M906 guidance missing?
I wounder a bit about the M906 settings. There is some docu about it, sure. But I did not see any guidance how much current I should actually use. I think that the rule of thump is about 70 or 60% of the current in the data sheet, isn't it? But none of the howtos or G-Code explanation points me in this direction.
Is that a flaw or on purpose?
The amount of current is highly dependent on your motors and setup etc. so it's really a value you'd need to tune. 60-85% of max rated is the rule of thumb to target though.
I could add that rule of thumb to the M906 docs with a note to test and tune to balance for motor heat, noise, and torque.
Thank you very much.
I think that would help a lot of people, I had to buccaneer the rule of thumb from the marlin firmware at my very beginning with duet.
You can also go at it from the EMF calculator route and play with different values to see how it changes behaviour.
https://www.reprapfirmware.org/ And click on EMF calculator
@phaedrux That is a very good idea, indeed.
Well, I drive most of my steppers with the "rule of temp", I push up the current till I can barely touch the steppers with my index finger for 10 sec after 20 minutes of printing.
Would I recommend that? Absolutely not