CO2 laser

[james34602]

I don't know about CO2 laser. Some question I want to ask...
1. CO2 laser company said nerver reverse polarity, but what happen if I reverse it?
2. If I don't use it long or just start a monent, is cooling really necessary?

 

[Pi R Squared]

I don't know about CO2 laser. Some question I want to ask...
1. CO2 laser company said nerver reverse polarity, but what happen if I reverse it?
2. If I don't use it long or just start a monent, is cooling really necessary?

1.

2. Yes it is.

Alan

 

[Cyparagon]

Reverse polarity will at the very least cause uneven wear on the electrodes. One is designed to be a cathode, and the other is designed to be an anode. If you switch their roles, tube life will be reduced. The clearance on the cathode to ground may also be insufficient to handle the high voltage (the cathode is typically grounded at the PSU, if memory serves), potentially resulting in flashover. Basically, the tube would crack and the PSU would shit itself.

You can safely operate the tube without water for about a second, if you leave it off for several minutes between firings.

 

[james34602]

Oh, such a danger scence will happen if reverse polority. DAMN!

 

[trussmonkey25]

Don't do it! Do not run it dry ever! Red equal positive black negative.

 

[RedCowboy]

Reverse polarity will at the very least cause uneven wear on the electrodes. One is designed to be a cathode, and the other is designed to be an anode. If you switch their roles, tube life will be reduced. The clearance on the cathode to ground may also be insufficient to handle the high voltage (the cathode is typically grounded at the PSU, if memory serves), potentially resulting in flashover. Basically, the tube would crack and the PSU would shit itself.

You can safely operate the tube without water for about a second, if you leave it off for several minutes between firings.

If I filled a 60w tube with automotive antifreeze or possibly mineral oil but did not circulate it, as an estimate how long could I operate it from a room temp start of 70F knowing the cool down time would be very long.

 

[trussmonkey25]

Antifreeze Maybe but not mineral oil. The antifreeze isn't as good as water but does protect from freezing. A 99c jug of distilled water is best

 

[Cyparagon]

My guess would be 10 seconds or so. Distilled water is better than glycols.

Just be aware if you suddenly apply cooling to hot glass, bad things happen.

 

[Arayan]

I suggest 40% ethanol. It works better than the simply distilled water!

 

[Cyparagon]

Was that a vodka joke, or are you serious?

 

[Arayan]

Was that a vodka joke, or are you serious?

Both I use it often as a coolant instead of the best but more toxic methanol, in the distillers.

https://en.wikipedia.org/wiki/Antifreeze

 

[Cyparagon]

Ethanol holds less heat than water. There's no reason a CO2 laser would need to be resistant to freezing, unless you're running it outside or in a garage in winter. And that would be a bad idea anyway.

 

[Arayan]

Ethanol holds less heat than water. There's no reason a CO2 laser would need to be resistant to freezing, unless you're running it outside or in a garage in winter. And that would be a bad idea anyway.

Wodka is better