Hey,

I recently picked up a 40W Chinese CO2 laser cutter, which I'm currently using in my attached garage (I have good ventilation out there). We're coming up on the winter months, and though it doesn't get extremely cold here (Virginia, USA), it does get below freezing outside, and my garage may dip below freezing on occasion. I'm worried about my water freezing and cracking the laser tube. What do you guys do about keeping your laser tubes from freezing in the winter? Surely not everyone has a climate controlled workshop, right?

Is it safe to add a bit of antifreeze to the water? I was thinking about using a 50/50 mix of Propylene Glycol antifreeze, like Sierra ( PEAK | SIERRA | Antifreeze / Coolants | Auto Products ). I guess the other options are blowing out all the water from the tube... or moving the whole thing inside (in which case, it'll basically never get used this winter).

Is there anything else I need to consider regarding the laser in the winter (is it okay to run while cold, or do I need to warm it up first, etc)? I'm familiar with the precautions of using electronics in the cold... but CO2 laser tubes are new to me.

Thanks,
Pat