yes, basically the idea is that if your seeing temp swings it could be caused by the thermistor not reading the temperature of the heat block correctly. if it appears to be assembled correctly then the next step would be use something to help increase thermal transfer between the heat block and the thermistor. that way when the heat block temp goes up by 1 degree the thermistor temp goes up by 1 degree, without any significant delay.
does that help?
Absolutely thank you! I ordered some electrically non conductive thermal paste from Amazon. Should be here by Thursday. In the meantime my new Meanwell power supply arrived. I’ll be giving it a run once I connect power cables to it.
Dale
Well I put in the new power supply and no joy. Same as before. Printer shuts down when heating both the bed and the extruder. I think I got a lemon.
So far I am not impressed with Snapmaker and I don’t think I can recommend it to anyone.
I understand, i have had issues from the start too… if its not the psu the. It must be the controller… unfortunately that requires support to replace
I am really scratching my head on this one! I just tried to heat up the extruder and while it was on the downside of the temperature oscillation I then gave it the command to heat the bed. Watching the extruder temp going back up I expected it to shut off but it DIDN’T! So I thought let’s send the gcode file to it and see what happens. Voila, it started printing and has been for 19 minutes!
I hate it when I can’t find consistency. But it is starting to look like the power supply was the problem after all.
Dale
Failed after 50 minutes of printing. Ripping out the rest of my hair.
I don’t know much about the original snap maker but does it keep any logs that might give insight into why it’s restarting.
Have you tried a print without the heated bed? Or turn it off after the first layer?
@brent113 not yet but I have tried the laser engraving module and it seems to work with it. Not well though. The engraving is barely legible .
Hey @Dale_Chamberlain , what happened when it failed?
From what medium did you print?
There is no debugging option build in, the only way is to watch the serial monitor alias terminal to see what happened when it fails, i guess.
My next suggestion would be to change the usb thumbdrive to a new one (there where several defective original thumb drive and other thumb drives out there in the forum).
Hope this helps!
Here is the latest update: as of today (11/2) I received a response from Snapmaker support. They asked me to use a multimeter to test the ohms for the thermistor. I got a reading of 117.4K ohms. I don’t think the thermistor is the problem but I maybe wrong.
I put thermal paste around the thermistor and tried to run the gcode again. As before the printer shuts down when the temperature on the extruder is around 63C and the heat bed temperature is rising. So I tried manually sending the heat up command for 205C through the console and the temperature seemed to have less swings, but there were swings.
I am using the Meanwell 24VDC 6.5A power supply at this point and the printer stayed running as long as the extruder temperature was preheated before sending the gcode. I had the heat bed temperature set to 60C to start and 40C during the run. It got halfway through printing my project before it came off the heat bed. I’m guessing the heat bed temperature was too low, or I need to clean the bed.
Seems like some progress, but I still wonder if a heftier power supply is needed.
BTW, it doesn’t matter if I print from the flash drive or the USB connection to the computer. Same result either way.
Dale
117K would put your room around 22C. Sounds reasonable to me, thermistor is fine.
A 6.5A power supply might not be enough. That does seem to be the conclusion.
My Meanwell LRS-150-24 14.5A power supply finally came from Amazon. Swapped out the 6.5A with it and fired it up. Sent the gcode file without heating the extruder first and bingo! It heated the bed and the extruder without shutting down. Print ran all the way to completion without fail! Success!
So my guess is the nominal amp draw is between 5.2 and 6.5 amps. During start when everything is heating up I suspect it goes to 8 amps. Why Snapmaker is shipping these units out without an adequate power supply is the question.
Tomorrow I will try a project that is a bit more complicated to print. But I am a happy camper now.
Thanks for everyone’s support. It helps to have a sounding board while debugging.
Dale
So glad it is working! And thanks for posting the model number as well, I’m genuinely surprised there aren’t others with similar issues. Maybe your bed is a bit lower resistance than standard, and the design was pretty tight, not a lot of extra wattage headroom.