when I create a flat project it generates x and y and perfect central position.
if you activate the rotating roller or spindle, the positions are significantly staggered.
then the dimensions are significantly altered as is the starting point on the y axis.
It’s not a roller configuration problem but a problem that I can’t understand the cause of.
It is clear that I expected a variation in the size of the y axis based on the variation in the cm traveled in the rotation, but this is not the case
Thank you
That depends on the setting of the $102 parameter. If you changed it for the rotary, you will have to change it back. I admit yours is a big difference. Did you check the $101 parameter?
No grbl code !!!
I use marlin.
In may opinion the problem is bug in lightburn.
Do the tests and see that there is a problem with the program.
just look at the data generated by the program, it is not a machine setting
I did, before I replied. I set the steps in the Rotary window to 60 where it should have been 80 and the Yaxis travel was les than it should have been. I generated GCode for both Rotary off and on to see what would happen.
Using a chuck or rollers makes a difference too. The numbers you posted suggest a roller rotary.
No idea how you can fix it on a Marlin controller.
Lightburn id not broke. If it was, there would be easily 30+ complaint postings by now.
the problem is present when I enable the rotor and save the gcode generated by lightburn on memory.
once the memory is inserted and printing is started, the y-axis carriage goes out of range
(see image y marked in red)
if I remove the activation of the rotor the gcode generated starts from the center.
clearly it is deformed because the y axis does not respect
the diameter of the object.
therefore lightburn outputs an incorrect calculation when the rotor is activated.
from out-of-range y-axis positions and amplitudes
the steps/mm can be adjusted from the peripheral menu.
let’s say that I temporarily solved it by disabling the rotor and calculating the motor steps on each diameter.
the cup is approximately 82.5mm
by formula
steps = 3200/(how many mm the lathe travels in one engine revolution)
3200/66.5mm=48 steps
at this point I change the original steps 80 to 48
by command M92 Y48 and the print is perfect.
it would be enough for light burn to generate the command grbl $ or marlin M92 Y–
and insert it into the Gcode file.
or they should check why by activating the rotor the y coordinate data is incorrect.
so I repeat that in my opinion it is an algorithm error
used.
How is Lightburn supposed to know the steps for the rotary is 48 and not 80? It cannot unless you put that in the Rotary Setup window. I did not follow your math (you pulled 66.5 out of the air), but you have determined the correct value to use.
Not everybody has a Marlin, and not everybody has the same rotary as you. And nearly nobody has the problem you are experiencing, once they understand their part in setting up the rotary.
My rotaries (I have a chuck and roller one) are made by different manufacturers. How is a Lightburn “algorithm” supposed to know which one is hooked up? It cannot be determined through that 6-pin plug.
My Solution: I have created a Macro to set the GRBL parameters I need for the Rotary.
Your Solution:Somebody with a Marlin controller will have to help me here. I have no idea if Lightburn’s Macro or Custom GCode will work for that controller.
if you use lightburn and tell them to engrave a project on the plane everything is perfect and you see it in the generated g-code file.
when you insert/activate the spindle the generated g-code is totally off center!!!
if I have a 500x720 machine when I develop a project and place it in the center the g -code generated by lightburn is normally in the center.
x500/2=250
y720/2=360
if I insert a square in the center of 50mm the gcode
will move x and y by 25mm then the result will be
x250±25 min 225 max 275
y360±25 min 335 max 385
if you look at the output g-code generated by lightburn
And:
ymax 594 ymin 517
with difference and 77mm
the y should start
± 38.5 compared to the center:
360-38.5= ymin 321.5
360+38.5=ymax 398.5
y321 min to y max 398
so I repeat it is not a problem of the machine interface commands or macros of grbl or marlin
since the calculations generated by lightburn inserted the function
rotor are incorrect (see gcode) I opted for a temporary solution:
based on the diameter of the object I calculate the steps/mm to assign to the motor to advance the y axis
correctly.
the 66.5 mm indicated and the distance traveled by the external part of the bowl with 1 revolution of the stepper motor.
this calculation should be done by the lathe function inserted in the program by entering the right diameter.
For now I have solved it this way, I hope that what I say is checked and someone fixes it or gives me a logical solution.
mathematics is not an opinion, if you don’t understand the data entered, get help from a good person.
After the updates I thought they fixed the problems.
by inserting the rotor and changing the diameter of the cup the generated g-code has the y coordinates off center of the work surface.
the center of the surface must always be the same regardless of the diameter of the cup.
It is easily calculated by creating a 50x50 mm test square and reading the gcode
generated by the machine.
as regards the coordinates of (x) everything is ok,
for the coordinates of the (y) are outside the center
(ymax - ymin)/2+ymin = y center
I’ll continue for now
excluding the rotor and manually calculating for each diameter how many steps the motor must take.
these are the 2 files generated by lightburn without rotor and the other with rotor.
how can you
seeing the y axis makes the cup spin off center because the same is generated wrong
if you then change the diameter of the cup to be engraved, the center of the plate changes.
practically the center changes based on the diameter
try generating a job yourself
as simple as a square and save the gcode thus generated. one without rotor and one file with rotor enabled,
you’ll see it’s chaos
the size of the table is visible in the photo at the top left which indicates central coordinates, the problem is generated by light burn and is not a machine problem!!!
nor even marlin.
If you look at the calculations you will see that y is generated with the rotor enabled and off center.
If I start the gcode thus generated, the cup spins more and the handle hits the laser.
I don’t use grbl, I use the PC connected to the machine,
I don’t disable the end stops, and I don’t position the laser in the center manually.
my car knows and uses
the x and y coordinates
real,
it positions itself at the center of the rotor respecting the machine center and switches the y-axis movement motor with that of the rotor automatically.
I use a memory to transfer the gcode to the machine, if the gcode is wrong the machine works incorrectly.
It doesn’t take much to understand my problem.
try to make a project with a square with absolute coordinates, the generated gcode has the y coordinates off center
