Y-axis does not move... as soon the laser fires. but is fine before, or after restart

[Pete Cyr]

by sebastien laforet » Wed Sep 07, 2016 3:37 am

hello everybody,

i'm currently setting up a Bodor machine (chinese, with RDWorks) and i have a strange problem. i can use the LCD panel to move the X, Y and Z axis just fine. the display shows the correct position and updates correctly when moving the head with the arrows.

then, i set the origin, choose a job, click "frame", and the head just moves around the cutting area. fine. both x and y directions are ok.

i launch the job : x and y move up to the start point, laser ignites and then only the X-axis is moving. so, all i get is an horizontal line, but the lcd display is ok : the cross follows the cutting pattern along both axis, and the coordinates are moving, exactly as if the y-axis was working.

after that, the y-axis is definitely dead : if i use the arrows, the display changes coordinates, but it won't move. resetting the axis origin doesn't work either, since the head does not move the process never ends.

after a full stop and restart of the machine, the y-axis works.. until the laser fires!

if i just "pulse", it is sufficient to break the y-axis, and it won't work again until complete stop!

but i have been able to complete some drawings correctly after a long pause.. one is ok, 2nd changing power/speed value, still ok, 3rd KO and then all are failed. i have not have time to redo a full "sleep" of the machine then test, but i might (maybe) work.

any idea? it seems there is no error message either on the LCD or in RDWorks, the machine just doesn't move along the y-axis while currently believing it is (following correctly the pattern when cutting, and changing y-coordinate when moving with arrows).
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Post by sebastien laforet » Thu Sep 08, 2016 7:09 pm

update after some new tests.

startup of the machine : everything ok, x, y and z motor working, with green led on their control board.

"pulse" --> immediately, all 3 motors are dead, each with a blinking red led on their board.

for each motor, i unplug the power from the card, replug, they live again, and they are responding to the main control (move with arrows)

same when directly sending a job : as soon as the laser ignites, at least one motor is out (mostly y and z).


i have finally been able to have something working : i send a job with no more than 10% power : at this setting, the laser does NOT start, and the motors don't have any problem. then, slowly upping the power, 12, 15, ... 25%. and bam! now it works.

in each program, i have included a very small cut at about 12%, with first priority, and so far i have been able to cut with up to 60% power without botching the motors

my conclusion : there must be some bad backlash between the laser power supply and the motors power supply and/or motherboard, and the initial surge on a not "warmed" laser botches everything.
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Post by Gene Uselman » Fri Sep 09, 2016 7:55 am

Keith and Schlaf- I am experiencing the same problem, and as I said in one of your other posts, the 36v power supply (which powers the steppers and the stepper drivers died. I had to send Bodor a video of me testing the PS with a meter, but they did send a new one promptly. And I have both machine grounded to a copper rod driven thru a hole in the cement floor BTW. Gene
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Post by sebastien laforet » Tue Sep 13, 2016 2:21 am

some more news after more tests... below is the copy of the mail i sent to tech support. after first tests, they asked me to remove the frame cover on the right side (anode of the laser). definitely not the most secure thing to do, but it was necessary "for the sake of science".

---------------------------------

yesterday i have made some tests after removing the cover. that's definitely better, but still not perfect.

at startup :

- pulse, ok, motors are NOT frozen, can move with the arrows.

- try a job with medium power, job stops at laser ignition, BUT the motor cards are NOT blinking red (they were when the cover was on), and if i hit "reset", the job is correctly interrupted and the motors are working to set the head at 0/0 then return to "origin" position.

--> definitely, it seems there is less interference. still enough to disturb, but not fry the motor controller cards. i don't need to hard-reset the machine if the job stops.

after that, i did as before : some job with some start line at 10% power, then some with 18%, then 30% or more... in this case, it works fine. the key seems to be to start with low level power and ramp-up.

and later, when the machine have been lasering for some time, it seems i can directly start jobs with some cutting power, and it works.

--> so, maybe the PSU has some problem at startup and works fine when it is "warm" enough...

also, at a moment, i had an error "power 1 open circuit fault Please check the power output circuit". might be related or not. message disappeared after a hard reset and after that the machine was working without this error anymore.
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Post by sebastien laforet » Fri Sep 16, 2016 2:56 am

update from yesterday test...

started the machine. let warm 5mn. have a startup job with some circles at 10, 12, 15, 18, 25% power is this order. start the job. everything fine.

some more jobs, with marking and cutting, so 18% and 50+%. still nice.

make some tuning of mirrors, pulsing. still working like a charm. have nevertheless to decrease max power seriously, cause paper gets burned (1cm diameter) instantly at max 70%...

nows some serious cutting, with 80% power only. works! does not even need to add a small cut at low power in the start of the job.

seriously, now it "just works"... quite mysterious.
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Post by sebastien laforet » Tue Oct 04, 2016 2:40 am




ronh wrote:
Solution 1: Completely isolated the cathode wire with additional insulation
Solution 2: isolate the anode lead from all control wiring. The anode lead passed through a small hole in the laser platform along side the Y stepper motor lead. Both leads were squeezed through the same hole. this is weird, since for the exact same problem i did not get quite the same answers...

for me, the suggestion was :
- remove the cover frame on the anode (just this corrected everything)
- make sure the anode lead and water pipe do not touch the cover (when the cover is back on)

there was no suggestion to use the silicon tape to enhance isolation (even if a roll is provided with the machine, with no more explanation) or to alter the path of the anod lead.

since i'm a computer guy and firmly believe in "if it works, don't touch anything", i am still with my frame cover removed and the machine working. someday, when i feel lucky i'll try to put the cover again and check how it works.
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Post by Gene Uselman » Tue Oct 04, 2016 7:47 am

I just received the second identical machine last week and unpacked this weekend. Measuring where the laser tube comes out of the side of the chassis this on is going to have the same problem with the extension housing being way offset from where it should be. On the first one I had to cut away part of the flange of the extension weldment- and I will have to on this one as well. The tape that was provided I think is supposed to be high voltage fuseable tape- but it does not even stick to it self.

tube%20extension.jpg

Sebastien- I would not feel comfortable here with people carrying things around with the tube unprotected- not to mention that the hot side of the tube is exposed like a giant Van de Graff generator. In high school we charged one up and when the teacher walked by- ZAPPP.

Ron- I have not operated enough to get your Laser 1 error, yet. Gene
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