Calibration issues, advice needed

[Kernow Jim]

Hi Jazz

It is a direct drive to all ballscrews. The 'steps per' figures of 637.8, 631.1 and 642.6 on x,y and z respectively was by doing the axis calibration within mach. That is the figures that was coming on the dialogue box 'do you accept these settings'

Armed with my new knowledge from yourself and Neale, I was proposing to set the MS drivers to 800 steps and type into the 'steps per' box 320, and increase the velocity to 4000 and the acceleration to 1000. Unless you advise against it

My visit to the workshop yesterday, when I changed the velocity and acceleration settings certainly made a huge difference to the jogging and rapid speeds. Yesterday I also changed the MSteps from 800 to 1600 but this made the motors more whinier (is that a word?) more noisy. My machine is housed in my Fathers workshop at the moment, for the purpose of building it (more tools and equipment) which is about 14 miles away. It will be better when I have finished the build and bring home to my smaller less equipped workshop, so I can't exactly nip out to change some settings and report back.

Thanks again Jazz

Jim

[JAZZCNC]

Armed with my new knowledge from yourself and Neale, I was proposing to set the MS drivers to 800 steps and type into the 'steps per' box 320, and increase the velocity to 4000 and the acceleration to 1000. Unless you advise against it

No remember it's a simple a formula to find the Steps per. Divide the Micro steps by the Pitch. . . .So 800/5=160

This is an absolute calculation to within fractions of the calculated figure so when doing the Axis calibration it should be very very close if not the same has the calculated figure. If it's different by a lot then something is wrong.

Things that can cause this differance are the drives micro stepping not being set to what they say they are.?? . . Doesn't happen often but it does happen. (Or you are setting them wrong.!. . It's Common to mix up ON / OFF on Dip switches.?? )

Regards Velocity and Accelleration then you'll just have to play about has every machine is different. 5000 and 800 for X & Y shouldn't be too taxing if you have decent amount of volts on the motors. Slightly less on the Z axis.

[Kernow Jim]

No remember it's a simple a formula to find the Steps per. Divide the Micro steps by the Pitch. . . .So 800/5=160

This is an absolute calculation to within fractions of the calculated figure so when doing the Axis calibration it should be very very close if not the same has the calculated figure. If it's different by a lot then something is wrong.

Things that can cause this differance are the drives micro stepping not being set to what they say they are.?? . . Doesn't happen often but it does happen. (Or you are setting them wrong.!. . It's Common to mix up ON / OFF on Dip switches.?? )

Regards Velocity and Accelleration then you'll just have to play about has every machine is different. 5000 and 800 for X & Y shouldn't be too taxing if you have decent amount of volts on the motors. Slightly less on the Z axis.

Hi Jazz

You were absolutely right, something was wrong. As luck would have it I forgot my disk with the documentation regarding MS driver settings chart. I had to resort to removing a driver from my control box to look at the chart on there. Lo and behold, it seems I have the wrong docs for my drivers. The dip switch settings I have been putting in, eg, 1600 steps has been actually 3200, hence when I calibrated in Mach I was getting a figure of around 640 'steps per'.

I have now set the MS drivers to 1600, manually typed in the 'steps per' box 320. I played around with the velocity and acceleration settings and have ended up at 3000 and 800 respectfully on all three axes.

Everything seems to be running better now.

I don't know how long I would have gone on before making the discovery, good fortune has intervened by me forgetting the document disk, but it has been your insistence that something was wrong that has pushed me on to check and re-check settings.

Thank you again Jazz for your patience and knowledge for a greenhorn.

Jim

[JAZZCNC]

Thank you again Jazz for your patience and knowledge for a greenhorn.

No problem just pleased you found it and sorry if I was blunt.!!

If your happy with those speeds then great and the 1600MS should give you nice smooth running motors but if you do want a little more speed then try at 800 and you should push it up around the 5000mm/min or higher.

What voltage are you running the drives on.?

[Kernow Jim]

Hi Jazz

The drivers are running on 36v, but I have the dip switch set to half power. When I was testing the motors they seemed to get quite hot at standstill with the holding torque when the drivers were on full power. I haven't changed them back.

One other question regarding settings in Mach, in the motor tuning the settings for step pulse and direction pulse (1 to 5) I have set to 2 in both boxes from my documentation. A tutorial video on you tube suggested that these are normally set to 0, any suggestions/recommendations?

Thanks

Jim

[JAZZCNC]

One other question regarding settings in Mach, in the motor tuning the settings for step pulse and direction pulse (1 to 5) I have set to 2 in both boxes from my documentation. A tutorial video on you tube suggested that these are normally set to 0, any suggestions/recommendations

Depends really on your drives so If your manual says 2 then leave it set at that. If you don't know what to set at then just set the Dir slightly higher than Step so 2 & 5 or 0-5.

[Kernow Jim]

Thanks Jazz, I will leave them set as they are as things are running OK.

Thanks again for all your help and advice.

Jim