Well, I finally got my 2 X 72 belt grinder put together! The formula I'm using for surface feet per minute is:
Grinder shaft rpm X (3.14 x 10") _______ = SFM Where my contact wheel is 10"........
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My motor is a 1725 rpm, and with 2 step pulleys, I'm geting rpm's from 1725 down to 575. This yields SFM's from 4485 down to 1495. My problem is that this is still too fast for grits 180 through 1000, I've been told. Can anyone verify this formula, and maybe give some starting guidlines for various grits?? My step pulley are 234, and 456 for the drive wheel.
Thanks for any help here, guys!