WEBVTT - What is cold welding? 0:00:08.440 --> 0:00:11.039 Hey, Kelly, how are things going on the science farm? 0:00:11.400 --> 0:00:13.680 You know, they're going pretty well, but we have some 0:00:13.880 --> 0:00:17.159 old pipes and they've been sailing and so, you know, 0:00:17.239 --> 0:00:19.520 renovating the bathroom in the kitchen. We're pretty low on 0:00:19.600 --> 0:00:21.799 why to do list, but suddenly they went to the 0:00:21.840 --> 0:00:26.040 top and so there's been lots of renovating projects happening. 0:00:26.560 --> 0:00:29.520 Ooh, does that mean lots of opportunities to show your 0:00:29.600 --> 0:00:32.479 kids how to use power tools? Circular saws and arc 0:00:32.520 --> 0:00:33.839 welders and all that good stuff. 0:00:34.280 --> 0:00:37.320 Uh, there's lots of opportunities for me to play with 0:00:37.400 --> 0:00:41.280 power tools, many different kinds of saws. No arc welders yet, 0:00:41.840 --> 0:00:45.880 but generally the kids are not playing with the power. 0:00:45.600 --> 0:00:48.239 Tools, not until they hear this episode and then they 0:00:48.280 --> 0:00:49.600 start asking for their turn. 0:00:50.040 --> 0:00:51.600 This is why my kids don't get to listen to 0:00:51.600 --> 0:00:52.199 your podcast. 0:00:52.960 --> 0:00:56.560 Man, how can you consider yourself a good parent if 0:00:56.560 --> 0:00:58.360 you don't share this podcast with them. 0:00:58.760 --> 0:01:01.760 I'm pretty sure that the number one rule of parenting 0:01:01.840 --> 0:01:05.280 is keep the kids alive, and I'm pretty good at that, 0:01:05.920 --> 0:01:07.600 and that just seem to be tied to them not 0:01:07.640 --> 0:01:08.759 listening to your podcast. 0:01:10.000 --> 0:01:28.200 Fair point. Hi, I'm Daniel, I'm a particle physicist and 0:01:28.240 --> 0:01:31.520 a professor at UC Irvine, and I want everybody's kids 0:01:31.560 --> 0:01:32.760 to stay happy and healthy. 0:01:33.120 --> 0:01:37.160 I'm Kelly Wieder Smith. I'm a parasitologist. I'm adjunct at 0:01:37.240 --> 0:01:40.319 Rice University, and I also want kids to stay happy 0:01:40.400 --> 0:01:42.920 and healthy, which probably means no power tools before the 0:01:42.959 --> 0:01:43.440 age of ten. 0:01:45.000 --> 0:01:48.240 Ooh, you hear that Kelly's kids tenth birthday, you're getting 0:01:48.240 --> 0:01:48.960 power tools. 0:01:49.240 --> 0:01:51.240 Oh no, that's only a couple months away from one 0:01:51.280 --> 0:01:56.240 of them. I meant twenty twenty. 0:01:56.680 --> 0:02:00.200 Wow, that was pretty quick backpedaling right there. You know, 0:02:00.200 --> 0:02:03.240 eventually they got to learn some useful skills, so arc 0:02:03.280 --> 0:02:04.680 welding could be in their future. 0:02:04.880 --> 0:02:07.120 You know, she's really good with the screwdriver, and I 0:02:07.160 --> 0:02:09.440 feel like I've done my part. She could also make 0:02:09.480 --> 0:02:11.919 a little circuit. She did that for the Talent Show 0:02:12.680 --> 0:02:15.119 and it had little light up eyes and the mascot 0:02:15.160 --> 0:02:17.600 of her school and it was pretty cool. I'm doing 0:02:17.600 --> 0:02:18.560 a great job, Daniel. 0:02:20.200 --> 0:02:23.480 You're doing a bang up job for sure, and so 0:02:23.760 --> 0:02:27.239 welcome to the podcast. Daniel and Joor explain the universe, 0:02:27.360 --> 0:02:29.840 in which we try to do a bang up job 0:02:29.960 --> 0:02:34.359 of welding your brain to the universe, making those connections 0:02:34.360 --> 0:02:37.240 between everything that's happening inside your skull and all the 0:02:37.240 --> 0:02:41.399 physics of the universe, the black holes, the tiny particles, 0:02:41.440 --> 0:02:45.200 the galaxies, the arc welding, everything that's going on out there. 0:02:45.240 --> 0:02:48.440 We want you to understand it. No topic is too big, 0:02:48.520 --> 0:02:51.160 no topic is too small, no question is too weird, 0:02:51.280 --> 0:02:55.240 no idea is too bunkers for us to consider, because 0:02:55.280 --> 0:02:58.520 our goal is to make sense of the whole universe. 