Welding in Space

In space, metals can weld together without heat or melting.
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Written by Joh Howes and Derek Muller

Yes, it's pronounced Gemini (ee not eye) because that's the way everyone pronounced this mission.

Thanks to Patreon supporters:
Bryan Baker, Donal Botkin, Tony Fadell, Saeed Alghamdi

Gemini IV transcripts:

Gemini IV recordings: (relevant clip is 1297 at about 2:00)

ESA cold welding recommendations:

Cold welding gold nanowire:

Music by Kevin MacLeod "Intrepid"

Views: 811035
Runtime: 6:53
Comments: 1468

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Author nonya damnbus#1 ( ago)
Dammit now I want a payday bar.

Author Harsh Gupta ( ago)
i don't understand who dislikes videos like this

Author blackcatooow ( ago)
Get a camera with optical image stabilization. Your camera makes me dizzy

Author alfalfa fonzo ( ago)
4:20 who else hears a cockroach making its way to you from under the floor?

Author Based God ( ago)
if the space story had nothing to do with cold welding why even mention it?

Author Golden Grenadier ( ago)
I bet soldering is easy in space.

Author Dan Crouch ( ago)
do you need any shielding gas in space with there being no air.

Author T.P.K. ( ago)
yeah they slather grease on everything to mitigate any chance of stickage. The bigger the glob the better the job.

Author Matthew Topp ( ago)
I wonder how well a custom truck bumper wold hold up if you cold welded

Author WOFGH ( ago)

Author Eagles_Eye ( ago)
.. i tought it was about welding in space... dissapointmentttssss

Author Tadesan ( ago)
Why are you (and most other channels) asking for financial support? If making these videos is such a burden then stop making them.

Author Nicolas Gleason-Boure ( ago)

Author Cameron Wofford ( ago)
1 payday + 1 payday = SUPER PAYDAY

Author 777Dubliner ( ago)
stainless steel loves to cold weld, I was assembling a part when I was new to the machine shop Im at and wasnt told about applying anti freeze, the bolt went in but I had to take them out because I forgot a part to put on and one locked right up, that was my first and this far only experience with it, lesson learned

Author Kristanto Nugroho ( ago)
SO, our processor that enabled us to watch this video are manufactured in cold, vacuum chamber?

Author Noah Williams ( ago)
Are cold welds weaker than heated welds?

Author Kainafar ( ago)
If something is sufficiently flat, it will "cold weld" in the earths atmosphere. High quality gauge blocks will do this.

Author abc def ( ago)
cold welding shouldnt take place, all the youtube videos i saw, they were pressure weldings or friction weldings or electrical potential weldings, including this video. they seem to insert the external energy into the system of metals, this is a cheating.

because when an electron tries to leave the metal, an image charge appears in the metal, and the metal sucks back the electron into the metal. in other words, a work must be done on the system to eject the electron. please check E&M 101.

Feymann was wrong, or he probably meant the nano meter sized metal where QM dominates. the nano size is not in the region of the classical realms of physics.

Author superslash946 ( ago)
Man, you truly are an inspiration. Your videos are by far the coolest educative vids out there! Just wanted to tell you I just finished a university paper on cold welding inspired/based on this video! Thanks for the help! xD

Author me larrieu ( ago)
Footage is stop motion smh

Author Brian Kelly ( ago)
Chocolate covered Payday bar. Finally science has made practical advances!!!

Author bdub z ( ago)
he's never gonna forget gloves again if he touches that filler with the torch lol, especially on ac

Author vicky meyer ( ago)
Publication chicken therapy feed flow transform function exhibition ankle.

Author tjrsasea ( ago)
Hey guys! Support my photobook about Space titled Ethereal that will literally bring you out of this world on Kickstarter The campaign is ending very soon! Thank you! :)

Author Peter - John Jones ( ago)
ive clicked on this vid because the caption actually made me laugh due to my (low) understanding of welding aha

Author Nicholas Rapacciuolo ( ago)
Is it just me or do I want that nut bar

Author Matthew Linn ( ago)
You talk like cold welding cannot happen on earth in normal atmosphere. It happens a lot that is why we have to use antiseize some of the times.( I know that is not the main purpose of antiseize.)

