Denford Triac VMC w/ ATC conversion

[uli12us]

If you know the leadshines, I have seen, they offer a microstepping of 1000, 2000 and so on.
Do you know, if this works good. My machine have at the moment with 400 Mikrosteps a resolution of
1/100mm or 0,4thou. I must determine, if its metric or inches, But because all screws are metric, I hope the spindles are as well. With 2000µstep, I'll get a resolution of 1/1000mm that should be much better, if I want to make a real circle, or a tight fit.

[JAZZCNC]

If you know the leadshines, I have seen, they offer a microstepping of 1000, 2000 and so on.
Do you know, if this works good. My machine have at the moment with 400 Mikrosteps a resolution of
1/100mm or 0,4thou. I must determine, if its metric or inches, But because all screws are metric, I hope the spindles are as well. With 2000µstep, I'll get a resolution of 1/1000mm that should be much better, if I want to make a real circle, or a tight fit.

Depends on the figure your quoting is that 1000 PPR or 1000 x .? . . ie 200 x 1000.
The AM & EM have Max Stepping of 51200 PPR or 256x (200 x 256) They can be set in 2 ways Via Preset values With Dip switches on the drive Ie 400,800,1600 etc or using software in which case you can set to any Ms amount you like.
This parameter Configurabilty esp regards Resonance is what sets them apart from drives like Gecko's etc that leave you stuck with there preset values. In practise 99% of the time you don't need to change any of these parameters and software will Autotune it's self to the motor but in cases where you do they are life savers. Or if you want to tweak the machine to gain the best possible performance from the motors then you can if desired.

Also Don't think of Micro step as increasing Resolution that's not it's main function. It's more useful for motor Smoothness at lower speed. Having the Ms set too high just stresses the Pulse generator for very little to No gain in performance/resolution.
Having Ms set above 16x or 3200ppr is pointless with normal steppers has they won't resolve any hgher than this. It also has a Negative affect on Torque at high speed.
Ms of 8x (1600ppr) is more than good enough for any stepper system using Hybrid steppers and will give reliable stable system. If you want more resolution the either apply a ratio or fit screws with smaller pitch. Trying to Use High Ms will only make your machine unstable and lower peformance.

[uli12us]

I know, that µstepping don't enhance the real resolution. But in the case of an exact circle, it'll enhance the circular form. And maybe I can reach a little bit better fit. with my little Emco, I have only
72 ppr, so i have a minimal distance from 0,0277mm in diametre. Thats a bit big if I want a tight fit for ball bearings or similiar parts.
Thats only, because the normal *4 or *8 µStep brings a bit strange results, that can't display on a
standard XYZ-display of a machine.

[JAZZCNC]

I have only 72 ppr, so i have a minimal distance from 0,0277mm in diametre. Thats a bit big if I want a tight fit for ball bearings or similiar parts.

That's a strange Number for Stepper motor.? That's 5 deg per step.! Are you sure.?

[uli12us]

Yes, thats a 30Year old machine. they used bergerlahr 5fase steppers, with a strange driver as well.
But as long as the machine run without problems, i don't change the control and drive parts of it.
The precision is rather limited, but I don't need often H7 or smaller. In the mill its another thing,
if I want a bore for a bearing, it must be within 1 or 2/100mm. I can't easy grind it to the next tolerance end.

[JAZZCNC]

Yes, thats a 30Year old machine. they used bergerlahr 5fase steppers, with a strange driver as well.

Even stranger then because 5 phase steppers give much lower Step angles due to having 10 poles. This is why they were used because the gave greater resolution and lot smoother running because of smaller rotor steps. They also increase in torque when Ms rather than loose torque like 2 phase steppers do.
The down side being more PPR required compared to 2 phase motor.

The first Smaller leadshine Hybrid Servo motor used 5 phase steppers for this reason. 2Nm Hybrid servo motor gives a 3nm 2 phase motor a run for it's money and is lot smoother.

[Gary]

they were 3 phase actually, leadshine dont make 5 phase drivers.