Need Help! Circles not round, 6040 laser machine - Page 4

# Thread: Circles not round, 6040 laser machine

1. ## Re: Circles not round, 6040 laser machine

If you have switched the x y axis completely and the circle "change" (signals x and y simetrical at the end) then i think in a controller problem (maybe a config problem ? steps or some automatic feature in software)
If desactivate backlash compensation and make a square (circle are simetrical too, but the run of axis are diferent, and are equals in a square) ?
Steps of both axis are equal in the config ? the configuration of two drivers are equal ?
Martin.-

2. ## Re: Circles not round, 6040 laser machine

Originally Posted by otromar
If you have switched the x y axis completely and the circle "change" (signals x and y simetrical at the end) then i think in a controller problem (maybe a config problem ? steps or some automatic feature in software)
If desactivate backlash compensation and make a square (circle are simetrical too, but the run of axis are diferent, and are equals in a square) ?
Steps of both axis are equal in the config ? the configuration of two drivers are equal ?
Martin.-
that's the strange thing in all of this, when i make squares the measurements come out the same for the x and y axis but then this happens.. what i did notice today was that when i cut an acrylic circle using black acrylic i am able to see the steps and curious enough, when the distance between steps is greater is when the spike or "ovality" occurs:

as you can see in the pics the lines; where there are many consecutive lines, the arc comes out perfect but when the lines are spaced almost like it's a continuous movement, is where the ovality occurs...

3. ## Re: Circles not round, 6040 laser machine

you mean vertical lines in lateral side ? this marks are because the laser is pulsated, not continuos. I cant see the relation... because the drivers and the lasers "dont know each other". How this lines become espaced ? you increase cut velocity ? you increase diameter of circle ?
A square are perfect ? strange ...
can you draw a circle separated in 4 arcs of 90° each one a bit separated and mark (low power, not cutting) in a acrylic trying to find any other clue ?
Martin.-

4. ## Re: Circles not round, 6040 laser machine

Originally Posted by otromar
you mean vertical lines in lateral side ? this marks are because the laser is pulsated, not continuos. I cant see the relation... because the drivers and the lasers "dont know each other". How this lines become espaced ? you increase cut velocity ? you increase diameter of circle ?
A square are perfect ? strange ...
can you draw a circle separated in 4 arcs of 90° each one a bit separated and mark (low power, not cutting) in a acrylic trying to find any other clue ?
Martin.-
the lines become "espaced" (haha i like the term) without me changing anything, this black acrylic cut piece is one continous piece, i guess it has something to do with microstepping? or the arcs generated by the gcode itself?

hum i have not tried 4 arcs making a circle no, i'll try it tommorrow then and see

i guess i can arrive to an obvious conclusion that the leetro mpc6585 is a bad controller because it does not generate accurate arcs and step possitions nor does it controll microstepping very well

5. ## Re: Circles not round, 6040 laser machine

jejeje i sorry, a mix of spanish and english !!! Before do something with the leetro mpc6585 think in other parts like drivers and motors ...
And all this controllers dont "eat" gcode, a lot of them "eat" a modified code copied from HP plotters (in some cases you copy paste this codes in a plotter simulator and you can see the same draw...)
Martin.-

6. ## Re: Circles not round, 6040 laser machine

Originally Posted by otromar
jejeje i sorry, a mix of spanish and english !!! Before do something with the leetro mpc6585 think in other parts like drivers and motors ...
Martin.-
i have tried everything, it's not mechanical so.. i've tried switching around stepper drivers, i've tried various speeds and accelerations, i have callibrated steps and everything else, i have leveled the machine, i have changed stepper current and microsteps,i have imported circles from outside lasercut, i literally cannot think of anything else other than the controller being a real piece of shnitzel! XD

7. ## Re: Circles not round, 6040 laser machine

Tigox,

Seems like you and I have the EXACT same problem. I can cut anything but a circle fine, etch perfectly, do whatever... I just can't cut a circle for the life of me. I have been over the mechanical properties of this machine 3 times now.... damn thing is level, square, plum, you name it.. its good.

