Nice improvement! That heavy Argon charge is paying off well Would be really interesting to scale this up with about 2 to 3 times the capacity and try to use it on a processor.
Yeah it's a big increase in Argon, but as you noted it seems to be working well, and the running pressures have remained very reasonable. The subcooler is definitely doing what it's supposed to.

Scaling it up for CPU usage would indeed be a great project. Unfortunately it wont be me to do it, since I am looking to scale it down (more of a repackaging effort, then a capacity reduction), and end up creating a production ready prototype. I think there is money to made in this arena, all it takes is finding the right industrial/laboratory/medical marketplace. And as you know, not too many people know how to produce reliable working autocascades, especially very small ones.

Could you use a larger system with a frequency modulator to adjust capacity?
I don't see why not. In fact I think it would not only allow for excellent capacity adjustment, but also extend compressor life, by taking advantage of a ramp-up start-up ability.

Would the autocascade eventually crash as you adjusted the compressor speed? Just thinking the lower stages might not enjoy the lowered massflow...
I wouldn't call it crash, but if run too slow, you would eventually run out of steam. And yes the first signs of this might be a disconnection between stages, as you get out of the optimum range of pressure vs. condensation point for a given refrigerant.

I can't imagine using a ton of valves to adjust the capacity. Maybe a single solenoid on the evap feed to pulse refrigerant to maintain a temp but those solenoids aren't cheap.
Good point, and it could be made to work, but I suspect that the solenoid's life would be greatly reduced due to all the cycling required. Perhaps a better method would be to use an electrically controlled expansion valve. I think Sporlan offers something like this. And if coupled with a pwm output temperature controller, I think this would probably work quite well. It would simply replace the final captube.

-141,9 This merite respect!!!
Thanks plasmatique Quoting Rodney Dangerfield "I get no respect". Well luckily this isn't true for me, although in my business it doesn't come easily either, so it's always appreciatted.