[ZipSnipe]

Ok I,m just about finished up the manual mill project http://www.cnczone.com/forums/showthread.php?t=18992
I was turning a pulley last nite when I realized that the diameter is a little small after I take off the metal I had to for the spanner nut( wall thickness is on the thin side) I figured it will be ok until I make a bigger pulley. So my question is , I currently have a 1:1 ratio with an rpm of around 3000 and pulley sizes are 2 1/2" diam. I was thinking of making my spindle pulley at 3" and leaving the drive pulley at 2 1/2" I know it will reduce the speed but I don,t know by how much and I wanted to see if you guys can tell me(Pretty please) what my speed will be reduced to and if I would still be ok to mill aluminum and steel? Oh yeah and I currently have a 22" belt if I go up a 1/2" in diameter on one pulley will my belt size be 23"?

[ajl6549]

approx. belt size = 22.8, 16.6667% slower or 2500 rpm

[ZipSnipe]

Kool , Thanx, I figured a way to leave a little meat on the pulley I turned on my lathe. Now I got to make a custom spanner wrench(the reg spanner wrench tightens the nut from the side, I need one to tighten from the top)