So my mini will reach 60 if I only preheat the bed and nothing else. If I begin to preheat the Hotend, the temperaure begins to fall. I purchased this printer and the heatbed was bad. I prdered a Heatbed via Amazon and did the wire relocation using the printed part. It was working okay, it seemed to heat up slowly, so I did a PID adjustment using the info from Tyler. Well, now it's worse than before and it seems as if though its progressivly getting worse. At first it was just one or two degrees and this is normal for these printers from what I have read. But it's steadily declining. Now my heat bed is set to 60c and it is floating at 47-48. I have opened the printer a few times and inspected visually the connectors and board, no signs of any damages, cold joints, burnt pins, etc... Any more help or advice would be welcome. I have a second heated silicone mat, and the Ramps board to add a second heater to the build plate just because the printer has always been slow to heat up. Fearful to move forward if there could be something else going on. Notable to mention I have two of these MPSM V2 with the most current Firmware. 1 in black and one in white. All of my problems have been with the white printer. Also notable to mention. The black printer from the factory has had the heat bed wires relocated to a newly added cuout in the body. Again, I have replaced the white printers heat bed and re routed the wires so they have no resistance or strain.
Id also like to add, It will still heat to 60C when you only preheat the heat bed. If you pre heat hotend and bed at the same time the bed will not reach 60 but the hot end comes within one degree of it's target
I had the same problem with my mini. Well, really i had the same problem on two minis. They were my first printers and both bed heaters went bad over time. The same as yours, they slowly declined in temperature. They both got to the point that the bed would never heat up no matter what i did. I never tried any fixes because i didnt know they existed. I did some digging and lots of people have the same problem. Something to do with the heating element. Now I will mention that i did not have both printers at the same time. The first one went bad and the second one was a replacement using the warranty from the company monoprice, but it to went bad. When did you purchase yours and can you still use the warrenty? The best solution I can see is using the warranty. I hate to be so doom and gloom, but that printer was nothing but trouble for me. Sorry for your misfortune and I hope you can resolve the issue soon.
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