0:02:58.880 --> 0:03:00.959 My usual co host he can't be here today, but 0:03:01.000 --> 0:03:02.600 I'm very happy to be joined by Kelly to talk 0:03:02.600 --> 0:03:05.359 about today's amazing and fun topic. 0:03:05.800 --> 0:03:08.040 I'm excited to be here. You know how, I think 0:03:08.080 --> 0:03:12.280 you and I just had a podcasting aniversary, didn't we. 0:03:12.360 --> 0:03:14.799 It's been like two and a half years or two, 0:03:15.800 --> 0:03:17.799 I don't know, it's been a while. I'm excited. 0:03:18.760 --> 0:03:21.359 Oh no, I'm embarrassed. I haven't been keeping tracks. I'm 0:03:21.400 --> 0:03:25.079 totally unaware of our anniversary. I apologize. I should have 0:03:25.120 --> 0:03:25.920 gotten you something. 0:03:26.160 --> 0:03:28.800 Well, that's you got me a really interesting topic to 0:03:28.840 --> 0:03:30.720 talk about. Oh, thank you. 0:03:30.919 --> 0:03:33.760 Yes, that must have been my subconscious plan of what's 0:03:33.800 --> 0:03:34.960 what it was the whole time. 0:03:35.200 --> 0:03:38.360 Yes, the two year anniversary is the cold welding anniversary. 0:03:38.560 --> 0:03:42.520 M Well, congratulations on two years of being on the podcast. 0:03:42.560 --> 0:03:44.400 We love all your contributions. 0:03:44.400 --> 0:03:45.560 Oh, I love being here. 0:03:45.840 --> 0:03:48.760 Thanks awesome. And sometimes on the podcast we talk about 0:03:48.840 --> 0:03:51.880 quantum mechanics. Sometimes we talk about black hole, sometimes we 0:03:51.960 --> 0:03:55.000 talk about planetary orbits in the future of our star. 0:03:55.560 --> 0:03:58.840 And sometimes we talk about the everyday physics and science 0:03:58.880 --> 0:04:01.360 that is around us, stuff that makes up our lives, 0:04:01.400 --> 0:04:04.120 how it works, and how hard it is to understand 0:04:04.240 --> 0:04:07.360 even the everyday normal stuff in our universe. 0:04:07.640 --> 0:04:08.640 It never gets easier. 0:04:09.520 --> 0:04:11.720 It's sort of amazing the complexity of things that we 0:04:11.760 --> 0:04:14.920 see around us, rocks and blueberries and ice cream, and 0:04:14.960 --> 0:04:17.440 it's incredible that we can understand how that stuff all 0:04:17.480 --> 0:04:20.760 comes together from the tiny little particles that are inside it. 0:04:20.880 --> 0:04:23.000 The buzzing and tuing and frowing of all those little 0:04:23.040 --> 0:04:26.880 bits somehow weave themselves together into this incredible experience we 0:04:26.960 --> 0:04:30.320 have where things seem solid or liquid or gaseous, that 0:04:30.400 --> 0:04:32.680 we know that that actually all just bubbles up from 0:04:32.720 --> 0:04:35.000 the tiny little particles inside them. 0:04:35.279 --> 0:04:37.720 I'm glad you're confident that we understand the world, because 0:04:37.720 --> 0:04:40.800 as a biologist, I'm way less confident. But we'll go 0:04:40.920 --> 0:04:41.240 with it. 0:04:41.920 --> 0:04:44.680 You know, I was recently doing college interviews, and one 0:04:44.680 --> 0:04:47.200 young lady told me she was really interested in biology 0:04:47.360 --> 0:04:49.839 because she thought it was cool how you could explain 0:04:49.960 --> 0:04:54.240 everything using the smallest bits around us, the cell. And 0:04:54.279 --> 0:04:56.120 I was like, well, it is very cool how the 0:04:56.200 --> 0:04:59.159 cell comes together to make complex biology. But you know 0:04:59.240 --> 0:05:02.040 you can go further than that, right, you can dig deeper. 0:05:04.000 --> 0:05:05.880 You leave her alone. She's on the right track. 