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Brad Patturelli
05-12-2017, 9:40 AM
I'm pretty sure I meant X axis (Left to right motion). I was/am on little sleep.

I setup my material on the bed, set the origin of the laser head to the center of the material, focus and then run job. After any amount of time at some point I hear a little noise, not even disturbing ( maybe a stepper noise, hard to describe) and the laser is off center to the right a few inches, it just keeps lasering away and ruining my piece. When I power the machine off and on, it homes itself but instead of returning to the origin I set in the middle of the material (or the off skew one to the right of center) its now to the left of the original origin I set in middle of material. Any ideas on what would cause this?

I have checked and tightened belts, checked for any screws loose (besides me).

I was running at 400mm/sec

Bill George
05-12-2017, 9:56 AM
Check ALL your wire terminal connections with a screwdriver. You will find a few loose, that is what I found on mine anyway when I had my G.Weike back in 2014.

Brad Patturelli
05-12-2017, 2:46 PM
Thank you. I did check after I received the machine and your right there was loose wires then. I rechecked them today and all were tight.
I did rerun the job on test material at 200mm/sec and it didn't lose it's zero and came out great. Hesitant to run it on my plaque though.

Bill George
05-12-2017, 3:33 PM
Thank you. I did check after I received the machine and your right there was loose wires then. I rechecked them today and all were tight.
I did rerun the job on test material at 200mm/sec and it didn't lose it's zero and came out great. Hesitant to run it on my plaque though.
Did you check where they spliced the wires to the stepper motors inside the wire harness?

Brad Patturelli
05-12-2017, 5:17 PM
Did you check where they spliced the wires to the stepper motors inside the wire harness?

I'm pretty sure I meant X axis (Left to right motion). thanks again, I followed the wires from stepper motor to the stepper driver (i think thats what its called) and did not see any splices. Do you think its a wiring or something mechanical making it lose steps at the 400mm/sec speed or something like that? I don't think that's very fast, maybe someone smarter than me and with more sleep can tell me.

Bill George
05-12-2017, 7:07 PM
I'm pretty sure I meant X axis (Left to right motion). thanks again, I followed the wires from stepper motor to the stepper driver (i think thats what its called) and did not see any splices. Do you think its a wiring or something mechanical making it lose steps at the 400mm/sec speed or something like that? I don't think that's very fast, maybe someone smarter than me and with more sleep can tell me.

Losing steps? Slow it down to 300 and see what happens. Could also be a power supply issue to the motor driver.

Rich Harman
05-14-2017, 1:45 AM
Belts too tight could cause it to lose steps. Make sure the rails are clean and lubed.

Is this a new problem? Have you been engraving at 400mm/s or more in the past without issues?

Kev Williams
05-14-2017, 2:10 AM
These are the splices Bill's talking about. My Triumph went thru this.
Your problem may caused by something else, but you should examine the wires within your drag chains for splices.

Pic 1 is where I found my splices, within the Y chain, these are the X stepper wires...
Pic 2 is where the splices would roll up in the chain, which exactly in the Y coordinates where all the fun happened...
Pic 3 shows the ground wire basically broke in half.
360176360177360178

The machined worked fine when the wires were laying flat, even on top of the chain after rolling up and around.
But while in the arc, the wire would lose contact...

Was an easy fix, I re-soldered the connection, new shrink wrap, and then I carefully pre-bent the wires & splices
so they'd roll up the arc with less stress. Haven't had a problem since.

Triumph was quite appreciative of me figuring this out, they kept giving me the standard 'try this' remedies,
to no avail. Against their advice, I bought a new stepper motor. They were right, that wasn't it! But now I have a spare! ;)
But they also had another customer in Mexico with the same problem as me, and they hadn't found the problem.
Turned out other machine also had a broken spliced wire...