# Liquid Nitrogen



## KPeacock (Jan 29, 2013)

I've purcahsed it at a welding supply shop before. 

I'll bet praxair, or airgas could direct you to a local supplier


----------



## Benthic (May 1, 2011)

Agreed. Both of my local gas suppliers (Airgas & Wesco) have liquid oxygen. I haven't asked about liquid nitrogen, but if I were looking for it they would be the first people I'd call. 

Brian


----------



## cg3 (Jan 16, 2011)

Our welding supply can get it, but you have to supply your own dewar (thermos).


----------



## KPeacock (Jan 29, 2013)

cg3 said:


> Our welding supply can get it, but you have to supply your own dewar (thermos).



Yup, I forgot about that part. I did have to bring my own dewar. I got mine off of ebay for something like 60 or 70 bucks.


----------



## scoots40 (Mar 10, 2008)

Sorry for my ignorance, but what is this used for? I would guess small hive beetles, wax moths, possibly mites, but I have never heard of this treatment. Seems an interesting option.


----------



## Rader Sidetrack (Nov 30, 2011)

> Sorry for my ignorance, but what is this used for? 

_Search _is your friend! :lookout: The thread below is illustrated, too 

http://www.beesource.com/forums/showthread.php?270929-Hygenic-test-results-on-breeders


----------



## cg3 (Jan 16, 2011)

Well, I used it for making ice cream.


----------



## Nature Coast beek (Jun 10, 2012)

@scoots40

Used for brood kill to test hive for hygienic trait.


----------



## KPeacock (Jan 29, 2013)

I used it for quenching steel coming out of the forge. Some steels (52100 and 5160 particularly) respond well to very deep quenches and then tempering cycles. it wouldn;t have anything to do with beekeeping unless you wanted a very robust hive tool  The stuff is incredibly cold , below -320deg F, so it will freeze most stuff pretty dang quick.


----------



## Alyeska (Mar 15, 2012)

Its also extreamly dangerious. Spill a litle of it on you, and you might be loosing a limb, or worse. Yes, its very usefull stuff, but, its also extreamly dangerious. No, I can't repeat that enough, its that dangerious. Err, its also used in cryo freezing things, including humans. Some studys have been done on freezing bees, and, actualy, be interesting to see if the fed has any good queens frozen and stored somewhere.


----------



## gmcharlie (May 9, 2009)

KPeacock said:


> I used it for quenching steel coming out of the forge. Some steels (52100 and 5160 particularly) respond well to very deep quenches and then tempering cycles. it wouldn;t have anything to do with beekeeping unless you wanted a very robust hive tool  The stuff is incredibly cold , below -320deg F, so it will freeze most stuff pretty dang quick.



Never used it on hot steel?? (oil or sodioum only) how does it react?


----------



## Aerindel (Apr 14, 2012)

Its actually very hard to hurt yourself with it. Back when I was in school we had a teacher who would pour it over volunteers hands as a demonstration. It has such a low boiling point that it flashes into nitrogen gas on contact with something as hot as skin and insulates itself from your skin. You have to immerse your hand into a body of it for some time to actually freeze yourself.

Whats more dangerous is the substances that have been chilled with it. A metal tool for instances chilled to liquid nitrogen temps will instantly cause frostbite on contact since there is no liquid to boil into a protective gas.


----------



## rainesridgefarm (Sep 4, 2001)

We use it a lot to freeze brood to test them for hygenic traits. I started using it with gloves and safty glasses but now I just pour it in the can and put the frame back in the hive


----------



## Blackwater Bees (May 7, 2012)

Aerindel said:


> Its actually very hard to hurt yourself with it. Back when I was in school we had a teacher who would pour it over volunteers hands as a demonstration. It has such a low boiling point that it flashes into nitrogen gas on contact with something as hot as skin and insulates itself from your skin. You have to immerse your hand into a body of it for some time to actually freeze yourself.


Tell that to the people who I burn skin lesions off of with it. I feels like a hot coal on your skin, and the spot dies and falls out in a couple of weeks. Please don't play with it at home.


----------



## Sharpbees (Jun 26, 2012)

If your going to do a hygienic test where you kill the brood take a can of compressed air, the type used for cleaning keyboards, turn it upside down and spray the desired area for a few seconds. Don't get your hand in the spray or you'll get a freeze burn.


----------



## O'Quinn (Oct 20, 2009)

Sharpbees,

Have you tried this? I used dry ice and did not get a complete brood kill. Liquid nitrogen is the only thing that I have used that is cold enough to consistently get the job done. The brood itself has to chill and die to get a true test. 

O'Quinn


----------



## Michael Bush (Aug 2, 2002)

I get mine at the local welding place. Shop around for a dewar. Some are VERY expensive, but you can find some bargains too.


----------



## Sharpbees (Jun 26, 2012)

It worked for me but I've only tried it once. I wasn't killing as large an large area though.


----------



## dnichols (May 28, 2012)

I think Aerindel was referring to the Leidenfrost effect. You can actually immerse your hand into liquid nitrogen BRIEFLY with no ill effects. Because of the low boiling point of LN there is a barrier of Nitrogen gas that protects the hand momentarily as the warmth of your hand boils the LN. I teach this concept to my physics students. Would I recommend the practice. NO! But it is a cool physics principal. Key words here guys! Briefly and momentarily. There will be a quiz on this tomorrow.


----------



## Aerindel (Apr 14, 2012)

> Tell that to the people who I burn skin lesions off of with it. I feels like a hot coal on your skin, and the spot dies and falls out in a couple of weeks. Please don't play with it at home.


How is it being applied?


----------



## Michael Bush (Aug 2, 2002)

> You can actually immerse your hand into liquid nitrogen BRIEFLY with no ill effects.

