During the calibration process using the chain to measure the distance between the motors, Ground Control gives me a distance of 2846.81mm. The same distance with a tape measure gives me 3176mm.
I’ve done the calibration twice. I think I’m following the correct path.
Starting with first link of the left chain on the top tooth of the left motor, hanging down off the left side of that sprocket. Bottom feed - ‘Extend’ the chain from the left motor across to the right motor then ‘Pull it tight’ before clicking ‘Measure’.
This means Ground Control is 329.19mm (12.95inches) short!
What am I doing wrong? Thanks!
I’m not an expert, but the distance per rotation might be a clue. In the groundcontrol.ini -> distperrot = 63.5. You could use the ‘set sprocket to 12’ from the calibration to rotate a full turn and measure the chain feed.
My chain stretches at least 3mm on the ‘pull tight’. I have a 2x4 as top mounted the same way you did and after making it “rock solid” it still flexes 2mm. My motor mounts don’t flex after I modified the mounting. I would expect yours to flex a few mm. That all only would add up to max 10mm and not to the amount you are seeing.
The menus in Kivy aren’t as clear as they should be…
To the right of the word ‘Actions’ is ‘Settings’. Once that is clicked, ‘Maslow Settings’ comes up. Now click on the words ‘Maslow Settings’ to see a dropdown list of other settings pages - ‘Advanced Settingsd’ is there.
measure with the tape measure while it’s under load, I’ll bet that you see a air
amount of flex at that time compared to measureing while it’s slack. I expect
that those mounts will flex more than you think
but a difference of 300mm is insane, that’s a foot of difference
check what it reports before you do the calibration calculation, I think the
calibration routine will adjust the motor spacing value to try and make the math
work out, and that’s clearly very wrong in your case.
@blurfl got me squared away however after I’m still coming up short using the chain to measure. Ground control measures to 3130mm. Tape measure gives me 3176mm.
I got fed up and now trying manual calibration with inaccuracies still.
What I have observed, is that the machine is pretty good at hitting the geometric center of the 4x8 plywood sheet after the last step (when you put in the distances between the cuts).
I drew a grid on the plywood before starting and have “sent it manually” to many of the intersections. It gets there and gets back “home” just fine.
