# Hammermill RPM's



## Stephen in SOKY (Jun 6, 2006)

Anyone know what RPM a Fairbanks Morse model 40 (10") hammermill should be run at?


----------



## milkman (Feb 3, 2007)

Don't know for sure, but I'd try 540 rpm if that's not fast enough try 1000.


----------



## agmantoo (May 23, 2003)

This hammermill is an old stationary type isn't it? I cannot substantiate my information but I think they were to run around 1100 RPM at the cylinder in the mill. Watch the rate you feed the mill and it should work at the 1100 rpm speed. There is a determination method for establishing the feet per minute of the hammers that is used to establish the RPM.


----------



## Stephen in SOKY (Jun 6, 2006)

Thanks for the answers. Yes, it's an older staionary unit. I was afraid 540 direct (Through a slip clutch) wouldn't turn it fast enough. Looks like I'll be looking at pulleys huh? Anyone out there have any experience (Photos) converting 540 PTO to 1000 rpm in an application such as this? Thanks again


----------



## uncle Will in In. (May 11, 2002)

What does it have on it now to drive it? If it's a pto shaft hook it to your tractor and wind it up. The old hammermils ran with the 540 pto unless they had a pulley made for a flat belt that was driven by the drive pulley that the old tractors had on the side of the gears in front of the rear wheel.


----------



## Stephen in SOKY (Jun 6, 2006)

Yep, she's got a flat belt pulley. It would be fairly simple to convert to straight 540 pto if that would turn it fast enough? However, it seems I may be looking at sprockets & chain sized to speed her up? Hate to waste the money converting to 540 pto, only to find it's not fast enough.


----------



## rambler (Jan 20, 2004)

I see tractors rated at 1000 - 3000 foot per minute belt pulley speeds.

You'll need to do some mather to figure out how fast turns the shaft on the hammermill. Will depend on the pulley size.

I'd say 540 will be way too slow, and 1000 would also be some too slow.

I would not want to run a chain on a high-speed hammer mill. Really fast, & lot of shock load. Might not be good. Belts stretch.

--->Paul


----------



## Stephen in SOKY (Jun 6, 2006)

Thanks for the input. I've gotten photos of one running on belts from another member, but I'm seriously looking at the truck tire to existing belt pulley to up the RPM's. I really appreciate all the input, if anyone else has anything to share, keep the advice coming!


----------



## agmantoo (May 23, 2003)

What RPMs did you conclude that the hammer mill itself should turn?


----------



## Stephen in SOKY (Jun 6, 2006)

Well, I haven't concluded where it should run yet. I've been told anywhere between 1100 and 2300. I plan to try this range & determine what works best. My 2240 doesn't have a 1000 rpm PTO, if it did, I suspect I'd try direct shaft. Don't suppose anyone has a operators manual for a Fairbanks Morse model 40???????


----------



## DaleK (Sep 23, 2004)

Most mixmills are hammermills. I'm just going by memory on ours but I'm thinking the ratio between the pulley coming off the 540 PTO and the one driving the mill itself is probably in the area of 1:5. You might try finding an old mixmill at a wreckers, if the mill is worn out the pulleys should still be good and should work.


----------



## Stephen in SOKY (Jun 6, 2006)

Lordy, I'd love to find a rusted out grinder/mixer. Rotten augers, daylight through the mix bin, no wheels, I wouldn't care!


----------



## farminghandyman (Mar 4, 2005)

It's been a wile since I have looked at it but I think "3000 rpm" is silk screened in to the side of my John deere hammer mill, I will try to check on that number in the morning,

but here are a few sites that may help,

http://www.meadowsmills.com/prod02.htm

http://www.feedmachinery.com/glossary/hammer_mill.htm 
there is a section on figuring the speed of the hammers, an thus the rotation, speed.

~~~~~~~~~~~~
http://www.bulkprocessequipmentandbulksystems.com/Hammermills.htm
this place has a chart that has the rotor size and recommended rpm for the diameter of the rotor,

Model Rotor Diameter Typical Horsepower Mill Speed (Maximum Rotor RPM) 

rotor width/model--rotor diameter,--horsepower for there mills,--max rotor RPM
W-6-L 9" 2 5,000 
W-8-L 9" 3 5,000 
W-8-H 16" 5-20 3,600 
W-12-L 16" 10-20 3,600 
W-16-L 16" 10-25 3,600 
W-12-H 18" 15-50 3,000 
W-16-H 18" 15-50 3,000 
W-20-L 18" 20-50 3,000 
W-25-L 18" 20-25 3,000 
W-20-H 24" 25-75 2,800 
W-25-H 24" 25-75 2,800 
W-30-L 26" 50-100 2,400 
W-36-L 26" 50-100 2,400 
W-30-H 30" 50-150 1,800 
W-36-H 30" 50-150 1,800 
W-40-L 30" 50-150 1,800 
W-50-L 30" 50-150 1,800 
W-60-L 30" 50-150 1,800 
W-40-H 40" 60-200 1,200 
W-50-H 40" 60-200 1,200 
W-60-H 40" 60-200 1,200


----------



## farminghandyman (Mar 4, 2005)

I had to go to the barn and get a gallon of milk, so I checked the old mill, and it was "3000 RPM" and the rotor is about, 18" diameter.


----------



## Stephen in SOKY (Jun 6, 2006)

Thanks Handyman!


----------

