Re: Thermal runaway when using cooling fan
Hi,
11V is fine, that will not be an issue. Try also run P.I.D. calibration, it could help. Also try to reduce max fan speed in Slic3r. It is not really a solution, but at least you can see, how much you have to reduce fan and therefor how big problem you have. What also helps is the hotend silicon sock, but I do not like it.
Milos.
RE: Thermal runaway when using cooling fan
Since I've been using Kapton tape, I haven't had any problems.
RE: Thermal runaway when using cooling fan
I'm having a similar issue, even when I get the cooling fan to turn off the first 5 layers. This happened in the middle of a run of 20 identical prints, no upgrade to firmware, no changes to anything. I was printing 20 of the same file, one after another. Then I suddenly get the thermal runaway. Watching it, the temperature drops slowly until it is too low.
RE: Thermal runaway when using cooling fan
I put a E3D silicon sock on the heatblock, temp no longer budges with fan at full speed after having runaway issues.
RE: Thermal runaway when using cooling fan
I have the same problem. I have up graded the firmware and dividers to the latest version. I also have upgrade to the latest version Slic3r. I started having trouble when I printer a project form the Prusa site (Toy Train 4 car set). Everytime I printed a single part or many parts at one time after the first layer was completed and the fan came on. The fan was set for 100% and when I looked at the fan speed it list as 255. I quickly adjust to 100 and the temp came right back and the printing was completed. Each time I caught it right after the fan came on. I have print any thing new since. When I start looking for the problem in the beginning I found that one of the wires connected to the hotbed had over 50% of the wire strands broken. I cut both wires off and resolded them.
RE: Thermal runaway when using cooling fan
The cooling fan cools the nozzle too much. I had this same problem when printing MakerGeeks PLA (235°) until I found that if I set the cooling fan to a maximum of 50%, the problem goes away and I still get good prints.
With lower temperatures (below 220°), I do not have to set the fan to a lower speed (or when the ambient temperature in my garage gets above 35°).