Author Huemid ( ago)
The footage of Gemini looks like stop motion, was it a recreation of what happened or is the video sped up?

Author MyParkour121 ( ago)
"You have to heat them past their melting point" - ever heard of forge welding ? the temperatures are close to melting but still more than 100°C (Sorry I don't know the Fahrenheit scale) lower than melting.
please correct me if I'm wrong, it may be that with the plastic deformation of the steel the temperature at the welding surface rises above the melting point, but that I doubt. So as far as I know you can indeed weld steel without melting it.

Author cryo phile ( ago)

Author Protein Strands ( ago)
this is incredible

Author daft nord ( ago)
i just slightly cold welded two hard drive platters together. highly polished things can do it in earth atomsphere

Author Teodor Foca ( ago)

Author Ivan Quaglia ( ago)

Author Gradha Putra ( ago)
0:06 Science is about to hap.. hang on, different channel

Author King of Cannabis ( ago)
I wonder if Juno's jammed up fuel valve may have cold welded.

Author 10DBott ( ago)
cold welding seems to be the same as forge welding just without the heat and flux to keep the oxygen off

Author Devesh Dadhich ( ago)
"Manufacture Nanotechnology" Really? Did you mean manufacturing nanomaterials?

Author Anubhav Yadav ( ago)
best example of candy bar dude

Author Rylan Delap ( ago)
why wouldn't the same materials that aren't metal still cold weld when rubbed together in space?

Author Scott Hannan ( ago)
This really gave our astronauts a chance to test their metal/mettle.

Author Justin Murtagh ( ago)
Wow, Americans pronounce "Gemini" like that? Sounds so weird to me :).

Author The Sqoou ( ago)
Is cold welding synonymous with cold fusion ¿

Author Mike Sanchez ( ago)
payday is my favorite candy bar

Author Slizarus ( ago)
I wonder if Kerbals know to coat their metals.

Author Memawandpatrick ( ago)
Tfal then?

Author Kenneth Fung ( ago)
do the crystal structure of metal needed to be the same?

Author ThePilotPenguin ( ago)
Remember to put on your welding mask at 0:09

Author Ian Robinson ( ago)
man i love your channel. Thanks for this.

Author Vivien BERGOUGNOUX ( ago)
Sooooo NASA fanboy! You have been asked to reinforce the fakery of scientism agenda! Here is how selling out will cost you a LOT in a very near future. A future where people like you are going to be disregarded and discredited so harshly I will even feel bad. If it is intentional like Vsauce, we will know, if it is because of your lack of education and ability to understand the realm we live in then you still have a small window and come around explaining why this video along with other ones are pure propaganda and does not have any tangible content.
Time will tell

Author kairon156 ( ago)
I never heard of cold welding before. I know on earth Tungsten usually doesn't like sticking to other metals so I wonder if that would be a good one to use on space craft.

How big can we use cold welding? can 2 metal ingots be cold welded together? can we weld space crafts or stations using cold welding?

Author Matt Macken ( ago)
I understand why objects of different materials or alloys won't 'cold weld', but why won't materials other than metal fuse together is space? If you have two identical pieces of plastic, what about plastic, keeps them from sticking together? Plastic is just one example, you can insert other items in it's place, but the question remains.

Author Eleazar Barrios ( ago)
Gave us those cold welding tips like were going to be using them

Author Chirp Dee ( ago)
I thought the title said space weed, whoops

Author Quetzachapin ( ago)
Stupidest explanation EVER. CANDY BARS?

Author nom chompsky ( ago)
This is cool and all, but I clicked this vid to see the canadarm do some stick welding

Author Project³ ( ago)
Those candy bars look delicious.

Author Elranoaz ( ago)
I hate those peanuts it's freaking hard and often hurt me when i'm smashing it in my mouth .

Author Zebobez ( ago)
Hey, that's a Payday bar. I love those.

Author wonszlol ( ago)
Could cold-welding ever be utilized on a scale larger than the nano?

