Additional stepstick extruders playing nice with onboard tmc2660

raykholo

This shows how to add a 3rd extruder via breakout and stepstick: https://duet3d.com/wiki/Using_external_drivers

Is it possible to use this and the first 2 extruder TMC2660 drivers together?

I read somewhere that for dynamic microstepping to work all the drivers had to be of the same type, so I would like to get clarification on this.

Thanks,
Ray

dc42

The restriction is that if you assign more than one driver to the same axis (e.g. to use two or three Z leadscrew drivers), those drivers must use the same microstepping. So there should be no problem with using a stepstick to drive a 3rd extruder, and different extruders can use different microstepping.

raykholo

Thanks for the clarification.

There may be a possible typo on that external drivers page, the TB6600 is rated to 4A max, not 5.

dc42

@raykholo:

Thanks for the clarification.

There may be a possible typo on that external drivers page, the TB6600 is rated to 4A max, not 5.

I've checked the datasheet and the TB6600 IC is rated at 5A peak, 4.5A "operating range maximal value". So I've changed the value 5A to 4.5A in that wiki page.

raykholo

Interesting. Every China vendor notes 4.0 peak and the box has settings shown up to 4.0 peak.

I do see your point about the 4.5 and 5A values concerning the IC itself.

dc42

The peak current you can use in practice will depend on how well the chip is cooled.