Marek, the $18,000 number is for the small Karcher dry ice blaster but as with all shop tools price gets you in the door and the you realize how much time it takes to do the job, so the small blaster may be a total waste of time as you will spend 10 time more in labor and hassle. I am not saying this $18k machine works, just that it is the entry level price for this equipment. I say that there is another machine to feed the dry ice to the gun and I have no idea what is involved so this makes the $18k figure even less reliable. But $500k seems like a number I can make a machine myself for.
Dusty cars claims to be only dry ice blasting his cars undercarriage and some of the bottom of his cars take great pictures but is he telling the whole story - doubt it.
Another person I know claims the dry ice removes undercoat. These are claims are by guys who are also known to be bullshit artists so you never know.
All I have ever heard of is claims but I have yet to see a the process in action, only seen the claimed end result. Most of my work has actually been a combination of multiple processes starting with good old hand labor and wire wheels on a big angle grinder removing a bulk of the material, then using sanding pads on a DA, chemical stripper, sand blasting soda blast sometime (although you do not want to use soda on any surface with exterior paint as the base in the soda reacts with the acid etching primers and can absolutely cause bubbling- paint manufactures void all warranties if you car has been soda blasted). Mostly the sand blasting on my cars is done on the areas where you can not reach with a DA sander or wire wheel and I have not always blasted every car.
Chris makes some good points but I have yet to see cars have panels that ripple because they were blasted and then driven, even vintage race cars. It's kind of like the science of electroplating cast iron - I have been told by plenty of people that a cast iron parts must be baked right out of the plating tank or the metal will crack - I have yet to see even the slightest crack on any cast iron I have done when the part is not baked. So the science may be correct but then there is reality and if the area of concern is actually happening on our cars - maybe a spacecraft goes through different conditions and it will happen in that world. I am not saying Chris is wrong at all just that I have yet to see it even on cars that have been blasted to death.
Oh and on the cooling of dry ice, maybe I am miss speaking, sandblasting causes a lot of heat, the dry ice and dustless blasting do not add heat to the metal so they knock off particles a little differently.
Right now the answer is that there is no one answer. I am afraid to sandblast my big flat panels, I am also a bit worried about acid dipping a body of a 911, and I am afraid of what the dustless blaster could do because of the water/bare metal combo, although undercarriages should not be a problem with the dustless blaster only the areas that have final color applied are to be worried about.
JP, when you go see the dry ice blaster demo maybe you can take a camera and record the action of the machine. If you have some cut up Porsche body section or fender or bumper lying around your shop maybe you could bring a piece and have them use the machine on an actual Porsche piece rather than watching them strip an item they provide.
Dustless blasting company shows a Cadillac being stripped in one of their you tube videos, however if you look closely the video is a setup as the car was painted with a single thin layer of paint - door handles, rubber, trim all are covered in the red paint as if they staged the shoot to make the machine look like it works fast.
Much more info experience and knowledge needed on this topic but great discussion.