0:05:06.120 --> 0:05:08.880 I almost convinced her to do particle physics, but she 0:05:09.000 --> 0:05:11.359 was like, nah, she wanted to study stuff that was 0:05:11.400 --> 0:05:15.000 more relevant to our lives. Good for her, but there 0:05:15.040 --> 0:05:18.040 are still lots of deep mysteries remaining about this fairly 0:05:18.080 --> 0:05:22.000 pedestrian idea. Everything is made of particles. Those particles follow 0:05:22.080 --> 0:05:24.839 simple rules, and how those bits bang up against each 0:05:24.839 --> 0:05:27.479 other and stick or don't stick and repel makes up 0:05:27.520 --> 0:05:30.360 our whole world. Why some things are shiny, why some 0:05:30.400 --> 0:05:33.160 things are sticky. We think that those are all emergent 0:05:33.240 --> 0:05:36.560 properties from those little particles and the rules that they follow. 0:05:36.960 --> 0:05:38.919 But it's complicated. It's not like if you give me 0:05:38.960 --> 0:05:41.799 the location and velocity of ten to twenty nine particles, 0:05:41.920 --> 0:05:44.440 I can tell you exactly how they're going to behave, Oh, 0:05:44.480 --> 0:05:46.240 this thing's going to flow or this thing's going to 0:05:46.279 --> 0:05:49.479 conduct electricity because it's a lot of particles. It's too 0:05:49.520 --> 0:05:53.320 many for us to understand, which is why chemistry is 0:05:53.360 --> 0:05:56.200 still a thing, right, which is a reason, the reason, 0:05:56.200 --> 0:05:59.000 the reason we don't just have particle physics as the 0:05:59.040 --> 0:06:00.520 only science in the universe. 0:06:00.760 --> 0:06:05.240 I mean, that would not be as interesting. But yeah, 0:06:05.760 --> 0:06:10.120 I remember I took stochastic differential equations in college, and 0:06:10.200 --> 0:06:12.760 I was just like, how do we know anything about 0:06:12.800 --> 0:06:15.440 the universe? Ever, this is also complicated, and. 0:06:15.960 --> 0:06:19.039 It is incredible because the universe seems chaotic. All those 0:06:19.040 --> 0:06:21.800 tiny little particles are so dependent on other tiny little particles. 0:06:21.960 --> 0:06:24.800 It's incredible that anything emerges. But one of the great 0:06:24.800 --> 0:06:29.040 philosophical mysteries of science is that simple stuff does emerge. 0:06:29.320 --> 0:06:32.000 Balls seem to follow simple trajectories, even if we can't 0:06:32.080 --> 0:06:35.520 understand the tiny particles inside them. You can make chicken 0:06:35.560 --> 0:06:39.560 soup without understanding quantum gravity. The universe is understandable at 0:06:39.560 --> 0:06:43.120 all these different layers, which means there are fascinating questions 0:06:43.160 --> 0:06:46.880 and interesting mysteries at every level of science. You know, 0:06:47.240 --> 0:06:52.600 studying galaxies, studying people, studying cells, studying funguses, and studying 0:06:52.640 --> 0:06:56.000 the tiny little particles questions to be asked at every level. 0:06:56.360 --> 0:06:58.960 Not sure we'll ever understand people, but well we'll do 0:06:59.080 --> 0:07:00.000 our best and keep. 0:07:00.120 --> 0:07:03.000 And forward exactly. And so one of the topics we 0:07:03.120 --> 0:07:06.840 love thinking about is how materials work. Why protons and 0:07:06.880 --> 0:07:10.080 electrons come together to make one thing conduct electricity and 0:07:10.120 --> 0:07:13.200 something else be transparent and something else be opaque. How 0:07:13.200 --> 0:07:15.880 does that all emerge from the tiny little particles that 0:07:15.920 --> 0:07:18.840 are inside them? And there's so many different aspects of 0:07:18.880 --> 0:07:22.000 these materials we can explore, like how you stick them 0:07:22.000 --> 0:07:24.920 together to build stuff? How does the Eiffel Tower come 0:07:24.960 --> 0:07:27.840 together from all those individual bits of steel? 0:07:28.280 --> 0:07:31.920 Gorilla glue? 0:07:32.240 --> 0:07:35.320 No, wow, you just invented an entire country over there. 0:07:38.000 --> 0:07:40.160 I mean, it's a really good glue. You can get 0:07:40.160 --> 0:07:41.440 it in a can and spray it. 0:07:41.760 --> 0:07:43.120 Are you saying if they were going to build the 0:07:43.120 --> 0:07:46.560 Eiffel Tower today, they would use guerrilla glue instead of welding. 