i have made my own 55 gal tumbler. im trying to get the speed to 22 turns a minute, per cally morris instructions. im having a h*** of a time with it. my motor turns at 1725rpm. i have a 2" pulley on the motor, and went to a 10" pulley on a different shaft. then on that same shaft i put another 2" pulley. then went to the tumbler with a 8" pulley, and came up to 68 turns a minute. mathimatically, i thought that was right. thans what i get for thinking. i guess my math skills arent as good as i thought. but i cant figure out what pulleys i need to add to get the 22 turns i need. can anyone help me out with the math of this so i dont go broke buying diferent pulleys from my mathimatical ignorance. thanks in advance
bob
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Bob, here's the way I would figure it for the existing setup.
A 10" pulley and 2" pulley give you a 5:1 reduction (10/2). This would put the idler pulley at 345 rpm (1725/5). The 8" pulley and second 2" pulley give a 4:1 reduction (8/2) for a tumbler speed of 86 rpm. I would guess that if you came up with 68 rpm it was probably due to belt slippage.
Now, if my way of thinking is correct, you could go with something like this. A 16" idler and 2" drive (8:1 reduction) would turn the idler shaft at 216 rpm (1725/8). To get 22 rpm assuming you eliminated belt slippage use 216/22=9.8 reduction. Since you have the second 2" pulley, this would mean the tumbler pulley would have to be 9.8*2=19.6 or 20" diameter.
Now, you just have to account for the slippage and the fact that a 1725 motor doesn't turn that speed but I think more like 1700 rpm. This rpm difference is minor and the biggest issue is the slippage.
Good luck, Kirk
call me at 601-513-4813 and I will tell you what to do to make it work.
thank you guys for you help. kurti was doing the whole math thing way wrong. i was trying to figure out the cercumfrence of each wheel and how much it turned then breaking it down. i didn't even think of the ratio way. thanks again. joey, thanks for the photos. i believe i am armed with enought now to make this work.
thanks again
bob
Out of curiousity, how about a brief description of what Joey showed you.
Kirk