That must have been on a tube manufacturers site where you read to run it at full power most of the time. To my way of thinking, that just burns up the gas faster and makes it run hotter. And I doubt any engraving you do would look very good if done at full power.
Do you know what chiller/cooler you are getting? You may want to add a little propylene glycol antifreeze to the water. I think this helps with heat transfer and helps prevent bacteria growth inside the tube. I noticed on mine before I used antifreeze, and I probably got lazy in changing the water, that the inside of one end of the tube started to get cloudy. On closer examination you could see it looked almost like a thin layer of white algae. That's the only way I know to describe it but I know it was something different. It was only on the cathode end of the tube. I started using the antifreeze and that stopped it. Just sayin'.
I know, I'm a regular chatter box today with posts here. I'm dividing up my time between the house and garage, and hiding from the wife because she has a bunch of "honey-do" projects for me.
Can't do anything outside without a beekeepers hat (which I don't have) because the gnat swarms are absolutely terrible where I live.
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