Guys,
I am absolutely lost on this one...
I installed my new MKS Gen 1.4 board, same behavior.
The thermistor is new - no splices or connectors except the one at the board
The entire hot end cartridge is very new, new heater core and block
I've run PID Tuning for hours. I've tried hand tuning. There is something else going on as far as I can tell.
I've tried using bang-bang, I thought it was better, but it isn't after running it more. Actually eerily similar.
The thermistor I'm running on the hot end is the standard 300C offering from e3d and slice
I get about 12-15deg slow up and down variation on the hot end. It is fairly cyclic in nature.
When turning on the printer, the ambient temperature of both hot end and bed thermistors reads some fluctuations, about 4 degC. 16C to 20C, I'm in the corner of my basement. Temp is cool, but constant.
I've upgraded from 12 to 24 V. I have a meanwell 24V PSU.
To try and eliminate the PSU, I installed my bench top power supply in place of the current one.
I tried ant both 12V and 24V. I get weird fluctuations at no load, ambient temp.
It will go wonky for about 60-120 seconds with 4 deg fluctuations, to running within about a deg for another 60-120 seconds. This is on both the bed and hot end.
I have searched and searched, and cannot for the life of me find anyone else that has had a similar problem.
The common answer to temp fluctuations seems to be PID tune, which has not helped.
Any ideas?
I'm at my wits end.
Dave