Printing in colder ambient temps?

I do the majority of my printing in the evenings after work, I will begin them and let the printer run overnight. After switching to PETG I have had quite a few new issues that I believe are related to the colder ambient temps in my unheated garage (temps drop to the 40-50s). With PLA I saw no major issues, but with petg I'm getting numerous thermal runaway halts and prints are pulling divots out of my glass bed..

Does anyone have any mitigation tips? I have lowered bed temp from 80 to 75C and this has helped print removal considerably, and I'm thinking about increasing the thermal runaway threshold in my firmware. I believe the runaways are caused because the bed and nozzle take much longer to heat in the cold, but I don't want to create any safety issues with increasing the runaway time in the event my thermister or cartridge gets loose. I have noticed the printer likes to shake nuts/bolts loose over time.

Put your printer inside an enclosure. I too had print issues due to cold ambient temps. I made an enclosure for my printer and my prints have never looked better. See this post for what I did. http://3dprintboard.com/showthread.p...ll=1#post78385 You don't have to go to the extremes I did on my enclosure. Simply putting your printer inside a cardboard box will make a world of difference. I just wanted to be fancy with mine. I don't need any additional heating inside the enclosure the heated bed is more than sufficient to heat up the air inside the box.

I am definitely going to look into the enclosure when it warms up a little bit. In the meantime, I have discovered that colder ambient temps make my print cooling fan wayyyy more effective, and as soon as that thing kicks on it drops temps enough to engage the thermal runaway parameters. I relaxed them quite a bit, but it still provides more cooling than the heater can overcome, so I will begin toying with fan speeds. Disabling it entirely has removed all thermal runaway cases, I just need to find out the ideal fan speed to retain the capability.