Newbie with questions...

[FoxTrottZero]

Heyall... I'm a newbie phasechanger with limited (college budget) funds.
Getting all jazzed up about autocascades. I understand how they work (theoretically) and would like to build one... but fear that I'll have to concede to a single stage, beginner system for my first build...
Questions: obviously, colder is better... down to a point at least. What kind of difference in closkspeeds have you guys seen between -30 and -150 celcius? is it worth it to go the extra mile and really all-out freeze the system?
- I talked to an HVAC/R engineer who was disapointingly pesimistic about amateur direct die refrigeration... He wouldn't help me with anything, saying that I would kill myself and waste his time. I'm an intuitive person; started my own acoustic guitar company at 18. I can tell from my months of research, that simple refrigeration is not really all that complicated... obvioiusly, refrigeration is as complicated as you want it to be, but for a simple, raw cooling system, it seems like this is more fun than sweat... Is there any information I can get from here on how to calculate variables and design a system that "should" work from the start? I'd really like to try crunching numbers to see how well the loop works without any tweaking...
-From what I gather, there is no recipe for a phase change pc cooling system... it seems like two people with the same set of parts could end up with completely different (I.e., huge differences in captube length, block design, insulation... etc.) systems yeilding the same results... correct?
Much appreciate the help everyone.

[masterofpuppets]

Autocascades aren't for newbies. Build a simple single-stage system first. Autocascades can kill if not done right. I've helped my uncle build an autocascade (he's an experienced engineer) and I have also studied autocascades for a long time, built single-stage systems and I am still not confident enough to build a simple 2 stager. So I recommend taking apart an old freezer or buying a window AC unit and making a waterchiller, then build a simple single-stager before you even think of making cascades. Besides, a cascade is expensive, and your on limited budgets.

[fatty]

I would buy a broken prometeia and modify it to begin with try different gasses etc then go from there

[bxa121]

walk before you run...
its better and youll learn more from building a single stage system than visiting casualty with blast injuries....
once youve done the singla stage you can always fit it into an autocascade later....

you gotta remember. theres a difference with knowing something and doing something!!!

[Dissolved]

Seems like every week we get another one of these threads...

Buy a mach1 from ebay for 300bucks. use it, learn how it works, then mod it.

if your limited on fees you cant afford to buy all the tools needed to correctly build a unit, let alone a autocascade.

[FoxTrottZero]

Well... I already have many of the required tools. I have brazing and charging covered.
Just found a really big, really old compressor that works fine from a wall unit that does 7800 btu/hr
I also have a big 10000 btu/hr wall unit with a scroll compressor in it, but I'm having trouble getting it to run...

Like I said before... I'm kinda into the math behind the design of a refrigeration circuit. What I was asking for was advice in how to best go about designing my first system.
I've goofed around with a mach II before... but I want to build my own loop into a nice case and experiment a little with the evaporator block mounting design...