Random Stops

Machine: K40 modded 12x24
Board: C3D LaserBoard
Firmware: Smoothie

Problem/ Question: Random stop during engraving.

So recently I finished my build of the K40 modded 12x24, Everything is working great except it would stop at random spots. I have another K40 Mostly stock with a C3D mini on it and it works great, so I tried switching out the power supply (24V 4A for the C3D mini) and USB cable from it as it doesn’t have this issue. I believe the one powering the Laserboard is from Cohesion3D which is also a 24V 4A. I checked the ground of my power, everything checks out okay. Computer is a iMac, which runs the other K40 fine, but just to eliminate any issues I have removed all other USB connected to it beside the keyboard, mouse and to the Laserboard. I switch the power outlet around, but this is the same power outlet that I run the Stock K40, which is unplugged for the test. I also checked the Console in Lightburn to see if I am getting any issues from there, most of the time it just stops where my machine stops. Maybe thought about getting a new Power supply for the Laserboard, maybe with a little more Amp like 5A. I’m stumped. Here is a photo of the board and K40 Power supply, created a box out of wood and painted, grounded to the machine and the outlet. Any suggestion would be greatly appreciated.

I have the same issue. I have an led laser with the C3d board and never an issue. Same cables to the k40 and it just sometimes stops, no error code. Sometimes it will just go an re-home. I’m about ready to pull it and replace with a Ruida….

Yeah it’s crazy how one works so well without any issue and another is so inconsistent. I have spent countless hours troubleshooting this. After searching more, found a user(Alin) using a Copper Box to resolve this issue, So I designed and 3D printed box to enclose the Laserboard, which I plan to cover in sheet of copper I have in my workshop, if this works, I would gladly share the design. Hopefully this will resolve my problem as I really don’t want to spend more money to troubleshoot this issue, I rather spend the time designing and creating things.

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yeah, it’s a shielding issue, almost certainly. The environment inside a laser case is pretty hostile to electronics that require precise timing, and a lot of laser power supplies are particularly nasty and noisy and emit a ton of EMI/RFI that interfere with those timing circuits.

I have found a big ferrite clip on the USB, close to the board resolved all my issues

Yeah my copper box didn’t work, but but was fun making it, lol. But soon realized that it was caused my chiller kicking in that caused my Laserboard to stop working, which is weird that it would still work sometimes when it kicks in, but other times it completely stops, so random. My C3D mini is on the same outlet and still this doesn’t occur, so strange. Before I spend the time and money bringing in a new line from my breaker box, I may try this out. What size is that ferrite choke? 13mm? You wrapped the USB cord twice? I am currently using a extremely long extension cord to make it work and it hasn’t stopped, but this isn’t a solution I can live with.

Its actually running as I take this pic, not sure of the size, I can put a caliper on it once its done later. There is a , what I guess is modle number on the side. Hope it helps, I think this should be standard with the sensitive boards

Also the new line* crap is bullshit. The interference from the power supply causes the USB connection to drop. I’m not going into details here, but through almost a year of testing, led me to try this approach :grinning: I’ve been running 6+ hrs jobs now with no drops

Also just for reference I keep my high voltage wires as far away from my motor and board power as possible, but as you can see, they are not that far apart

Thanks Nick for your feedback. I ordered my ferrite Choke last night, it was a set from Amazon, coming in tomorrow, unfortunately I’ll be gone all weekend so this will have to wait til Monday. But I finally finish a project using my extension cord. Been working on my K40 12x24 mod for months, overcoming one problem after another, felt like a curse project, but definitely learned a lot from this. Hopefully this will allow me to just start designing and create. I’m an artist/designer by trade so a lot of these “issues” are foreign to me, so it can be very frustrating to troubleshoot. Yeah putting in a new line was my last option, I recommend laserboard a lot on reddit, as my C3D mini has been solid once It was all set up, would hate to see people I recommend get this and run into this issue.

Cool let us know if it works, I think this be included or incururaged from the start

Can not get my graphics to burn as shown on lightburn. Doesn’t home, keeps trying to burn out of bounds. Really about to burn that board. \

So the Ferrite Choke is a no go for me. I even used two 13mm, but still stops once my chiller kicks in. I don’t have a lot of time to play with it until Monday, but will see if I can play with and give it another shot. But pulling a new line seems more likely for me. I wonder if my power supply had a little power like 5A, been reading that a lot of power supply actually has issues actually achieving 4A it is stated. But I don’t want to spend more money as I know a new line will actually work. Oh well journey continues.

Norman, sounds like your endstop is having an issue. Make sure you have the correct endstop plugged into the board, also I heard some K40 has optical endstop which can be a bit fussy, may want to replace it with a new mechanical one. Bought mine on Amazon for a set of 6 for under $10. Works great on my modded K40 when it works :rofl:

Throw a fat capacitor - like a 3300µF 50V - across the “separate power” terminals on the laserboard. That should help keep it from browning out.

Hey Loather, I’m down to try this but need a little more detail on “separate power” terminals, if you can elaborate a little more so I don’t fry my board. Like adding the capacitor between the 24v 4a power supply and the laserboard? Thanks.

You could put it there, but I’m specifically talking about the terminals on the upper-left in this photo:

Oh, lol, just placed an order on it should be here on Tues. Didn’t even think about that location, been a long weekend.

I had a similar problem, K40 reseting and returning to the home position at random, also sometimes when switching on the air assist or extraction fan. I tried an external mains filter, ferrite rings on power and usb cables (using a good quality usb cable) without success. The fix seems to be, connecting the usb to the PC via a cheap USB hub, no idea why it works, but in the 6 weeks since I did it I haven’t had a single problem.

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So I tried the Capacitor, same problem. Decided I try a different outlet for the chiller, This solved my problem. I just need to put in a new outlet from the one that is working. Much easier than pulling a new line in from the circuit box. Moving on. Thanks.

I was having an issue with the laser power supply. I tried the cheap USB hub and it worked for me. MONTHS of work and this worked lol. Thanks.