Help on pulley setup.

[Matlock]

I'm getting ready to buy a motor and pullies for the 50# Wisconsin Meyer trip hammer I have been rebuilding. I think I'll go with the 2HP 1750 rpm motor at harbor freight. That's the easy part. Now for the rest of it. The pulley on the hammer is 12" dia. and the spec's for a 50# lg say to run them at 250-300 rpm. If I am figuring it right that would mean a motor side pully of 1.71" - 2"? Now, do you guys with hammers suggest running a single v belt or multiple v belts, or is there something better out there. Also where is a good source for pullies? Any help would be appriciated.

Matlock

 

[Rick Baum]

Hi Matlock, I did some calculations of my own and initially I came up with the same diameter pullies as you did. However, I did some thinking (can be very dangerous and or confusing). I think that you came up with your calculations by using the 12" diameter instead of circumference of the hammer pulley. I'm not sure, but I think that it needs to be circumference instead of diameter. I came up with 1" and .85" pulleys. Hopefully someone with actual math skills will chime in. It's been way too long for me... My calculations are probably way off. I would like to know which way is correct. Can someone please help us? FWIW, all of the hammers that I have seen with v-belt setups have been multiple v-belts. Hope I didn't confuse you.

Rick

 

[Laredo7mm]

I have a 25 pound LG and I run her with a 2 hp motor, probably overkill but hey, power is good. I am thinking that you may want more than a 2 horse, but that is my $0.02.

As far as your calculations go, they are good. When trying to reduce/increase rpm, you can do your calculations directly from pully diameter. The circumferance comes into play when you are trying to figure out SFPM on grinders and stuff.

I have a single v-belt on my little giant and it works great. But it can't hurt to run two instead of one.

I would suggest not using an aluminum pully that is commonly available at most hardware stores. I have a steel pully on my drive motor. I got it from Mcmaster Carr. They should have just about any size you need.