CNC Laser Shaking when Changing Directions Rapidly.

[Brandon Bonenfant]

Hey everyone,

So I managed to adjust the settings and got the cuts a ton better! There was still a bit of play, but not nearly as much as before.

So I ran a test plate of a bunch of circles and the first plate went flawlessly........

but then.....

The second plate started great and then did almost exactly what Kev Williams' machine did!!!! So it looks as if there is an issue with the Y-Axis Wiring!!!!!!!

I'm really hoping this will help alleviate the remaining issues I am seeing.

I ripped apart the drag chain and did not see any visible damage on the Y-Stepper Motor Wire, nor did I see any issues when tracing it back to the control panel and power connections. This problem seems to happen more and more as I run the machine, but I cannot find the tear!

Does anyone have any tips / tricks on finding the issue with the wiring without straight replacing the entire wire?

Thanks so much for everyone's help so far!

- Brandon

[Kev Williams]

On my machine, they used off-the-shelf "Instar" steppers- nothing at all wrong with them- but they come with wiring that's too short, so Triumph just added to the wires. How I figured out where to look was because I finally noticed the machine always messed up at around 16 to 18 inches down in the Y axis, so I slewed the gantry down 17" and started pulling the chain apart, and where the wires were spliced was just going up into the loop. I slewed back up towards the top, and fiddled with the wires, and sure enough, it would go nuts every time I fiddled... The wiring LOOKED FINE, I had to remove nearly all the chain clips(?) so I could pull the wires out and apart, and that's when I found the black wire drooping in the middle. The solder joint broke, but worked fine as long as the wires laid flat...

SO, check for butt splices in your stepper wires. Also, check where the wires run thru the cabinet, could be a wire is against a hole with a sharp edge, it wouldn't take many trips back n forth with a little tension on the wires to cut into the insulation and short the wire to the cabinet...

FWIW, after I fixed mine the first time it did it again about 4 months later- solder don't bend! Second repair, IIRC I just hand twisted the wires for about an inch and finished with heat shrink tubing.

And-- when the LS900 started doing the same thing, I knew exactly what it was! And the machine showed me where the problem was as the wire was arcing off the cabinet, bright sparks are easy to see! Those wires weren't spliced, the ground wire I assume deals with the most heat, and I suspect the insulation wore itself down rubbing against the chain...

Good luck with it, I really hope you don't have to send it back!

[John Lifer]

I'm stepping in and saying if it looks to be the Y axis only, then get replacement wires out, cut and installed.

I've a cheap 3d printer I bought and put together a couple of months back. Super fine wires on the darn thing. 26 gauge max on most of the thing, some 30 or smaller. Added drag link run on the x axis and within a week, was having issues with fan stopping. Replaced wires, all the way as I could get close, but wire was broken inside insulation and no apparent damage. Same thing for heating cable a few days later. Replaced that one and changed up the links a bit, so far no further issues. So if you think it's wiring, You might spend a little time trying to find, but I'd spend the effort on just replacing.

(Yeah, it will be a pain) But at least you think you might have solved it.

[Bill George]

As a former air craft electrician I can tell you solder for splicing wires that flex went away eons ago. All we used was good grade Mil Spec crimp on splices and terminal connectors. It was crimped twice, once for the wire and the other for the wire covered insulation. Some of the commercial grade crimping tools did it all in one operation. T&B brand is one I try to buy now as they are the closest to Mil Spec.

[Brandon Bonenfant]

Thanks everyone,

The wiring issue seems to be fixed now. I ended up spending a bit of time looking for the issue and ended up replacing the entire line like mentioned above. They had 4 spots where the wire was solder from the stepper motor to the control board. Seemed like they built it is steps and used small pieces of wires. I ended up getting replacement wire from the local hardware store and replaced the run with a single pieced and crimped and heat shrank it together. Seems to be working well for the last 4-5 hours!

There is still some issues with the shaking, but I'm currently messing with belt tensions and such to try and alleviate this as much as I can. I'm getting very very close to having it running perfectly!

Thank you all so much for everything! This really is an amazing community of people!!!

I'll try to post some before / after pictures of the cuts once I have it squared away completely!

-Brandon