Heya, so i have a creality rotary chuck pro, standard omtech k40 with a newly installed MG3 controller.
Trying to set this up like i had it beforehand and i just cant seem to get it right.
Firstly and my main issue - the Y axis(the rotary) spins at a much faster speed than the x axis.
Ive narrowed my mm per rotation down to 20.5, my object diameter is roughly 85mm.
The square shown in the video is 30x30mm. And usually comes out perfect in terms of size.
Is it acceleration based? I cant figure it out.
Also that should have been 2 squares directly on top of one another. Is there any settings that would cause is not to rotate back properly, or that a hardware problem?
When i change the $1 setting to 255, and leave the motors energised, the rotary has about a 15 degree ‘free play’ before the energised motor stops it turning anymore.
I noticed this too when attached to the SF-A9 laser. I first thought the 255-thing was not working. I don’t think my S30 Pro did this. I am curious if this is normal, or common.
xTool RA2 Rotary.
Sculpfun S30 Pro and SF-A9 lasers.
Yes, I had to set the steps per mm so Test would give exactly 1 revolution and return. I set it on the S30 and it was correct for the A9. Don’t remember exactly, but mine was something like 163mm for the chuck setup. Yours could be anything if it is not the xTool RA2 Pro.
I think the typical Y stepper is 80mm/rotation, so you can start there. Remember this is for the Chuck. When I click on Roller, it shows 77mm roller diameter, which is way wrong. The roller is something like 13mm, and it looks like you can put that in and then switch back and forth. But do not trust me on this. Test for yourself.
That makes it sound like 80mm, or very close, is the magic number for mm/rotation. Oops! 40mm = 2 rotations? You have the Chuck button selected? 20mm/rotation is very unlikely.
The rotary is really Yaxis travel, so imagine it flattened out. In theory, a square 80mm high should make a single line on one side, assuming the mm/rotation and your cylinder circumfrence is 80mm. In theory.
Don’t forget to allow for the additional diameter of the tape. A .5mm thick masking tape will add 3+/- mm to the circumfrence.
I noticed in the video your Yaxis lines seem to not burn. If this is true, examine your GRBL $$ parameters using the Console window. The X and Y parameters should be equal. The X-Y parameter pairs are:
100,101 step, mm
110, 111 max rate mm/sec
120, 121 accel mm/sec^2
Due to the extra mass of the gantry, Y should never be larger than the X value.
To test if X & Y are syncronized, burn a 45° diagonal line on the rotating part. Any error will be obvious.
One advantage of the chuck over rollers is that you can use higher velocities. But common sense is the rule.
I have triple checked this, and from what i can tell, its almost exactly 20mm, from everything i read online this is excessively small, however its all i can gather that works
I was testing today, i can burn a full size/filled in image, however i must burn from one end to the other with no changes in spin direction otherwise the image jumps around.
I also noticed that when i click move 1mm on the Y axis it works within the ‘ratio’ of what it should for 1mm, but every 3rd or 4th move command, it moves a lot more.
Excuse the essay, i will get a video of this sometime tomorrow after work.
They do burn, but it moves so quick that its faint. If i try to burn the square quicker than say 70mm/s, the square is no longer a square!
Will definitely try this, cant believe i hadnt thought of that before
Not on my watch. I welcome additional help because I learn from that too. When you present something not mentioned yet, that is a win for everybody. Like was said in the Jodie Foster movie Contact, “No opinions will be suppressed here today.”
