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Chrism3
19th Jun 2010, 05:54 PM
I have a 4 speed lathe model GMF 1-TOOK1440 which I bought second hand some years ago but have only just dusted off to use.
Although the motor speed is given as 1440 rpm I do not know what the drive speeds are coming off the 4 pulley wheels - there is no 1:1 ratio, there are two up ratios and two down ratios.
I have the manual, but it does not specify the speeds. I suspect there may have been a sticker on the lathe that has fallen off .
Does anyone have one of these lathes, or alternatively can someone tell me how to calculate the speeds from the pulley diameters?
Any help appreciated.
Chris
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KevM
19th Jun 2010, 06:23 PM
Put the belt on each pulley position and count how many revolutions of your lathe spindle for say 10 revolutions of the motor pulley. This will give you a series of ratios.

Say you get 3 on the slowest speed this equates to 3 divided by 10 multiplied by 1440 = 432 rpm. Conversely say you get 20 turns for 10 of the motor pulley, this equates to 2880 rpm.

Chrism3
19th Jun 2010, 06:30 PM
Thanks Kev, so simple when you put it like that!
Chris

Allen Neighbors
22nd Jun 2010, 11:43 AM
Put the belt on each pulley position and count how many revolutions of your lathe spindle for say 10 revolutions of the motor pulley. This will give you a series of ratios.

Say you get 3 on the slowest speed this equates to 3 divided by 10 multiplied by 1440 = 432 rpm. Conversely say you get 20 turns for 10 of the motor pulley, this equates to 2880 rpm.


Now how'd you figure that out? :? I'm glad to know that.:2tsup: