[groozier]

I have a sears 12" two speed bandsaw. I can't find my owner's manual and I'm needing to know what the rpms would be of the two speeds.I should be able to figure this out, but it is late and my brain has refused to think for awhile!!!!The motor turns 1725 rpms and it has a 1" pulley on the motor that lines up with a 4" pulley on the blade and a 1 3/4" pulley on the motor that lines up with a 3 1/2" pulley on the blade. Could someone please tell me the rpms on the two speeds and if possible how fast the blade is turning at each speed. 4-1 3.5-1.75
Thanks,
Lance Brooks aka groozier

P.S. It will probably be something easy to figure when my brain starts to work again!!!!!

[Claude]

are your pulley sizes the diameter (distance across), or the radius (distance from center of axle to edge of pulley) of the pulley?

Claude

[AlArchie]

SHOULD BE 431.25 RPM FOR THE 1.4 RATIO AND 862.5 FOR THE 1.75 TO 3.5 RATIO.

Do you need the blade speed in FPS or are you ok with the RPM?

OK the 4*1 ratio will produce a 271 fps blade speed
the 1.75*3.5 ratio will give 542 fps blade speed

Geeze, hope I figgered right!


Al

[groozier]

Thank you so much. I was so tired that I never put down about diameter or radius. The numbers are the diameters of the pulleys.Thanks again for the answers.
The reason that I asked the question is because sears has discontinued the two speed pulleys and offering the 3.5" and 1.75" as the replacements. I wanted to make sure that I was getting the higher speed pulley and not the one for cutting metal. 3.5 in. on the blade shaft and 1.75 on the motor shaft.
Thanks again.
Sincerely,
Lance Brooks aka groozier