calibrating?

Just a question for the future as I am in full user/learner mode now not developer mode.

Is there a way to calibrate how far the axis move to so many pulses? This way when I build the bighandi or what ever and it uses a slightly different drive setup it can still work right? Hidden in the ini file perhaps?

Hi Mark,

Yes ... absolutely. In OpenSBP code, that number is called the "Unit Value" and is set with the [VU] Command. For a Handibot it is 4000, meaning there are 4000 steps per inch. There will be several different ways to set it in the new FabMo system.

Ted Hall, ShopBot Tools

That is great. I just failed to find it looking through the commands. That pretty well guarantees that if I build a gantry machine it will have Handibot guts as well as other parts.

Ted Hall, ShopBot Wrote:
-------------------------------------------------------
> Hi Mark,
>
> Yes ... absolutely. In OpenSBP code, that number
> is called the "Unit Value" and is set with the
> [VU] Command. For a Handibot it is 4000, meaning
> there are 4000 steps per inch. There will be
> several different ways to set it in the new FabMo
> system.
>
> Ted Hall, ShopBot Tools

Deleted by OP



Edited 1 time(s). Last edit at 12/10/2016 04:23PM by gclayton.

Deleted by OP.



Edited 6 time(s). Last edit at 12/10/2016 04:22PM by gclayton.

Hi Ted,

I carved a mm ruler with my Handibot into 6x8" acrylic sheet. It looks great. I carved one in the vertical direction with lines every mm, and one in the horizontal direction.
For the Y, it is bang on the whole 8" or 210mm.
But for the X, it is off (compared to several metal rules I have) by about 0.5mm by the time it gets to 140mm from the origin. ~0.4% error. Not acceptable if you are making rulers that you would like to be useful.

I think this may explain some artefacts I always get when I do tiling.
Is there a way I can adjust the "steps per inch" (or per mm or cm) in Fabmo?
Or otherwise calibrate X travel?
I assume the VU command you mentioned is in the G-code. Or is there some other way to invoke it and save that result so that the
Handibot always moves in X the number of mm I command it to move?

Thanks,
Steve

that quantity is referred to as the "Unit Value" and is set with the [VU] Command. For a Handibot it is 4000, that means there are 4000 steps per inch. There will be a number of distinct approaches to set it in the new FabMo system.