM2 or MM3) <==
Your Mighty Mill's 3 rollers are also 1.5" diameter (per their 'Questions' section)

Circumference = 1.5" * 3.14 = 4.71"
Drive speed: 12 ips / 4.71" * 60 sec = 152 rpm

For a 2.0" diameter roller mill (e.g., an MM2 2.0):
Circumference = 2.0" * 3.14 = 6.28"
Drive speed: 12 ips / 6.28" * 60 sec = 115 rpm
 
This is an alternate option that works rather well. It's a 50 rpm gear motor. I mill into the mashtun and store the whole shooting match in the mashtun too. I do really like milling hands free while setting up other things on brew day.


20220429_083907.jpg
20220429_081146.jpg
 
The main issue is the high speed these drills run at. They'll slow down somewhat when under load, but not quite enough. A low speed drill will give you much more torque.

See my posts #2 and #4, above, about speed vs torque.^

For grain used in brewing a linear mill speed of around 12"/sec (ips) is recommended. IIRC, I got that on a pro forum.

Roller diameter vs. drive speed (rpm):
For a 1.3" diameter roller mill (e.g., Barley Crusher, Cereal Killer):
Circumference = 1.3" * 3.14 = 4.082"
Drive speed: 12 ips / 4.082" * 60 sec = 176 rpm

For a 1.5" diameter roller mill (e.g., a Monster Mill MM2 or MM3) <==
Your Mighty Mill's 3 rollers are also 1.5" diameter (per their 'Questions' section)

Circumference = 1.5" * 3.14 = 4.71"
Drive speed: 12 ips / 4.71" * 60 sec = 152 rpm

For a 2.0" diameter roller mill (e.g., an MM2 2.0):
Circumference = 2.0" * 3.14 = 6.28"
Drive speed: 12 ips / 6.28" * 60 sec = 115 rpm
When I had my first mill, that I ran with a drill, what I did to keep the speed down was attach a big (3 or 4") hose clamp around the drill handle, over the switch; then used a screwdriver to adjust the speed just until the grain would run through. No idea what the RPM was but it was pretty low. Drill was plugged into a surge protector so I could easily switch on and off.
 
Nice setup! How did you mate the shaft on the motor with the shaft on the mill?
Thanks, the mill has a ½" shaft and the motor is ⅜" so a reducing clamping coupling was needed to join them together. It produces a great crush at low rpm for false bottom lautering.
 
I use this drill from HF. Works great even with misted grains. I adjust the speed to keep rpm as slow as possible based on feed rate after filling the hopper. My MM3 mill is set at .035”
1670508229258.jpeg
 
Here's the parts ordered from Amazon. The round wood base was picked up off the shelf in the lumber dept at Home depot or Lowes. It was a 60 min project 👍

View attachment 807321
Thank you for posting this as I've been looking into adding motor to my MM3. I have a question though. Does your power supply get warm when used? there's a couple reviews for that power supply that say the specs mentioned are incorrect and that the guage of the wires is smaller than what it's noted at which is causing a resistance issue and heating issues. I also noticed you used 18AWG wires and both reviewers say that for that size power supply the guage should be no smaller than 16. Would really like to hear your experience so far before pulling the trigger.
 
Thank you for posting this as I've been looking into adding motor to my MM3. I have a question though. Does your power supply get warm when used? there's a couple reviews for that power supply that say the specs mentioned are incorrect and that the guage of the wires is smaller than what it's noted at which is causing a resistance issue and heating issues. I also noticed you used 18AWG wires and both reviewers say that for that size power supply the guage should be no smaller than 16. Would really like to hear your experience so far before pulling the trigger.
Since July 21 this rascal has got a workout and neither the power supply or the motor have been more than, as warm as they should be. The crankenstein 3gt has never been below the recommended setting and the crush is fantastic, I can bank on 100% mash conversion. I can recommend the above configuration without hesitation.
 
When I had my first mill, that I ran with a drill, what I did to keep the speed down was attach a big (3 or 4") hose clamp around the drill handle, over the switch; then used a screwdriver to adjust the speed just until the grain would run through. No idea what the RPM was but it was pretty low. Drill was plugged into a surge protector so I could easily switch on and off.
I am recommending to build at least a sturdy platform mounting both the motor (or drill) and mill together, with the drive axles lined up perfectly. Not a luxury for the heavier mills and motors/drills, and much safer to operate hands-free.

