I'm curious what you guys use to cool your laser tube.

I’m curious what you guys use to cool your laser tube. Just water? If so how many gallons is the bucket and what kind of pump? Or something else…I thought I saw coolant or antifreeze mentioned on a youtube video.

It’s recently been determined by Don and others that antifreeze is too conductive to be used near the high voltage of the laser. So just distilled water, with a few drops of aquarium algaecide if algae is an issue.

I’m just getting into this stuff, so I’m using the cheapo aquarium pump that came with it. Just a gallon of water for now, probably go bigger if I start using the thing constantly. I’ve got a thermometer in the tank, if it gets too warm I can throw a frozen water bottle in.

Some people run water coolers or chillers, if they’re running high production.

Ideal operating temperature is 15-20c higher than that and your laser power diminishes. Somewhere above 30c you start shortening the life of the tube.

You can see this post here for some recent disscusions on the topics https://plus.google.com/113684285877323403487/posts/jDRGVhd6zqy
At this time I believe we have come to consensus that it’s best to use distilled or DI water with a small amount of bleach or aquarium algaecide to prevent algae growth. Just make sure the algaecide is not copper based. Adding a small amount of alcohol (ethanol or isoproply) is probably fine as well. Car antifreeze is a definite no and RV antifreeze is still not recommend as well. I think most people use a 5gal bucket as a cooling water reservoir and add ice packs/frozen water bottles to the bucket as needed to keep the temp down during long jobs.

@TwelveFoot thanks that’s good to know. I have a 5 gal Home Depot bucket with the stock water pump that came with it. I thought the antifreeze was a bit much. But good look on the temp…i was curious about the operating temp. I knew above 30c was too high, but I’ll make sure to keep it below 20. I’m just setting it up and have only run a couple engraving tests so far. No cuts yet. It stays between 23-25 c. But I’ll cool it down.

Up to 25C is unlikely to do any damage to the tube especially for short runs. Less than 20C is just a conservative recommendation, especially for long runs.

@Nedman just read the whole post, awesome…gotcha 5 gal distilled water (ice as needed) + 1 oz bleach. Thank you sir

I only use water with a few drops of bleach for algae or slime control. The more volume the better. It takes more time to heat up the water when there is more volume. 5 gallons gives me 10 minutes of work from 60f to 65f. Will be doing 10g aquarium soon. Hope this helps.

And when I hit 65f. My 8ma power goes down to 6ma. Btw I have a 3 year old co2 tube

I´m using distilled water, biocide made for computer water cooling and a dash of water wetter, to bring down the surface tension of the water (stopping bubbles to form in the tube).
If water wetter is better or worse than dish soap i don´t know, but seen to conductivity it´s really low.