I have a heavily modified CTC I3 Prusa Clone running an E3D Tornado Bowden set up. It prints great but I wanted to set up one of my Raspberry Pi's with an Octoprint server to print over the network.
I have got Octoprint all set up on a RPI 4 connected by USB to the GT2560 board on the printer. It seems to connect great except for 1 thing... I can't get the hot end temp to stabilise and it never starts printing. Set to 230 for my PETG printing, it fluctuates from 225 to 235 constantly.
At first I thought I should re-tune the PID which I did and it made no difference so I went back to my original tuned PID settings.
As the temp has always been completely stable before hooking up the Pi, I'm thinking the new Pi and Octoprint is causing the issue?
With the Printer plugged in to the Pi and Octoprint, I get wild temp fluctuations on the hotend. This is also shown on the LCD of the printer. As soon as I unplug the Pi from the printer, the temperature is completely stabilised at 230. If I plug it back in, the temp fluctuations come back.
With this in mind, I don't think it can be the printer hardware or hot end kit. I also have a good quality USB cable
The printer is also running marlin 1.1.8 at present