0:07:47.040 --> 0:07:49.160 Probably, I don't know. You'll have to tell us about welding. 0:07:49.240 --> 0:07:50.640 Then I'll make my decision at the end. 0:07:51.360 --> 0:07:53.480 Well, today in the podcast, we are going to talk 0:07:53.520 --> 0:07:56.600 about welding, how it works, how you can stick stuff together, 0:07:57.000 --> 0:07:59.800 and how you can possibly do it without even heating 0:07:59.840 --> 0:08:02.080 things up in a way that could be helpful for 0:08:02.120 --> 0:08:06.040 space industry and could be safe for even Kelly's children. 0:08:06.200 --> 0:08:10.560 Oh all right, you've got my attention. Maybe my oldest 0:08:10.600 --> 0:08:13.920 can listen to the you know, second part of this discussion. 0:08:14.200 --> 0:08:16.600 So today in the podcast, we'll be asking the question 0:08:21.960 --> 0:08:26.280 what is cold welding? So this is a topic a 0:08:26.320 --> 0:08:28.800 bunch of listeners wrote in to ask me about what 0:08:28.960 --> 0:08:31.600 is the physics or the chemistry or just the science 0:08:31.720 --> 0:08:35.400 of cold welding. How could it be possible to stick 0:08:35.440 --> 0:08:39.720 stuff together without melting it down first, and could this 0:08:39.840 --> 0:08:43.120 potentially be a way to build things in space? 0:08:43.600 --> 0:08:46.280 So, you know, when you proposed the topic of cold 0:08:46.320 --> 0:08:50.040 welding to me, I could not remember a time when 0:08:50.080 --> 0:08:52.280 I had heard this phrase, And so my first thought 0:08:52.360 --> 0:08:55.000 was was it like sticking like pieces of gum together? 0:08:55.080 --> 0:08:58.719 And then I'm like, no, welding, welding specifically refers to metal, right, 0:08:58.720 --> 0:09:01.199 It's like putting two pieces of met together, is that right? 0:09:01.360 --> 0:09:01.880 Yeah? 0:09:02.080 --> 0:09:05.160 Yeah, yeah, And so then I was like, I don't know, 0:09:05.280 --> 0:09:07.160 but but I hear it has to do with space, 0:09:07.200 --> 0:09:08.880 So I'm gonna have to I'm gonna have to go 0:09:08.960 --> 0:09:12.440 with that. So let's see if your listeners are more 0:09:12.640 --> 0:09:14.840 clued into the world of welding than I am. I 0:09:14.880 --> 0:09:17.000 bet they are, so. 0:09:16.920 --> 0:09:19.520 Thanks very much to everybody who answers these questions for 0:09:19.559 --> 0:09:23.120 the podcast. If you would like to contribute your uninformed 0:09:23.160 --> 0:09:26.600 speculation for the episode, please don't be shy. Write me 0:09:26.679 --> 0:09:31.679 to questions at Danielandjorge dot com. Everybody's welcome, So think 0:09:31.679 --> 0:09:34.120 about it for a moment before you hear these answers. 0:09:34.280 --> 0:09:36.559 What do you think cold welding is and how does 0:09:36.600 --> 0:09:38.920 it work? Here's what listeners had to say. 0:09:39.720 --> 0:09:43.280 Well, cold welding can't work by heating up two metal 0:09:43.400 --> 0:09:46.520 sources and melting them together, but it could create a 0:09:46.640 --> 0:09:50.280 chemical reaction that causes them to melt together. So my 0:09:50.320 --> 0:09:52.520 guess is it's not actually fire, but it's some sort 0:09:52.520 --> 0:09:53.439 of chemical. 0:09:53.480 --> 0:09:58.199 Maybe it is using a chemical reaction to fuse two 0:09:58.320 --> 0:10:02.320 things together to rearrange them molecules. It reminds me of 0:10:02.360 --> 0:10:06.440 the old farmers in Vermont would attach wrought iron gate 0:10:06.520 --> 0:10:10.120 latches to granite posts by boring a hole in the 0:10:10.120 --> 0:10:12.319 granite and sticking the gate latch in there, and then 0:10:12.400 --> 0:10:15.560 pouring some sort of a powder that would create a 0:10:15.559 --> 0:10:19.160 reaction and fuse the two together. I've tried to cut 0:10:19.200 --> 0:10:23.559 them out many many, many years later, and it's impossible. 0:10:23.640 --> 0:10:24.920 It's sort of just one thing. 