I tried to hand-hold the drill, with the mill's (small) baseboard resting on the bucket. That went well for a few sessions until the mill apparently had locked up upon starting the drill, flipping a hopper full of grain sideways into the driveway. Almost broke my wrist, but surely bent the mill's 3/8" drive shaft. ;(

I was able to straighten the shaft, then built this:

Mounted Monster Mill MM2.0_1200.jpg
 
Sorry for the thread side hack but, I'm new to the Might Mill 3 and am curious what gap you guys are using and are happy with. Certainly YMMV and I'll play around but I'd like to hear what gap makes you happy.
 
Sorry for the thread side hack but, I'm new to the Might Mill 3 and am curious what gap you guys are using and are happy with. Certainly YMMV and I'll play around but I'd like to hear what gap makes you happy.
Honestly it depends on what kind of brewer you are. Are you BIAB or a false bottom mash tun?
 
Since July 21 this rascal has got a workout and neither the power supply or the motor have been more than, as warm as they should be. The crankenstein 3gt has never been below the recommended setting and the crush is fantastic, I can bank on 100% mash conversion. I can recommend the above configuration without hesitation.
Good to know! Thank you for the prompt reply and again for listing out all the parts! Did the motor come with the mount or did you buy that separately? I noticed in the motors description they reference
 
Good to know! Thank you for the prompt reply and again for listing out all the parts! Did the motor come with the mount or did you buy that separately? I noticed in the motors description they reference

I went to my local Ace and picked up the right effing metric mounting screws and some off the shelf L brackets. I let the L brackets into the wood base for perfect shaft alignment, rather than shim the mill.
 
Ok I BIAB with a stainless mesh basket and I believe i have mine at like 0.03 maybe a little smaller. It's been a while since I set it.
I brewed my first batch on Thursday with grain milled in my new Mighty Mill 3. I had the gap set at 0.035. I don't measure my efficiency (lazy), just gauge how good my crush is by what my preboil gravity winds up at. For BIAB I'm usually using 12-14lbs of grain (this one was 14), and strike with 10g of water. After the mash is done and I squeeze the bag, I wind up with just about 9g of wort. Grain bill was 8lbs pilsner, 4lbs two-row, and 2lbs wheat malt, mashed at 152°. Preboil came out to 1.041, a bit better than my usual 1.030-035. What really impressed me was the lack of a stuck recirculation; since I don't insulate my BK/MT, I have to apply a small amount of heat when the temperature starts to drop. Then I run the pump very slowly from the bottom and into the top to distribute the heat evenly. With the previous mill's crush (very fine) sometimes it would get stuck. Not this guy! Ran fine the entire 30 minutes. I'm going to brew again tomorrow, this time will condition the grain and tighten the gap down to 0.030 or thereabouts, and see what happens. Also going to use the mash tun instead of BIAB.
 
I brewed my first batch on Thursday with grain milled in my new Mighty Mill 3. I had the gap set at 0.035. I don't measure my efficiency (lazy), just gauge how good my crush is by what my preboil gravity winds up at. For BIAB I'm usually using 12-14lbs of grain (this one was 14), and strike with 10g of water. After the mash is done and I squeeze the bag, I wind up with just about 9g of wort. Grain bill was 8lbs pilsner, 4lbs two-row, and 2lbs wheat malt, mashed at 152°. Preboil came out to 1.041, a bit better than my usual 1.030-035. What really impressed me was the lack of a stuck recirculation; since I don't insulate my BK/MT, I have to apply a small amount of heat when the temperature starts to drop. Then I run the pump very slowly from the bottom and into the top to distribute the heat evenly. With the previous mill's crush (very fine) sometimes it would get stuck. Not this guy! Ran fine the entire 30 minutes. I'm going to brew again tomorrow, this time will condition the grain and tighten the gap down to 0.030 or thereabouts, and see what happens. Also going to use the mash tun instead of BIAB.
I used to have some issues with stuck mashes but recently found a product called Glucabuster. It helps breakdown things in the mash to allow for hassle free lautering. I'll use it in every batch moving forward because it works that good. It's pretty cheap. Consider checking it out. I'm fairly certain I bought mine from MoreBeer.
 
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