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Too_Many_Tools
02-06-2010, 04:59 PM
On a small shaper, many use fixed speed motors and multi pulleys to get multiple speeds.

Has anyone refitted their shapers with variable speed motors and if so with what and how did it work out?

Thanks

TMT

dp
02-06-2010, 05:25 PM
If the speed controller also reduces hp/torque then the cutter may stall when cutting at low speed. That doesn't happen with pulleys when slowing down. At full speed with pulleys, hopefully the factory considered that and spec'd a motor/pulley arrangement that would get the job done without stalling. That's not quite the case on my Atlas shaper - it will definitely stall at full speed. :)

Too_Many_Tools
02-06-2010, 05:48 PM
If the speed controller also reduces hp/torque then the cutter may stall when cutting at low speed. That doesn't happen with pulleys when slowing down. At full speed with pulleys, hopefully the factory considered that and spec'd a motor/pulley arrangement that would get the job done without stalling. That's not quite the case on my Atlas shaper - it will definitely stall at full speed. :)

You bring up a good point...slippage...sometimes it is better for the drive mechanism to slip than the machine to break.

I have several shapers that I need to power...and your comment reminds me that I need to install drive systems capable to torque to that of which the manufacturer expected.

TMT

Al Messer
02-06-2010, 07:17 PM
How deep was the cut and how coarse was the feed?

Mcgyver
02-06-2010, 07:48 PM
I can't see an advantage to more speed control than the pulleys offer. On a lathe or mill, work or cutter dia changes all the time so you need to adjust spindle speed to get the surface speed you need. Not so on a shaper. you change pulley speed because you changed the length of stroke (which changes the ram speed); there's a limited range that is practical and the pulleys more than cover it.