Nema34 - DM860A Driver & Mach3

[cropwell]

Is this calculation valid even if the pulley on the threaded rod has not been tapped but is held in place by nut-locknut?

Only if the pulley does not slip, and that arrangement looks as if it will do so at some time.

You are only using threaded rod on X and Y as axles, so the pitch is irrelevant.

I have yet to get my head round the X and Y axis arrangements, but it looks like the belt attached to the axis will move 200mm per turn of the axle, but you are geared down 3: or 4:1 depending on the number of teeth on your drive pulley. So if you are using 15T drive then your resolution is 4 steps per mm or if 20T 3 steps/mm. So I can see why you are hoping to get some positional accuracy using microstepping to increase your resolution.

I have doubts that this current design will be very accurate. You should also look at some way of fixing your pulleys to the axles other than locking nuts, are there no grubscrew holes on the pulleys ?

[Channel]

Hello,

First of all, thanks for the answers I understood more in these two days than in a month of homemade research.

Let's start with order:

I counted the teeth on the motor pulley (X & Y axis) and is 15 teeth

On the engine pulleys there are two grubscrews and two "footprints" on the shaft, so as to make everything more stable.

As for the pulleys on the threaded bars the nuts and lock nuts that hold everything are stopped with the threadlocker (like the loctite) and also here they should not go anywhere.

As for precision as a first mention the project was bought so I'm pretty sure it should go (unless of my assembly errors)

There is also a video that shows how it works on youtube, and as I said its author is mentioned a couple of times in this forum or Mirko slepko ...

Tomorrow I will try to set the values for the Z axis in order to verify the behavior ...

[Channel]

Hi all!

today I counted the teeth of the pulleys of the Z axis and both result from 20 teeth.

So I applied the formula suggested by cropwell using the value of drivers 8.

(20/20) * 1.5 = 1.5 >> 200 / 1.5 = 133.333 >>> 133.33X 8 = 1066.66

So I set this value in the Z axis.

By moving the axis, however, I noticed that it still moved in an inaccurate way.

So I used the "Auto-tuning" tool from mach3 which calibrated the steps to 533.33 (exactly half)

I have tested some movements such as

- G1 Z10 F400
- G1 Z0 F400
- G1 Z-30 F400
- G0 Z0 F400

And all the movements were performed correctly. (and to be honest, I' am REALLY HAPPY)

The only thing I would like to know because I have this difference between the steps that the machine has calculated and those instead obtained by formula.

I'm pretty sure the driver is at 8 and not at 4 (setting that would justify 533.33 as a step value) but tomorrow I will recheck. XD

As for the X & Y axes, maybe this is the formula?

(engine step * (driven pulley / driving pulley) * driver value) / 50mm

The 50mm value I obtained by making a complete turn to the 60-tooth pulley and measuring the displacement of the trolley.

So the calculation would remain ...
(200 (60/15) x8) / 50 >> (200x4x8) / 50 >>> 6400/50 = 128.

Is this value the one I have to set in the motor tuning section for the X & Y axes?

Thanks all again for your precious help