So after looking online for better water cooling solutions than a 20L container for the K40 laser, it seems that the norm is to use an industrial laser chiller.
These laser chillers start at US$800 ish.
If worst came to worst, I would buy one.. but I figured.. why not make one ?
I found an old bar fridge where the thermostat had died, but the compressor worked fine.
Here are a few pictures of the build process.
I have used a 12V external pump, with a buck converter to reduce the pressure down by reducing the voltage to 6V. Using a 12V Cage power supply used to power LEDs etc...
Decided to utilise a 20L stainless steel camping pot as the stainless steel wouldn't rust and would retain the cooler temperature for longer once the compressor came on
Utilized a digital thermostat picked up from ebay and set the temperature to 15C. The measurement is taken from inside the water.
Its crude.. but it works!
Not bad for parts mainly lying around!