Question on firing a CO2 laser in a room that is now very cold.

[Ken Shea]

Would like to run some tests but the room the Laser is in is unheated and at freezing temps presently.
Can there be potential tube cracking issues with firing it at low temperatures?

It can wait till warmer weather just kind of wanting to get back on it.

Thanks
Ken

[Clark Pace]

If it's freezing make sure the water in the tube has not frozen. That could crack the tube when it gets warmer and the water expands. That is if there is water in the tube. You may have drained it for the winter.

[Dave Sheldrake]

Yes, very much so Ken, DON'T attempt to fire a laser tube at sub zero temperatures, you will likely crack the full reflector mirror or output coupler.

cheers

Dave

[Ken Shea]

It's not sub zero but tube are too expensive to unnecessarily risk.
It has water in it but is protected with antifreeze so that is fine.

I'll wait till warmer weather or take time one day to heat up the room long enough to warm up the tube as well.

Better safe then sorry as they say.

Thanks for the replies guys.

Ken

[Walt Langhans]

My laser is in the garage that is open and by no means environmentally controlled, here's what I have learned over the last 2 years when it get's cold (granted I live in Atlanta GA, so cold is retaliative but it does go below freezing here).

#1 Anti freeze in your water cooling supply.
#2 Check your belts. If it's cold enough they can contract and throw things off. If you are making parts they could end up not fitting together properly. I've had the cold weather throw off my horizontal axis as much a 1/16".
#3 Watch you amp meter, Laser love the cold. If I cut something at 100% power (via the software, I have my power supply dialed down to 95% to protect the tube) if it's cold enough the amp meter can jump up several point, which could be past your tubes recommended settings which will kill it almost as fast as cracking it with frozen water.

And then a +1 for what the other guys said about unnecessary risk and sub zero temps

Hope that helps :D