Worm drive

I have a worm drive gear box that I am playing with as a possible 4th axis on my machine but the stepper config has me baffled. What do I need to enter for the pulley/gear settings and the leadscrew pitch in the step config

Pulled the drive apart and the worm is a 2 start thread with a 5mm pitch, the gear is 88 tooth. Physically rotated the drive shaft 44 times and got 1 rev of the output shaft

200 step stepper with 1/8th microstep (although that is adjustable)

Bill

Bill,

You will need to set the gear ratio as 1 : 44 if the stepper motor is direct coupled to the worm gear input shaft.
Then put the value of leadscrew pitch to be 360 degrees per revolution.

I think I would go down to a microstep of 1/2 instead of 1/8.

Thanks Nitro, thinking about it its logical that the pitch is 360.

Bill

bill516 wrote: What do I need to enter for the pulley/gear settings and the leadscrew pitch in the step config

Stepconf tries to be too helpful, and asks questions that can not always be answered.
Perhaps here should be a box to directly enter the step scale.

The final result of the multiple boxes in Stepconf is a single number in the INI file, the number of step pulses per machine unit.

In your case 1 degree is 44 / 360 turns per degree
If you are at 1/8 microstep then that is 200 x 8 steps per turn.

The number of steps per degree is thus 200 x 8 x 44 / 360 = 195.5555556

And that should be the number that you see in the INI file.

This also shows that you have a resolution of 1/200th of a degree but that you need 1170 Hz for 1 rpm. You might find that you can't make steps fast enough to turn at the rate you want, and that reduced microstepping will be needed.

Thanks Andy it was the pitch box that threw me.