Liquid nitorgen, vids/pics (updated)

Quote
NoCoast
It was 20 in the shop to start.

OK long undies and jeans.

(No heat in the shop I had in fawkin Bawstin...fawk.)

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

And we had the full body Carhart just sitting there. Still had regular old skateboard style shoes for most of us.
Yeah, probably was more like 6". You hit where is frozen, it's not like an exact science. Start at top, spray, spray, working left to right and back for a few inches wide, crack, hammer, move downward as it goes. It's a very fluid process. One of those things that I think a few puff puffs and some good reggae could really get you into the mood and moving along nicely.

---

Grant Hughes

So, what did you do?

---

Don Kennedy

---

Grant Hughes

It's still sitting in my upper garage. After looking over the tank i'm pretty sure you could tip it on its side. Not sure how the pressure valve would handle it, if it would just build pressure or spill LN.


Regardless I think me and my dad will be able to muscle it down the hill. I dont want a dolly even though he has a furniture dolly, it could easily get away from you its very heavy. It has a solid base, so I'm pretty sure if one person holds it from tipping, the other can just push it.


We're doing it saturday, i'll post some pictures.

Steve did the Death Ray Arrive?

Quote
sidewaez
Steve did the Death Ray Arrive?

It did thanks! I appreciate it. FYI to anyone that wants it next I have it. I'd just suggest not to request it and sit on it for months until you're actually ready for it. I'd rather ship it to someone whose going to use it within a few weeks of me shipping it.







Edited 1 time(s). Last edit at 11/01/2013 06:23AM by czwalga.

My goal is to get my shell on a custom rotisserie, but I'm not ready for it yet. Especially after ripping everything out of the rally car today: engine, front/rear subframes, diff, seats, suspension, etc.

Alright so, everyone can actually see the process I tried to take a video of it. It was just me and my dad so no one to really take videos. The clip is him trying to hold the death ray and chip at the same time. Its really a 2 person job.


FYI, we were able to get the tank down the hill without a problem. Cut a 4x8 sheet of plywood in two and was able to just slide it down the hill. The tanks base is wide enough that it didn't take much force to keep it upright even when on the steepest part of the hill.


Some thoughts on doing this. Took a while to get the hang of it, we actually cracked the shell in the weaker areas a few times when we started. If the stuff is frozen and ready to come off you dont have to hit it hard. Once we got the hang of it we didnt crack the metal anywhere. Not a big deal just have to weld a little more in a few places.

A fan is absolutely necessary, would have been nice to have a 3rd person holding a fan the entire time time and positioning correctly. Its very difficult to see especially when you're working in small corners where the gas will circle. The flat areas an fan blowing was good enough.

Its much much easier to start and keep going. If you start and stop it takes a long time for the hose to cool down to where liquid is coming out and the shell to cool everything enough so that you can move quickly.

A 180l tank is barely enough. We wasted some and didnt get everythign I wanted to, but we got most of it. The key is if you get most of it you can go back with a scraper or wire wheel later as it doesnt adhere to the metal nearly as well after being frozen. You can kinda hear the stuff cracking off the shell.

A metal scraper works really well on the flat areas. Freeze it, give it a few taps with the chipper, then use a scraper.


video: ?t=18s


Wheel well before and after. The wheel was was hard to do due to not being able to see. The fan created a vortex in there.







Edited 1 time(s). Last edit at 11/04/2013 08:16AM by czwalga.

A fun thing is the little remaining "Cling-ons" have lost their grip and will brush aside wif a little skim of the cup brush..



Isn't that just fawkin amazing?

Next time I'm getting a buncha shit from these guys who say "If its not your idea...because yyou're selling it" tell them to look at that and eat shit and die.

And those retarded dinosaurs who say "no other way to do it, just propane and a chisel.." or ACID DIP, tell them to shut up and get with the 90ies.

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Well, in defense of those who argue for heat instead of cold, there's the issue of stress-fractures in the sheet metal from being super-chilled unevenly. This is much less likely to happen with heat, because the metal is always warm enough to be ductile.

Not that I know that stress-fractures happen when using the "death ray"; just that this is the argument that I've heard against this approach. And if this point has been discussed and already ruled out, apologies for not searching enough.

What issue of stress fractures from cold? We did break through here and there, but really, what stress fractures? Burning glue makes me feel like I'm giving myself cancer.

---

Grant Hughes

Quote
NoCoast
What issue of stress fractures from cold? We did break through here and there, but really, what stress fractures? Burning glue makes me feel like I'm giving myself cancer.

Actually, I'm not sure that's a terrible guess. I sorta wonder if the freezing might've led to some of the fractures seen when the rear diff tried to remove itself from the Compact. To me it was just really strange to see factory spot welds tear in that manner...and by tear I mean clean snapping apart.

That said, agree fully with grant that heating and scraping is miserable for many reasons. I really wish there was someone locally that did acid dipping...no idea what that method costs though.

Dave

Quote
DaveK

Quote
NoCoast
What issue of stress fractures from cold? We did break through here and there, but really, what stress fractures? Burning glue makes me feel like I'm giving myself cancer.

Actually, I'm not sure that's a terrible guess. I sorta wonder if the freezing might've led to some of the fractures seen when the rear diff tried to remove itself from the Compact. To me it was just really strange to see factory spot welds tear in that manner...and by tear I mean clean snapping apart.

That said, agree fully with grant that heating and scraping is miserable for many reasons. I really wish there was someone locally that did acid dipping...no idea what that method costs though.

Dave

From what i've seen about 1400-1800; for a bare shell.

Quote
czwalga

Quote
DaveK
That said, agree fully with grant that heating and scraping is miserable for many reasons. I really wish there was someone locally that did acid dipping...no idea what that method costs though.

From what i've seen about 1400-1800; for a bare shell.

If there was someone locally, I think that'd be my preference at those prices if doing a high-spec build. I think our LN was about $700 to do the car. Plus having 3 people work on it over the course of a day or two. Even when we were done, there was still a bunch of prep work to some seams and remove paint for welding.

Dave