3 * RM1610 ballscrews, 780mm & 660mm

[JAZZCNC]

So what's the rationale for using pulleys to drive a ballscrew rather than connecting the stepper motor directly inline via a flexible coupling?

Couple reasons really.
Easy to gear for extra speed or resolution/torque. It also helps reduce resonance that affects the motors.

[Karl]

Couple reasons really.
Easy to gear for extra speed or resolution/torque. It also helps reduce resonance that affects the motors.

Many thanks - I hadn't considered the potential flexibility offered by interchangeable gearing.

That raises the question: What brand/source of pulleys/belts are currently in fashion/recommended?

{Presumably, belt manufacturers/suppliers provide tensioning guidance?}


Thanks

Karl

[JAZZCNC]

That raises the question: What brand/source of pulleys/belts are currently in fashion/recommended?

{Presumably, belt manufacturers/suppliers provide tensioning guidance?}

I always use HTD 5mm pitch 15mm width and a good brand is Gates, medway etc. If you go to any good bearing supplier and tell them you want quality brand not the cheap veriety they should be able to help.

[Karl]

... HTD 5mm pitch 15mm width and a good brand is Gates, medway etc...

Many thanks. Are more pulley teeth better than less? Eg for a gearing ratio of, say, 1:2 is there anything to be gained from using 12:24 teeth pulleys as opposed to 20:40 teeth?

Karl

[JAZZCNC]

Yes it's all about teeth in mesh.!! With small pulleys there are less teeth engaged between belt and pulley, less teeth engaged means less able to handle high loads and reduce the amount of torque that can be transmitted and if wrong will rip teeth off the belt.

Read these and it will explain lots. . http://www.roymech.co.uk/Useful_Tables/Drive/Timing_belts.html


http://www.ondrives.com/data/pdf/pul...belts-tech.pdf