0:10:25.760 --> 0:10:28.079 Well, those were two great answers, And to be honest, 0:10:28.200 --> 0:10:33.720 I hadn't heard about farmers attaching iron latches using a 0:10:33.800 --> 0:10:37.679 powder to connect it to granite. Like that's awesome. I've 0:10:37.720 --> 0:10:39.560 got to find an excuse for how to do that 0:10:39.600 --> 0:10:41.400 on the farm, even though right now I don't think 0:10:41.400 --> 0:10:41.920 I need to. 0:10:42.240 --> 0:10:44.640 I think that sounds like farm magic, you know. I 0:10:44.640 --> 0:10:46.760 think he'd run into some magicians and they have some 0:10:46.880 --> 0:10:49.280 like spells and powders, and they're able to like fuse 0:10:49.320 --> 0:10:51.960 things together. I think we need to dig into this. 0:10:51.960 --> 0:10:54.120 This could be like a whole revolution in science. 0:10:54.400 --> 0:10:56.120 So you hadn't heard of that before either. 0:10:56.360 --> 0:10:59.200 Vermont farmer magic. Noila had not heard of that before. 0:11:01.600 --> 0:11:05.080 I can imagine it being pretty obscure Vermont farmer magic. 0:11:05.160 --> 0:11:07.760 But that's not that far away from the Salem witches. 0:11:10.000 --> 0:11:12.640 Those farmers. You gotta be careful. You gotta be careful 0:11:12.760 --> 0:11:16.160 using your powers out there where everybody can see you. Yeah, 0:11:16.160 --> 0:11:18.080 but this doesn't seem to be something a lot of 0:11:18.080 --> 0:11:20.720 people have understood. And frankly, I was a little surprised, 0:11:20.800 --> 0:11:23.360 Kelly that you didn't come across it in all of 0:11:23.400 --> 0:11:26.760 your deep, deep research about space settlements. 0:11:27.120 --> 0:11:30.480 You know, I have literally thousands of pages of notes, 0:11:30.640 --> 0:11:35.040 and my mind retains one percent of what I write down, 0:11:35.520 --> 0:11:38.120 because I figure, why memorize it if I could just 0:11:38.520 --> 0:11:42.240 you know, control what it control f for my search 0:11:42.360 --> 0:11:44.520 term and then see what I wrote down in the past. 0:11:44.840 --> 0:11:47.320 So I bet I read about cold welding at some point, 0:11:47.400 --> 0:11:50.240 but it did not stay in my internal hard drive. 0:11:50.360 --> 0:11:52.680 Well maybe it turns out it won't be crucial for 0:11:52.720 --> 0:11:55.439 a space settlement, after all, we'll find out. 0:11:56.280 --> 0:11:59.160 So I asked a silly I won't say stupid, a 0:11:59.240 --> 0:12:02.320 silly question at the beginning. You know, could it be 0:12:02.360 --> 0:12:04.360 like sticking two pieces of gum together? And you told 0:12:04.440 --> 0:12:10.640 us no, it requires metal. What else are the very 0:12:10.760 --> 0:12:12.520 very basic facts of welding. 0:12:12.679 --> 0:12:16.200 Yeah, so before we talk about specialized cold welding, let's 0:12:16.240 --> 0:12:19.880 just talk about normal vanilla hot welding. I guess, and 0:12:19.920 --> 0:12:22.560 this is basically sticking two pieces of metal together. You 0:12:22.559 --> 0:12:24.920 want to build the Eiffel Tower, you want to build 0:12:24.960 --> 0:12:28.000 a bicycle, you want to build a tank, you want 0:12:28.000 --> 0:12:30.320 to build an airplane, all this kind of stuff. You 0:12:30.400 --> 0:12:33.520 got to use welding. Welding is basically the way that 0:12:33.559 --> 0:12:37.840 we corillatly stuff together in the modern world. 0:12:38.160 --> 0:12:43.160 So I'm doing a bathroom renovation and luckily when I 0:12:43.200 --> 0:12:46.679 opened up the wall, there were no copper pipes, because 0:12:46.760 --> 0:12:49.520 then I was gonna have to solder, and I don't 0:12:49.559 --> 0:12:51.800 know how to solder, but I would have learned. Is 0:12:51.840 --> 0:12:57.880 soldering welding because it's like that little silvery thing that 0:12:57.920 --> 0:12:59.840 you unroll and you heat up and you put on 0:12:59.880 --> 0:13:03.800 the copper. That's metal too, right, So does that count? 