Ok, I’m trying to calibrate my ooznest OX cnc and I have some question for the community…
I cut a square 100x100 mm and a circle of 50mm diameter.
In the pictures you can see the results.
What should I do to obtain a more precise cut? And what is the best result achievable?
Not sure on your controller but should have adjustment of steps per in or mm this would be adjusted.
You shouldn’t calibrate by cuts. Jog the machine until the gantry is 100mm from the end plate. Then, jog the longest you can before the gantry would hit the other end, and compare the results.
Let’s say you have 100steps/mm in software
You start at 100mm,and tell it to move 600. It stop at 694 (should be 700)
You then do 600/594=1.010 and times that by 100 (old step/mm value) to get 101.01steps/mm. Send that as your $10_ and do another set of jogs to confirm
I used digital caliber by clamping to work surface and let the end of tool push caliber to get accurate measurement. So give command of 100 mm like Julius says but using digital caliber gives you very good measurement. Also mounting precision ruler with fine point tool can work. See these videos
No, 100mm is too small for anything but your Z axis. You can eyeball to 1/4mm with any good ruler, so it’s better to be out by 0.2mm at 800mm then 100mm. Trust me, and thank me later.
Yes it is best to go as far as machine and measurement tool will allow. So on digital caliber it was max of 8" so 200 mm. The longer machine moves will increase accuracy of adjustment as long as you have accurate way to measure machine movement.
Ok thanks for your suggestions, but from my 3D printing experience, adjusting the steps per mm shouldn’t be done… I think that this principle should be valid for every belt/pulley driven machine…
from the reprap wiki calibration page:
http://reprap.org/wiki/Calibration
"X & Y scaling and steps/mm calculations
The following information concerning steps/mm adjustments is outdated. It has since been agreed that steps/mm should be set to the exact calculated values since printing with non-ideal steps/mm results in an accurate test piece, but makes the dimensions on every other part even more inaccurate."
What do you think about it?
I am not sure what inaccuracies this would cause to make sure machine moves distance commanded. Have not seen any issues with adjusting steps from calculated ideal to real world results.
A 3D printed is a seperate machine and different process.
I don’t fully agree with you… the mechanical principle is exactly the same.
Printers are built totally different and don’t require the same precision.
You don’t have a gantry to calibrate from so maybe printing a 100mm line is
enough but it won’t be for a cnc
Hi,
I would advise doing a multiple tests at the maximum travel as explained above. If it is consistently lower by the same amount, then the steps/mm needs adjusting.
Best Regards
Ryan Lock
I personally just configure this with Mach3 which allows me to calibrate each axis and gives me the correct mm setting
