RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   3rd Gen Archives (https://www.rx7club.com/3rd-gen-archives-73/)
-   -   Cryogenically freezing (https://www.rx7club.com/3rd-gen-archives-73/cryogenically-freezing-259845/)

Audi Man 01-11-04 02:00 PM

Cryogenically freezing
 
Anybody try cryogenically freezing anything? I know that it would help on some of the more weak parts of the engine, but have not heard any body actually trying it.

alberto_mg 01-11-04 02:19 PM

Check pineapple http://www.pineappleracing.com/

Also search, as there have been a few posts about the value of cryo treated stuff.

the_glass_man 01-11-04 02:54 PM

Has anyone ever performed this to the whole frame of the car?
I've been thinking about this lately, along with welding, and special foam to strengthen the chassis.

inis 01-11-04 03:33 PM

? That sounds like more work than its worth. It isnt ecaxtly the weakest frame out there. The car is pretty damn solid. You might want to save your money for other things.

ronarndt 01-11-04 05:45 PM

cryo treating frame
 
glass man- Where are you going to find a big enough container to put the whole frame in? I work with liquid N2 on a regular basis at my lab and you can not just fill any old container with it, since it will evaporate as fast as you fill it, unless the container is insulated. You might be able to fabricate something out of hi-density polyurethane foam, but then you would need several thousand liters to fill and immerse the frame in it to cool it. Simply dribbling the LN2 on the steel does not do much, you need to hold it immersed in the liquid to allow the steel to reach roughly the same temp as the LN2. You will also need some kind of air supply so you do not asphixiate yourself when the LN2 displaces the breathable air in the area where you are working and some way of handling a heavy piece of steel so cold that you can not touch it without freezing fast to it. This sounds like a lot of work and expense- but with enough $$$ it could be done.
Ron A.

TAMAatWork 01-11-04 07:50 PM

I think I saw an ad for that last week.

"Frozen for her pleasure."


Bump,
Joseph :)

jimlab 01-11-04 08:00 PM

Eric Cheatham had his head cryogenically frozen. Apparently it worked pretty well... :)

inis 01-11-04 09:58 PM

lol

dgeesaman 01-11-04 11:37 PM

Re: Cryogenically freezing
 

Originally posted by Audi Man
Anybody try cryogenically freezing anything? I know that it would help on some of the more weak parts of the engine, but have not heard any body actually trying it.
As a mechanical engineer I've seen no worthwhile evidence that cryo treatments make a measurable difference. I've read about it, and maybe it works, but nobody has put together an explanation worthy of my dollar. If it mattered at all the OEMs would be doing it. (trivia: automotive designers account for a tremendous number of specialty steels - so they do put a lot fo thought into this stuff). Considering that 95% of this kind of stuff is always snake oil, I wouldn't consider it until you've broken part X at least 3 times.

skunks 01-11-04 11:47 PM

if you wanna stiffen up the frame, why not just seam weld the entire car and weld in a full cage (a 400 dollar mig welder can do all the above and more) and i gaurentee you that it will stiffen up the chassie much more then freezing would do.

dgeesaman 01-11-04 11:56 PM


Originally posted by the_glass_man
Has anyone ever performed this to the whole frame of the car?
I've been thinking about this lately, along with welding, and special foam to strengthen the chassis.

You can't stiffen steel. Nearly all forms of low and high strength steel alloys have almost the exact same stiffness (stiffness and strength are independent things). The only thing cryo might do for that is make it less likely to bend and more likely to break.

Like Skunks said, the way to make it stiffer is to put in a rollcage and improve the welded joints. Nearly all production uniframes are weakest at the joints.

Godzilla-T78 01-12-04 04:01 AM

I had all my housings and rotors cryo froze.. does it help? I would like to think so, either way I did it just incase it does ;)

Snook 01-12-04 07:29 AM


Originally posted by jimlab
Eric Cheatham had his head cryogenically frozen. Apparently it worked pretty well... :)
HAHAHA whats his newest forum name

93BlackFD 01-12-04 07:38 AM

it exposes cracks in the metal so that the builder can detect weaknesses in the parts before reassembly

the way rob golden explained it to me, it was more of a step that he takes during inspection of parts rather than modification of parts...

make sense?

jimlab 01-12-04 09:26 AM


Originally posted by 93BlackFD
it exposes cracks in the metal so that the builder can detect weaknesses in the parts before reassembly
I believe you're confusing magnaflux testing with cryogenic treatment.


the way rob golden explained it to me, it was more of a step that he takes during inspection of parts rather than modification of parts...
Magnafluxing reveals cracks in ferromagnetic parts (iron, nickel, cobalt and their various alloys) not visible to the human eye by attracting magnetic particles to irregularities in the surface or internal grain of the part.