0:13:03.920 --> 0:13:07.000 Yes, so that does not count as welding. Soldering and 0:13:07.040 --> 0:13:10.400 welding are two different things. So welding is when you 0:13:10.480 --> 0:13:14.240 melt two pieces of metal, so the metals themselves join 0:13:14.400 --> 0:13:17.199 become like one piece. So you got two objects you 0:13:17.280 --> 0:13:20.079 want to stick them together. You actually melt the edges 0:13:20.120 --> 0:13:23.679 of both of them. Soldering is different soldering. You have 0:13:23.760 --> 0:13:26.640 a lower temperature filler, something which melts at a much 0:13:26.720 --> 0:13:30.000 lower temperature that basically acts as glue and bonds to 0:13:30.040 --> 0:13:33.240 the two surfaces. But you don't actually melt the two 0:13:33.320 --> 0:13:35.800 things you're sticking together. So you got two pipes you 0:13:35.840 --> 0:13:38.400 want to stick together, you can solder them together. By 0:13:38.440 --> 0:13:42.040 melting some filler material which sticks them together, or you 0:13:42.080 --> 0:13:45.160 can actually weld them by melting the two pipes and 0:13:45.160 --> 0:13:47.760 sticking them together when they're liquid, so when they cool, 0:13:47.800 --> 0:13:49.640 you get those chemical bonds between them. 0:13:50.160 --> 0:13:51.880 But soldering is still cool because you get you used 0:13:51.880 --> 0:13:55.480 a bload. I was kind of torn when I opened 0:13:55.559 --> 0:13:57.680 up the walls and there was pets. Part of me 0:13:57.760 --> 0:14:00.280 wanted to solder, part of me did, But anyway, okay, 0:14:00.760 --> 0:14:01.880 I'm getting a soft track. 0:14:01.840 --> 0:14:04.040 And soldering somebody. You can do an electrical laborate. You 0:14:04.080 --> 0:14:06.800 have that special solder material which you touch to the 0:14:06.800 --> 0:14:10.040 tip of the soldering iron. It just like instantly liquifies, right, 0:14:10.240 --> 0:14:13.280 super cool stuff, and that stuff you use because it 0:14:13.320 --> 0:14:16.120 liquifies very very easily, and then it cools very quickly 0:14:16.559 --> 0:14:20.400 and becomes solid again. So that's soldering. But welding is different, right. 0:14:20.720 --> 0:14:22.680 Welding is when you really want to join these two 0:14:22.720 --> 0:14:25.880 materials and you do it by some combination usually of 0:14:25.920 --> 0:14:27.280 heat and pressure. 0:14:27.600 --> 0:14:31.800 Okay, and I'm guessing that we've been welding. It's got 0:14:31.840 --> 0:14:36.680 to be after we get access to fire. How much 0:14:36.760 --> 0:14:39.080 after we get access to fire before we're welding. 0:14:39.200 --> 0:14:42.640 Yeah, welding technically is something we've been doing for thousands 0:14:42.680 --> 0:14:47.320 of years. Essentially, blacksmiths invented welding. They notice you got 0:14:47.400 --> 0:14:50.160 two pieces of metal, you heat them up and pound 0:14:50.200 --> 0:14:52.960 them hard enough. They will join a lot of the 0:14:52.960 --> 0:14:56.240 stuff that's been connected together to make basic swords and 0:14:56.280 --> 0:14:59.040 tools for farms and all this stuff that blacksmiths have 0:14:59.080 --> 0:15:03.320 been making for thousands of years. They called that forge welding. Basically, 0:15:03.440 --> 0:15:05.920 heat it up and hammer it hard and you will 0:15:05.960 --> 0:15:09.480 get that fusion, that connection between the two materials that 0:15:09.560 --> 0:15:11.120 tells you that they are now one. 0:15:11.720 --> 0:15:16.000 Okay, So they're using like a furnace, Is that the 0:15:16.040 --> 0:15:19.000 most typical way or a blowtorch? Is that the most 0:15:19.040 --> 0:15:21.440 typical way to get the heat that you need to 0:15:21.520 --> 0:15:22.680 combine two metals. 0:15:22.880 --> 0:15:26.000 Yeah, exactly. And when my dad retired from Los Almo's 0:15:26.080 --> 0:15:29.360 National Labs, he actually took up blacksmithing as a hobby. 