Hi,

I'm considering building a larger router say 8by4 foot and have read that shopbot have been using closed loop stepper motor control.

Have have some pacific science nema 34's and micro stepper drives 6410-006 but the datasheet shows they are not closed loop, like most stepper drives.

I do have a few logic level industrial encoders and want to know is it worth connecting these up to a Gecko G-Rex 100 controller which supports encoder input for step feedback? Is close loop required for the average shopbot sized router, with or without a proper spindle?

When would I see such a benifit using them in closed loop control? I am thinking of rack and pinion drives for x and y while the z will probably be a ball screw. Not sure if that helps?

I understand that in closed loop systems the drives and/or controller monitors the movement for differences and tries to compensate. How often does a shopbot style router require this compensation? (sorry if this is a silly question).

Thanks,

DC
www.tea-with.me.uk