Laserboard problems with speed and arcing power connector

Machine: K40 upgraded to 60W
Board: Laserboard
Firmware: Smoothie

So here is my dilemma. the power connector is arcing severely on any fast moves sending machine into fault. I have tried various methods to secure it but the socket is just too loose.
I would attempt to tighten the ground contact inside but I won’t in case they want the board back.

Also the board has stopped responding to F rate commands. Machine was cutting at a rate of 20 when it took off at a rate similar to 100 or even faster. There aren’t even any scorch marks from the cut. The only way to get it to cut near that rate is to set it to feed rate of 1 or even .5

I checked the firmware on the SD. It was fine but I replaced it with a new copy just in case. Only changes I made to the file were board size and slowing the fast move speed as per Cohesions instructions.

Has anyone else seen this or know of a workaround? TY in advance.

Please provide pictures of your board, machine, and wiring. I’ll also need a clear description of what the arcing is between. We’ll start there.

Ty Ray, With all the problems you have up there right now this is much appreciated.

So the arcing is between the ground side of the cable connector and the inside of the on board connector. Even though TTL is quite forgiving, this is a rather large arc and it does fault the controller when it occurs. It’s like the connector is being unplugged and plugged back in again without sufficient time for the caps to discharge.

I also again tried new source files to correct the feed issue, this time with formatting the SD to no avail. Machine still thinks it’s Andretti on a bad day.

In these pics I can’t see how the DC Barrel plug is connected to the jack on the board, and I can’t quite imagine the exact arcing symptom you describe, so I’m going to show you and you’re going to tell me what looks familiar.

In the picture there, the plug is not fully inserted into the jack. There should be much less metal exposed.
In this topic, the issue was that the laser return, I think, was actually through the chassis and grounding through that area back to the wall through the LaserBoard’s power supply. Fun!

There is a separate question we frequently get asked which is about sparks when plugging the DC connector into the board which is just due to inrush current, is normal, and only lasts a moment while inserting the connector. Your issue does not sound like that. It sounds like you may have the same issue as the other guy in the topic I linked above.

TY Ray, i am familiar with the in current arc from inserting the plug. The plug is fully installed, however that is not my biggest issue. My biggest issue is the sudden super speed from the steppers.

As I stated earlier, While running a cut, speed set to 20, which worked very well for 2 weeks, The Laser head took off at very high speed. So fast infact that the laser didn’t even have time to leave scorch marks and the cut line was razor thin.

I believed this issue was tied to the arcing problem, which I solved yesterday evening. I believe the board arcing and constantly going into fault has caused something to go wrong. I can only get the machine to cut with speed set to 1 or .5. The files on the card have been replaced with fresh copies of both files with only the bed size information being adjusted. Oh and the default feed rate lowered to 4000.

The board is not responding properly to F code commands.

The problem of the arcing was indeed insertion arcing, but not from the plug being to far out. The socket contact was pushed back into the housing causing random open circuit conditions on fast move vibrations. A light adjustment and the problem went away but the speed issue remains.

Ty for bearing with me on this.

It might help me understand better if you used simple words to explain - you can talk to me like I’m a 5th grader and I won’t be offended in the slightest.

You could also upload a video where you show me what you’re doing and what you believe is not working. Then I can tell you if I see anything that looks wrong or out of place.

Sorry for the delay, this might help since I am not allowed to post video at this time.

If you are in a car traveling at 50 mph with cruise control and it is suddenly running at 90 mph even though cruise is set to 50.

That is what happened. I was running a cut at 20 mm/s when it sped up quite fast. Now when I try to send any jobs over, they run at very high speed.

I can only get the machine to slow down by having lightburn run at very low speeds.
For example to cut at 20 mm/s I have to have lightburn set at 1 mm/s
Here is a partial of the test file I was running at the time of the problem:

; LightBurn 0.9.16
; Smoothieware device profile, current position
; Bounds: X2.88 Y3.57 to X79.18 Y54.47
G00 G17 G40 G20 G54
G91
; Smoothieware clustering enabled
G4 P1
M3
; Cut @ 20 in/sec, 20% power
M106
G0X0.1143Y0.141
; Layer C00 Pass 1 of 4
G1X-0.0009Y0.0013S0.2F1200

In the last line you see the command F1200, this is the feed rate it should be running.

Here is the version I have running that cuts at the speed that produces a good cut, but I have to tell the machine to cut much slower to get it to respond. Similar to telling a car to run cruise control at 15 mph to actually drive at 50 mph.

; LightBurn 0.9.16
; Smoothieware device profile, current position
; Bounds: X2.88 Y3.57 to X79.18 Y54.47
G00 G17 G40 G20 G54
G91
; Smoothieware clustering enabled
G4 P1
M3
; Cut @ 1 in/sec, 20% power
M106
G0X0.1143Y0.141
; Layer C00 Pass 1 of 4
G1X-0.0009Y0.0013S0.2F60

You can see by the last line the feed rate was reduced from 1200 to 60 in order to get a cut.

I hope this better explains the issue.

You can upload the video to YouTube and share the link here - you can’t upload video directly to the forum. I’ll review your written response later.

I solved the speed problem. During the run cycle the job switched from mm/s to inches/s.

It took me a while to find it as the layout was still in mm. Checking the laser settings though it had changed. The machine was running 25.4 times to fast.

I have contacted Lightburn and informed them to the problem and the laser hasn’t given me any problems since.

the real question here is how did the setting change during a run cycle and why didn’t the layout on the software reflect it?

I am not a software engineer so I don’t pretend to understand it, I just know this drove me nuts!

Thank you for your help.

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