0:15:29.720 --> 0:15:31.680 I was pretty sure he was like preparing for the 0:15:31.800 --> 0:15:34.200 end times. He thought, like, what would be a useful 0:15:34.200 --> 0:15:38.280 skill to have if civilization collapsed, and he decided blacksmithing 0:15:38.360 --> 0:15:41.840 would be useful, And so he got a little furnace 0:15:42.200 --> 0:15:43.960 and he would go to the dump and like pick 0:15:44.000 --> 0:15:47.560 up scrap metal, you know, like truck suspensions and all 0:15:47.600 --> 0:15:49.800 sorts of stuff, and he would melt it down and 0:15:49.840 --> 0:15:51.880 hammer it into shapes. And he made all sorts of 0:15:51.880 --> 0:15:55.800 stuff from like towel hooks to his own spears and 0:15:55.840 --> 0:15:56.600 stuff like that. 0:15:57.120 --> 0:15:58.360 Whoa, that's awesome. 0:15:59.160 --> 0:16:02.480 It was pretty cool until half the town burnt down 0:16:02.520 --> 0:16:05.120 in a forest fire, which is a real tragedy. And 0:16:05.160 --> 0:16:07.800 then the neighbors were a lot less keen on him 0:16:07.840 --> 0:16:11.120 having like a thousands of degrees furnace in his garage 0:16:11.200 --> 0:16:14.480 spewing up sparks into the dry woods. So he got 0:16:14.520 --> 0:16:18.560 shut down. Yeah, reasonable, reasonable, yep. 0:16:18.800 --> 0:16:20.760 But said, hey, do you know what turneski? 0:16:21.240 --> 0:16:22.000 I don't. Who's that? 0:16:22.000 --> 0:16:24.600 I think he's the current blacksmith that loaves Alabos and 0:16:24.600 --> 0:16:29.680 he's a friend of mine. Oh, right, back and off, okay, okay, 0:16:29.920 --> 0:16:31.760 So I was trying to get you to talk about electricity. 0:16:31.960 --> 0:16:34.880 Yeah, but blacksmithing is an ancient form of welding, right, 0:16:35.040 --> 0:16:36.960 You heat it up, you squish it together, and what's 0:16:37.000 --> 0:16:39.320 happening there is that the metals on one side and 0:16:39.360 --> 0:16:42.120 the metals on the other side are bonding together, and 0:16:42.160 --> 0:16:44.040 so there's really no distinction there. And that makes a 0:16:44.160 --> 0:16:48.640 very very strong connection. Right. But in the late nineteenth 0:16:48.680 --> 0:16:52.360 century we invented arc welding. We had electricity now, and 0:16:52.400 --> 0:16:55.920 see we could more efficiently deliver energy than just like 0:16:55.960 --> 0:16:58.880 sticking the whole thing in an oven, which also isn't 0:16:58.880 --> 0:17:01.200 possible if you don't have a big enough oven. You 0:17:01.200 --> 0:17:03.360 want to weld together two I beams, you don't want 0:17:03.360 --> 0:17:04.960 to have to stick the whole thing in the oven 0:17:04.960 --> 0:17:07.240 and then hammer them together. You want to only heat 0:17:07.280 --> 0:17:09.119 at the spot that between them that's touching. 0:17:09.600 --> 0:17:13.440 So what is more dangerous a giant furnace operating at 0:17:13.600 --> 0:17:18.600 intense heat or electrifying metals and working with fads. Kid 0:17:18.640 --> 0:17:20.879 one is not allowed to listen to the episode up 0:17:20.920 --> 0:17:23.280 to this point yet, let's see where we get to. 0:17:24.880 --> 0:17:27.199 But our welding is actually really cool because it basically 0:17:27.320 --> 0:17:31.520 makes a circuit. You're running electricity through the metals, and 0:17:31.560 --> 0:17:35.199 because the metals are not perfect conductors, there's some resistance 0:17:35.240 --> 0:17:39.000 to them, and resistance means heat resistance. You're turning electrical 0:17:39.119 --> 0:17:42.800 energy into thermal energy. Like the way a light bulb 0:17:42.840 --> 0:17:46.399 works is you're running electrical current through something which is 0:17:46.400 --> 0:17:48.800 a resistorance. It's gonna heat up and then it's going 0:17:48.880 --> 0:17:51.800 to glow. So the reason the metals get hot is 0:17:51.840 --> 0:17:54.520 the same reason that a light bulb glows. 0:17:54.359 --> 0:17:57.040 Ah, And so we just don't let it get out 0:17:57.040 --> 0:17:59.320 of control because you don't want your light bulbs burning 0:18:00.400 --> 0:18:00.879 or melting. 