If I start a STL to print, the heated bed will rise to the correct temperature; however, if I try to heat the bed from Control or Calibration, it will not heat at all despite detecting the temperature just fine.
This started happening yesterday after a print was done. I noticed today there’s a firmware update (v1.14.3) and the issue still occurs after updating.
EDIT: Another weird thing that happens is after the first layer is done with the bed at 70c, it will change to 50c (which is normal) but the temp will actually drop down to ~37c and stay that way for a time then eventually go back up to 50c. Not sure why.
EDIT2: I’ve noticed even during the first layer, the temp doesn’t stay at 70c and slowly drops over time. It will get to 70c to start the print but then very very slowly drop temp. (i.e.; it’s at 60c at 30mins in)
What is your setup like? Which model? Do you have an enclosure (door open or closed)? What is ambient temperature?
Have you messed with the thermistor at all? Some early v2 users reported the thermistor wasn’t inserted into the hot end well. A bit of thermal paste and a shove got much better results. Although those users were usually reporting that the temperature reading was nominal, but they were burning PLA (ie, the head was hotter than it was reading).
This is an A350. The ambient temps shouldn’t matter and this for the bed temp not the hot end. The problem is the controller won’t heat the bed when I go to Calibration or heated bed section under Control. It will sit at ambient temperature of 27c (or whatever it might be) and never go up no matter the setting. If I go to print something, it will start heating the bed just fine. Calibration and Control are showing the correct temps as well, they just won’t heat the bed.
For example, if I go to Control → Heated Bed and set the temperature to 70c, it will sit at 27c/70c and adjust to ambient temp but never go up to 70c. Then, if I select a file to print where it has a initial layer temp setting of 70c, it will start raising the temp of the bed. It will get to 70c just fine and start printing, then go down to 50c after the first layer. If I stop the print after it’s heated the bed to 70c, then immediately go to Control or Calibration, the temp will show (for example) 67c/70c but continue to drop.
It’s detecting the temperature perfectly, it’s heating the bed perfectly while doing a print… it’s just not heating the bed while in Calibration or Control.
As far as the printing temperature, Luban supports an initial layer bed temp, and a bed temp. After the first layer is done, the temp will drop to the bed temp setting for the remaining layers. It sounds like you have those values set to 70ºC and 50ºC respectively. If so, you’ll see the target temp change to 50ºC after the first layer finishes.
I don’t have a V2, so I can’t help you with the control panel. It can’t be cabled wrong, or it wouldn’t work during printing. Does it let you preheat the bed during calibration?
ambient temps shouldn’t matter and this
Usually, but we’ve had a few people that were printing in a cold drafty uninsulated location during winter, with no enclosure.
As far as the printing temperature, Luban supports an initial layer bed temp, and a bed temp. After the first layer is done, the temp will drop to the bed temp setting for the remaining layers. It sounds like you have those values set to 70ºC and 50ºC respectively. If so, you’ll see the target temp change to 50ºC after the first layer finishes.
I only mentioned the initial layer bed temp and bed temps to emphasize that the bed heats just fine during printing but won’t heat outside of printing.
Does it let you preheat the bed during calibration?
No, I can’t even heat the bed in the Control. If I set a target temp, it never climbs.
The bed only heats up during an actual print.
After paying attention and doing longer prints, I’ve found out it when I start a print, it will get to 70c but very slowly over time not maintain 70c during the first layer. If the first layer takes too long (~30+mins) to print, the temp will have dropped enough to make the PLA not stick to the bed anymore.
As far as I know, I haven’t changed any settings. Here’s the gcode I tried to print and it got to the middle object before it wasn’t able to stick anymore: TrayLid.gcode (7.4 MB)
I don’t understand why starting a print can get the bed temp to 70c but it doesn’t maintain the heat, and the Control target temp and Calibration target temp don’t heat the bed at all.
This might indicate a bad connection, especially based on your other observations. While the bed is moving, it sounds like it is making and breaking connection, so I’d guess that the cable is bad. Contact Support, and they should be able to help you. It’s most likely a broken wire where the cable and bed meet.
Support is saying it might be the controller which would cost another $110 to replace since I bought the machine in Jan 2021. If I move the cord around and keep it held up in certain places (like I’m holding an old antennae in the right spot), it will start heating. There doesn’t seem to be anything physically/visually wrong with the cord or where it attaches to the bed but its quite annoying to be paying for a replacement part after 1.5 years and its in perfect shape.
I am hesitant to believe the support though because they also asked why I needed heated calibration when I can just use 25 point calibration. Why would you NOT use heated calibration on 5x5 as the bed warps with heat? Calibrating with heat means less margin for error. The support also asked, “please insert the plug to “Add-on3”, and power on the machine, then check if the heated bed is heating up over 70℃.”
If you plug the heated bed in any other plug than the heated bed socket, it will just give it power and not read temperature (it will show -15c) and give an abnormal status (it will show orange dot next to heated bed). Support has to know that I wouldn’t be able to see it heat to 70c right? However, I can feel it heat up.
I am wondering if I should open the controller myself and see if a wire is lose or shorting. Any suggestions?
This means that you have a bad connection somewhere in relation to that cable. It could be a connector, the connection of a connector to a PCB, the wiring attached to a connector, or the wiring itself. You should be able to use your multimeter to find the flakey connection.
This had been in question for years, and has been found to not be true in the majority of cases. The relative variance is typically less than 0.1mm, and for the vast majority of printers it is actually 0.05mm or less.
All of the Addon ports should be identical to the Heated Bed port, and all are functional alternatives.
If you are not seeing the temperature, then the connector on the cable is most likely bad. Moving the cable around as you were, might get it to connect in a certain position. If it does, then you have 3 options, 1) Purchase a new heated bed, 2) Purchase a new cable, cut off one end, and try to wire it yourself, 3) Ask Snapmaker to sell you a separate heated bed cable, which would be a special order.
If you go with option 2, ask Snapmaker which of the cables that they sell is the same length, or longer, than the heated bed cable.
All of the Addon ports should be identical to the Heated Bed port, and all are functional alternatives.
I don’t think that’s ever worked for me. Plugging the heated bed into any other port than “Heated Bed”
would only power it, but the touchscreen will say -15c and yellow light. If I have the bed plugged into the “Heated Bed” spot it will say the actual temp and a green light.
You’re able to plug your bed into Add-on3 and the touchscreen will show normal status and detect temp?
Ok, it looks like they changed the code in the controller so that the temperature measurement is no longer working when plugged into Addon 3. They are supposed to be swappable, as you normally connect the enclosure into Addon 3, and swapping them no longer works. This is probably a bug in the firmware. For me though, the temperature reading is 60°C when I plug it in to Addon 3.
The resistances are not relevant for the issue that you are observing. You should only be caring about continuity, to determine where the connections are broken. Find a connection that is broken, or is intermittently broken as you move the cable around. If it’s inside the Controller, it’s most likely a bad connector, cold solder joint, or broken trace on the PCB.
There isn’t anything that I can help you with beyond this. If you can’t figure it out, you either need to work with Support, or take it to a service center if there one near you. Only Snapmaker can help you at this point.
I am having the exact opposite problem. I can manually control the bed temp via luban or control menu via touch screen but when I start a print, the bed will not heat. I have tested this with the XYZ positioning in the same spot and right after one another, so I fail to understand how it could be anything other than a software issue.