Cryogenic treatment theoretically relieves internal stresses and increases wear resistance and strength by cycling the temperature of the part down to -300° F and slowly bringing it back to room temperature.

FDNewbie 01-12-04 10:20 AM

check out http://www.300below.com/
it's got some interesting "cold hard facts" haha

I know for a fact that many cryo treating agencies have state and federal repeat customers for all sorts of parts (brakes, rotors, engine internals, trannys, etc) on buses, ambulances, cruisers, etc that are subject to a high rate of wear and tear.

I got my brake rotors & pads cryo treated by gotham racing...and they as well as irotors.com and other places that cryo treat swear by it.

apparently when you bring the temp down, the metal contracts, and the temp is brought back up slowly, but maintaining the metal's contracture permanently, making it much more strong, and dissapates heat much better as well (that's the explanation I've received)

KDRotary and Rotor Motorsports offer cryo treating for trannys and engine internals as well...so I would imagine all these well-respected places don't offer worthless services to the masses if they're not effective...unless this is your average TV infomertial typa product that they make millions off of cuz there are millions of idiots (for only $19.95) lol...

DamonB 01-12-04 10:45 AM

Re: Re: Cryogenically freezing
 

Originally posted by dgeesaman
As a mechanical engineer I've seen no worthwhile evidence that cryo treatments make a measurable difference.
Cryo is no different than surface coatings; they each have very specific properties for very specific applications. Just because a part is cryo treated doesn't make it better unless it's application can put the improved properties to use. Cryo treatments alter the crystaline structure of the metal and greatly improve the bonds between the crystals within the material. Cryo reating is the real deal.

Things like brake rotors, driveline gears and engine internals are prime candidates for cryo treatment.

Some info
here and here .

dgeesaman 01-12-04 12:35 PM

Spent my lunch hour researching this. I'm not the only person from an engineering background to catch a fishy smell.

Executive summary:
- Cryo appears to offer some improvement in specific steels for certain applications. Cryo suppliers are stretching these claims to grab as broad a market as possible and don't feel obligated to prove it has an effect.

Facts:

1) Cryo is effective in producing martensitic steel. Martensite is the hardest, most brittle, and wear resistant steel type, but usually contains some austenite. Cryo completes the quench process by transforming the retained austenite into martensite. Compared to the martensite/retained austenite mixture, it will be more dimensionally stable. Martensitic steels that weren't post heat-treated well can be improved.

2) The cryo suppliers claim it will make improvements to other metals, plastics, etc but provide no engineering data or theory to support this assertion.

My conclusions:

- for certain applications requiring wear resistance and extremely tight dimensional stability, cryo treating existing parts may help. It all depends on how much martensite the steel began as. EVERY CASE IS DIFFERENT. Just because bob cryo'd brake rotor A and found it lasted longer doesn't mean rotor B will do better with cryo.

Generally, the cheaper the original part, the more of an effect it will have since producing high martensite content is expensive and time consuming. Keep in mind martensite is more brittle (it breaks instead of bends) and has the same stiffness, weight, and ultimate strength. That's not always an advantage (car frames are safer if they bend near failure instead of breaking). So one common application is cutting tool steels - cryo improves the life of the tool substantially, but another alternative is to buy a better tool to begin with. Those costs must be compared.

In RX-7 parts, it's hard to predict what effect it will have since we don't know the composition or heat treatment of the OEM parts. Rotor housings and brake rotors stand out as a possible option since the OEM steel was made with cost and production in mind. I would love to see someone test before/after on these parts to see the difference.

- cryo suppliers don't supply hard data to substantiate their claims, and one supplier even complained they don't have the cash to do so (I lol on that one - a hardness tester is basically a hand press). The ones that have numbers are fuzzy numbers without testing details (an old trick that scientists and engineers are insulted by). I firmly believe cryo suppliers are taking advantage of this lack of information and are careful to make their biggest claims where it's most difficult to prove them wrong. Very few sites even mentioned the word martensite - I had to find that elsewhere. All they know is how to follow the directions with their cryo machine and copy-paste together a website based on others.

Will I ever consider cryo treating rotor housings and brake rotors? Maybe. I would love to see hardness tests before and after - this has to be done for each application to see if it had a useful effect. For brake rotors I'll probably just buy better rotors to begin with. Until I start discarding rotor housings due to excessive wear, I've got better things to worry about (like seals and tuning).

Dave


All times are GMT -5. The time now is 05:56 AM.


© 2024 MH Sub I, LLC dba Internet Brands