Gehl 135 Mix All feed grinder

[oldfarmall]

Hello-

I recently bought a Gehl 135 Mix All feed grinder as a mechanics special. It needs alot of work, but I think I can get everything working good enough to grind a few loads of corn each year for my small beef cattle herd (currently 5 head). I need to go through the hammer mill and turn the hammers as they are badly rounded on the current edges of the hammers. I only have one screen with hole size 3/8". Couple of questions:

1. I assume the hammers are heat treated and not mild steel? Seems they would be easy to duplicate from flat stock?
2. Are the hammer shafts also hardened steel? Can a guy make new hammer shafts if they are grooved badly, and what kind of steel?
3. Do the hammer spacers need to be replaced when hammers are turned? Any idea how to tell how much wear the spacers have?
4. How compatible are the screens between Gehl mixers? What other models used same screen. Are all the 21" wide hammer mill screens the same dimensions and interchangeable aside from hole size?

Thanks for any advice or comments in advance!

-Jesse

 

[BarnyardEngineering]

Frankly, questions about metallurgy are wasted effort. Nobody paid attention to that kind of stuff "back in the day." They just used the equipment, and they're not around anymore. We're left to figure it out for ourselves.

If you want to know if something's hardened, drag a file across it. When the file cuts, it's soft. When the file just skates across, it's hard. You can also buy a set of hardness files off Amazon for about $60 if you want to get scientific about it.

I'd imagine if the shafts are badly worn, anything you make up has to be better. They might wear faster, but you're not intending to use this machine every day. Probably last you the rest of your life and then some.

 

[will-max dairy]

Hello-

I recently bought a Gehl 135 Mix All feed grinder as a mechanics special. It needs alot of work, but I think I can get everything working good enough to grind a few loads of corn each year for my small beef cattle herd (currently 5 head). I need to go through the hammer mill and turn the hammers as they are badly rounded on the current edges of the hammers. I only have one screen with hole size 3/8". Couple of questions:

1. I assume the hammers are heat treated and not mild steel? Seems they would be easy to duplicate from flat stock?
2. Are the hammer shafts also hardened steel? Can a guy make new hammer shafts if they are grooved badly, and what kind of steel?
3. Do the hammer spacers need to be replaced when hammers are turned? Any idea how to tell how much wear the spacers have?
4. How compatible are the screens between Gehl mixers? What other models used same screen. Are all the 21" wide hammer mill screens the same dimensions and interchangeable aside from hole size?

Thanks for any advice or comments in advance!

-Jesse

A couple of notes about the metal... I agree with BarnyardEngineering.

I would only add... these are hammers, so any treatment would be for "toughness," not "hardness"

Buying a hardened steel may only get you hammers that are brittle.

Also, these hammers should be hitting corn more often than they are hitting metal.

These factors, along with BarnyardEngineering's caveats would tip me toward not worrying too much about getting special metal for the hammers. I would also expect that just turning the hammers over to a fresh side will last a lifetime of grinding corn for a few beefers.

The one fact that trumps all of this thinking is... the grinding efficiency is mostly based on the sharpness of the screen, not the hammers. If the screen has sharp edges, you could grind corn with wooden mallets pounding it through...