0:18:01.000 --> 0:18:04.240 That's right. And so in arc welding, what you're doing 0:18:04.320 --> 0:18:07.520 is creating a circuit, and then you're passing that electricity 0:18:07.840 --> 0:18:10.680 from a stick which arcs onto the spot that you're 0:18:10.720 --> 0:18:14.800 trying to weld, passes energy through that and then completes 0:18:14.840 --> 0:18:17.800 the circuit. And so you just power that electricity back 0:18:17.840 --> 0:18:20.240 and forth. You can be DC, you can be acy, 0:18:20.680 --> 0:18:23.119 all sorts of varieties of it. It was meant that 0:18:23.160 --> 0:18:25.639 in the eighteen hundreds when people were learning about the 0:18:25.680 --> 0:18:26.920 power of electricity. 0:18:27.240 --> 0:18:30.560 You know, you've got me wondering now, fun tangent. So 0:18:30.680 --> 0:18:34.159 the first the first space walk ever conducted by a 0:18:34.160 --> 0:18:39.200 woman was a sptlanasub Atskaya, and she welded in the 0:18:39.280 --> 0:18:42.320 vacuum of space for the first time. So do you 0:18:42.359 --> 0:18:47.080 think that she welded with heat or electricity? 0:18:47.600 --> 0:18:50.280 I suspect that was an arc welding, right, because the 0:18:50.280 --> 0:18:53.320 heat generation from like a blowtorch might require combustion with 0:18:53.400 --> 0:18:57.080 the atmosphere respect that was probably arc welding. 0:18:57.160 --> 0:18:59.520 Yeah, oh I should have known that. As soon as 0:18:59.520 --> 0:19:01.600 you started saying it, I was like, oh, of course. 0:19:02.000 --> 0:19:04.600 But anyway, all right, so fun, Yeah, there you go. 0:19:04.720 --> 0:19:07.639 But hold on, that sounds super dangerous. You have this 0:19:07.760 --> 0:19:11.400 like arc welding in space. I mean that could easily 0:19:11.480 --> 0:19:14.800 rupture a suit or cause some damage. So that seems 0:19:14.840 --> 0:19:15.439 crazy to me. 0:19:15.760 --> 0:19:19.600 Well, you know what's infuriating she is this like hypercompetent, 0:19:19.680 --> 0:19:23.600 incredible cosmonaut. And there's this movie called Solute seven that 0:19:23.680 --> 0:19:25.920 came out in Russia and it's sort of like Solute 0:19:25.920 --> 0:19:29.840 seven is almost their equivalent to our Apollo thirteen. So 0:19:29.960 --> 0:19:32.639 Solute seven like they had a problem I think it 0:19:32.720 --> 0:19:35.680 was with the solar panels and the power ran down, 0:19:36.119 --> 0:19:37.840 so they had to send somebody up there to try 0:19:37.840 --> 0:19:40.320 to fix it and get it back online. But at 0:19:40.320 --> 0:19:43.680 the beginning of the movie they create this scene where 0:19:43.720 --> 0:19:48.040 Setlanasovitskaya is welding in space, which happens, but she gets 0:19:48.160 --> 0:19:50.520 a welding burr in her glove and she's starting to 0:19:50.600 --> 0:19:54.600 lose pressure and her male colleague needs to pull her 0:19:54.640 --> 0:19:57.920 back into the station because she just like I don't know. 0:19:57.960 --> 0:20:01.000 It's like losing her composure. And that didn't happen. She 0:20:01.080 --> 0:20:03.720 did a great job of welding. She didn't get a 0:20:03.720 --> 0:20:05.840 burr in her glove. She didn't need to be saved 0:20:05.880 --> 0:20:09.120 by a man. But that's how the movie starts, and 0:20:09.520 --> 0:20:14.399 that made me very frustrated. Tangent done. Oh and the 0:20:14.440 --> 0:20:17.920 rest No, no, almost done, Tangent almost done. The other 0:20:18.160 --> 0:20:19.960 big lie in the movie is that they need to 0:20:19.960 --> 0:20:22.440 get up there to get the station started again because 0:20:23.160 --> 0:20:25.520 the shuttle, the Americans are going to set off the 0:20:25.520 --> 0:20:28.199 Shuttle and they want our technology, so they're going to 0:20:28.240 --> 0:20:33.000 put the Salute seven space station in the shuttle's cargo 0:20:33.080 --> 0:20:37.080 bay and take it back to Earth to steal our technology, 0:20:37.520 --> 0:20:42.439 which it wouldn't fit. That didn't happen, but that's like 0:20:42.480 --> 0:20:44.280