I cringe just reading this. PLEASE, no one attempt this!!!


----------



## KPeacock (Jan 29, 2013)

gmcharlie said:


> Never used it on hot steel?? (oil or sodioum only) how does it react?


Well, it reacts a lot like you'd expect when putting someting thats arounf 1500deg into something at negative 300 deg. a fair bit of isntant boiling going on. this must be done in a well ventilated area becasue it quickly puts out a lot of nitrogen gas. The end result was a very nice knife, but i don;t think it was worth the effort. i havent had a knife break yet, but i wanted to try it as i had read a fair bit on the subject.


----------



## Rader Sidetrack (Nov 30, 2011)

dnichols said:


> I teach this concept to my physics students. Would I recommend the practice. NO! But it is a cool physics *principal*. _Key words_ here guys! Briefly and momentarily. There will be a quiz on this tomorrow.


Will the appropriate use of the word *principle *also be on this quiz? :lookout:Your _principal _may take a dim view of being dipped in liquid nitrogen, regardless of the _principle _you are attempting to illustrate.  _Key words,_ indeed!


----------



## gmcharlie (May 9, 2009)

KPeacock said:


> Well, it reacts a lot like you'd expect when putting someting thats arounf 1500deg into something at negative 300 deg. a fair bit of isntant boiling going on. this must be done in a well ventilated area becasue it quickly puts out a lot of nitrogen gas. The end result was a very nice knife, but i don;t think it was worth the effort. i havent had a knife break yet, but i wanted to try it as i had read a fair bit on the subject.


 Thanks.. Familiar with cryo treatment on finished steel never heard of useing it as a quench. Brain tells me it would still be hard as glass and teh temper needs to be softened, but I suppose it could also effect grain size. wondered if the gas would have been so violent it would be dangerous...


----------



## dnichols (May 28, 2012)

Rader Sidetrack said:


> Will the appropriate use of the word *principle *also be on this quiz? :lookout:Your _principal _may take a dim view of being dipped in liquid nitrogen, regardless of the _principle _you are attempting to illustrate.  _Key words,_ indeed!


HaHa! I knew someone would catch that! Oh boy...You should meet our principal. 

I didn't bother changing it because I figured the reply would fire people up anyways. Grammer and spelling aside.


----------



## dnichols (May 28, 2012)

****DISCLAIMER**** 

DO NOT DIP YOUR HAND IN LIQUID NITROGEN

Everybody hear that?


----------



## minz (Jan 15, 2011)

Caution for stiches! (not what you think). We used to pour it into our IR camera when doing inspections. One of our tech’s did not have a dewar and put it in a thermos bottle. He was fighting to get the top off of it and when it finally came off it hit right in the forehead and knocked him back in his boots. Tell you what, thermos bottle stopper to the forehead really bleeds.


----------



## cerezha (Oct 11, 2011)

Yes, LN2 (liquid nitrogen) is dangerous and I know it for sure since I am working with this substance for 30+ years. No jokes around LN2, it is literally, deadly serious. It is dangerous when it gets:
- on your clothes - more dangerous than direct skin contact;
- in your eyes
- evaporated in small, non-ventilated area
- inside your boots...
- it may splash violently

LN2 burns heal very slow and painful, there are huge scars after that.

If got it - treat it as a severe burn from boiling water. 

Beekeepers need to know that the best remedy against burns is a propolis tincture (1-5% propolis in alcohol) - apply every few hours,works great on my 3rd degree burn from 50 sparkles...


----------



## KPeacock (Jan 29, 2013)

Yes, the idea was to have a VERY fine grain after the quench and then temper to reduce the brittleness. I am a pretty small time knife maker and sadly, i didn;t ahev teh time to appropriately test my results. it would ahev been nice to destry the knife to see the grain structure, and also test the rockwell hardness. i did neitehr and had to settle for simply flexing it in a vice and giving it a thumbs up, or thumbs down.

The birth of my son has shelved my knife making for the forseeable future. I just don't have the solid blocks of time required to make the damascus steel anymore. I dealt mostly in damascus because it plain old looks cool when done. Even monosteel blades take me a relatively long time to make as i choose to avoid the use of power tools. I know it's all in my head, but i like the feel of a blade that hasn't been abused my power tols, but rather has been coaxed into existence with simple tools used by a simple human. Clealrly, I have no hope of making acareer with this mentallity. Once the boy gets biger and can "help" me, I'll pick it back up again.


----------



## cerezha (Oct 11, 2011)

KPeacock said:


> ...Yes, the idea was to have a VERY fine grain after the quench and then temper to reduce the brittleness. ...


 I am sorry to interfere, but it seems to me that the idea of using LN2 (liquid nitrogen) is not really great. Since LN2 evaporates very quickly, it creates a gas "cushion", which works as an insulation. So, LN2 cold temperature actually did not reach the metal in timely manner. It is my understanding that in quenching what is important is a speed of cooling, not absolute temperature. In case of LN2 because of the gas "cushion" the speed is slow. In research Lab, we used to use a liquidized freon to eliminate the gas "cushion", but I am not sure that freon could survive a direct contact of very hot metal... another Lab option - is super-cooled ethane, but it is extremely flammable... oil has a very good heat-conducting property. Water - the same as LN2 - vapor's "cushion".


----------



## Aerindel (Apr 14, 2012)

I also a knife maker (well, swords mostly but you have to start somewhere) I've used acetone cooled to sub zero temps with dry ice, it also works very well and is easier to get than nitrogen.


----------



## Michael Bush (Aug 2, 2002)

Making knives I've always been quite satisfied with quenching in oil... after getting it hot enough it does not attract a magnet...


----------

