I am in the process of setting up and upgrading my 40W CO2 laser cutter and looking at the cooling system. I plan to use a PC water cooling system. But in order to make sure I plan the parts out right, I have a few questions that hopefully others already know:
1. What is the volume of liquid the laser tube holds?
2. What are typical temperatures of the water leaving the tube?
3. Has anyone measured the temperature of the glass on the laser? Is it hotter at the output end of the tube?
4. Would ammonia be safe to run through the tube? The reason being that it is more efficient at absorbing and releasing heat than water.
Currently, this is my planned system:
240mm radiator with 2 standard 120mm fans (fans may get replaced with thermopiles)
Latex tubing to the laser to ensure the tubes don't collapse
Flow direction will be from laser output to the rear of the tube (assuming that the output of the laser is the hottest part)
Check valves on the input and output to maintain pressure (to prevent air bubbles)
Flow switch on output as part of the interlock system
Temperature sensor installed inside the radiator that will be connected to a little circuit to kill the laser power if the water is too hot. Part of the interlock system
Reservoir (right now, it is a waterproof ammo box)
Pump (12V PC style pump or submersible fountain pump?) One of the reasons I am asking the above questions...
These things are planned just for gathering some information and probably won't stay a part of the system:
Flow meter connected to the controller board (RAMPS1.4) (this might be only temporary to gather information about the system)
Thermistor (temperature sensor) mounted to the laser tube
Ideally I would like the system to be as self-contained as possible. I am also wanting to shoot for "not way too much" but of course, not too little either. Being relatively quiet and efficient is the goal. My thoughts are that moving the water too quickly will not allow the water to absorb the heat from the laser. And having too much volume of water would make chilling the water more difficult.
If it isn't obvious, I am an engineer. lol. I know that I am overthinking things and much simpler systems will work by sheer brute force or by throwing tons of money at it to buy a chiller (overkill for a 40W system, I think.) But for me, this is part of the fun and if I can put together a self-contained, quiet, and efficient DIY system that is relatively cheap, then I think that could benefit others. So, if anyone out there already knows the answers to the above questions, it would be appreciated and save me some work taking a bunch of measurements.
Thanks for your attention!