Author K. M. ( ago)
Doe s anyone know what this guy does for work, in real life, outside of youtube?

Author ron bergeron ( ago)
i know that your house, and you have poor taste in kitchen decore

Author TheRealestEver ( ago)
real life kerbals

Author Ray Davis ( ago)
The problem is with similar metals that slide past one another (solar panels, antenna, etc.), thereby scraping the oxide layer away.

Author Bike Talk ( ago)
What really happened is the cold in space shrank the metals and caused them to bind, nothing to do with cold welding, cold welding is welding without full penetration, e.g get two tight fitting steel tubes and put the outer one in fridge then slide into the smaller one, it won't work

Author gsantee ( ago)
mmm Payday....oh no...oh no! he dipped it in chocolate! its not right!!!
but tastes so good ( ͡° ͜ʖ ͡°)

Author James Estrada ( ago)
I so want a payday.

Author Jordan Beagle ( ago)
Homemade Oh Henry's, nice :D

Author ot4kon ( ago)
houston capcom. haduken!

Author Random Experiments International ( ago)
Very interestig story and facts! Nice video! :)

Author Evan Zhuo ( ago)
I have a candy bar, i have a candy bar... uuuggghhh long candy bar!

Author Barbarian UNO ( ago)

Author sitrilko ( ago)
Do clean metals in vacuum have a surface tension, like liquids?

Author Joe Love ( ago)
Are the reactions on the molecular level of cold welding metals in space actually the same as welding metal on Earth? Or is it more of a magnetic effect? Or is it a completely different reaction and we just call it cold welding when it really has nothing in common with welding other than the metals stick together?

Author Raw Gameplay ( ago)
I got a curiosity stream ad with veritasium in it

Author Deepak Sridhar ( ago)
During Gemini space venture, the whole crew was in a Studio! Look at the footage, looks like a setup!

Author JJLatBIM ( ago)
So could you cold weld without a vacuum? Could you just ultra-clean the metal surfaces in a gas that won't react with the metal and press them together?

Author Sven Jonkers ( ago)
but why doesn't gold have this gold welding on earth. Or does gold have a little oxide layer?

Author C Martinez ( ago)
Damnit I clicked on this video thinking it was "Wedding in Space"

Author mad kobra ( ago)
so do you need absence of atmosphere or gravity or both for cold welding?

Author Matthew Falcher ( ago)
Now I'm hungry

Author Dupy, Dziary, Muscle Cary. ( ago)
Really awesome information, that I somehow never heard of before. Tough the video was really boring..

Author Sam Biscits ( ago)
Science is so cool!

Author unlokia ( ago)
@ 05:07

_"3: Use gerbil coatings"_ (listen to pronunciation)


Author Rasydan ( ago)
Really interesting representation with that bar xD

Author Tyler Pfaff ( ago)
NASA=lies. the earth is flat

Author Tyler Pfaff ( ago)
you mean water welding in a dark pool right?

Author Elliott Shaffer ( ago)
is it possible to use outer space to host a true quantum computer.

Author sjbubbly ( ago)
Derek, it's galling. That's why there is anti-seize on fasteners. Second, using dissimilar metals can be a s***y idea due to galvanic corrosion (check galvanic series). That's why there are dielectric plastics. I think plastic coated metal on moving surfaces is the way to go if it can be done.

Author Luis Brudna ( ago)
Agora o vídeo está com legendas em português. Ative as legendas usando o botão CC do Youtube. ;-)

Author Ethan Snider ( ago)
Do space welders have to worry about delta p, like dive welders?

Author viperz888 ( ago)
He said he's busy and he'd rather not talk to us 😂

Author Argoon1981 ( ago)
never knew this was a problem or even a blessing learned something new today.

Author Vln Murthy ( ago)
I always wonder what the first second of the video is? That flash of light...🤔

Author Matthew McMahon ( ago)
That Tig welder in the beginning was not wearing gloves!!! Safety!

Author Evan Huff ( ago)
when he started cock fighting those two peanut butter bars I died 😂

Author Jason A Stevens ( ago)
earth is flat, video invalid.

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