8. ## Re: Circles not round, 6040 laser machine

tigox if you wanna try something else (if you havent done already)

1) if you have done any user menu (on the main window) adjustments (transform, path optimization, backlash appy fix, backlash compensation values etc...) reset them to 0
2) now there is a cut optimization icon (see top toolbar where it says bmp, next to it is a square, third one looks like triangle... thats the one)
3) in cut optimization menu, unselect everything, choose up to bottom in drop down, and set BLOCK HEIGHT to max value (say 300), important no tick box should be selected! and no path optimization in the laser start options...
4) now draw a rectangle 450 mm by 250mm (if you can?, or whatever the max you can do but not the max machine can as it tends to cause problems near edges)
5) measure the rectangle...
6) go to file / vendor settings (password rd8888 or RD8888)
7) click READ on the bottom. select X axis, click "..." menu top right side
8) a window will pop: enter your drawing and measured values for machine to adjust stepper motor (for X axis, 450 is draw size, but measured size will be different, say 449 or 451.. etch)
9) do the same for Y axis as well
10) click WRITE on the bottom menu
11) Draw the same rectangle again, measure again? if you dont have real backlash issue (on the rail, or belts too tight or loose, or anything rubbing/draging etc) your rectangle will close. draw a circle, and it should close as well, but check cut optimization menu, and make sure everything unselected and block value of max or not smaller than your max drawing length in an axis...

I had the similar issues as well, fixed the tensions on Y axis belt, had to adjust stepper motor position on the X axis as its belt was rubbing against the rail when it was going further away from the stepper motor of the X axis... once all backlash issues rectified, and found the block value/cut optimization options by accident, my problems sorted

sort of... as i have tube fading away issue now due to silly chinese using used or bad tubes on shipment... but this is a totally separate issue...

Good luck and report if it works man...

9. Originally Posted by mysticusa
tigox if you wanna try something else (if you havent done already)

1) if you have done any user menu (on the main window) adjustments (transform, path optimization, backlash appy fix, backlash compensation values etc...) reset them to 0
2) now there is a cut optimization icon (see top toolbar where it says bmp, next to it is a square, third one looks like triangle... thats the one)
3) in cut optimization menu, unselect everything, choose up to bottom in drop down, and set BLOCK HEIGHT to max value (say 300), important no tick box should be selected! and no path optimization in the laser start options...
4) now draw a rectangle 450 mm by 250mm (if you can?, or whatever the max you can do but not the max machine can as it tends to cause problems near edges)
5) measure the rectangle...
6) go to file / vendor settings (password rd8888 or RD8888)
7) click READ on the bottom. select X axis, click "..." menu top right side
8) a window will pop: enter your drawing and measured values for machine to adjust stepper motor (for X axis, 450 is draw size, but measured size will be different, say 449 or 451.. etch)
9) do the same for Y axis as well
10) click WRITE on the bottom menu
11) Draw the same rectangle again, measure again? if you dont have real backlash issue (on the rail, or belts too tight or loose, or anything rubbing/draging etc) your rectangle will close. draw a circle, and it should close as well, but check cut optimization menu, and make sure everything unselected and block value of max or not smaller than your max drawing length in an axis...

I had the similar issues as well, fixed the tensions on Y axis belt, had to adjust stepper motor position on the X axis as its belt was rubbing against the rail when it was going further away from the stepper motor of the X axis... once all backlash issues rectified, and found the block value/cut optimization options by accident, my problems sorted

sort of... as i have tube fading away issue now due to silly chinese using used or bad tubes on shipment... but this is a totally separate issue...

Good luck and report if it works man...
I use lasercut :/

10. ## Re: Circles not round, 6040 laser machine

Is there anyone on this forum with insight on the mpc6585? Maybe it's the controller that has poor microstepping capability, I mean, from what I have seen so far, it's a really bad controller with crappy software haha

11. ## Re: Circles not round, 6040 laser machine

I dont know the lasercut software, but what i see/hear they are similar software like laserwork rdwork etc.. just different name with same function, anyways, if it is totally different software, you could check parameters i mentioned... (as long as you dont have hardware issues) everything you do in the software it effects the outcome... like when you add backlash adjustment, it is fine and may work for linear lines, but as soon as you draw circles or round objects, it will amplify / distort your images! anyways,if you dont think you are using similar parameters as i mentioned and software is really difficult to adjust, good luck my friend..

12. ## Re: Circles not round, 6040 laser machine

Tigox,

I updated my thread here with a basic how to, the problem is fixed. I give Mystic all the credit, all I did was tweak it a little. I bet you have the same issue too as our problems were identical.

http://www.cnczone.com/forums/genera...ml#post1872650

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