 Bagaimana dengan pembentukan plastik? Ya, ya. Okey. Well, bit of background. I've been riding an electric unicycle around. And because I'm cheap, I need to get battery packs because they die eventually, right? And so, I mean sometimes they die and then I have to tear them apart and start replacing cells, right? And that requires a spot welding of these nickel strips onto the cells. And yeah. So, like I said, I was cheap. I tried to solder at first. And stuff like this happened. Slow motion. Yeah, stuff like that happened. And so, I needed a spot welder, right? And there are plenty of instructions online on how to make one out of a microwave oven transformer. And so being the cheap guy I am, I go and start making one instead of buying one, right? And so, I came across this link on Aliexpress which is a spot weld controller. It's literally set up so that you can wire a microwave oven transformer to it. Ya. It's good. I have tested it. It works. So, the way it works is that this little board here accepts AC power from this wire. Then this little transformer here is stepped down to nine volts alternating current. And that powers the board. It will rectify voltage and use it to power its own electronics, et cetera, right? And then, over here, it switches the primary side of the large transformer. So, it's basically like SSR. It switches a small amount of current and it waits for the wave to cross zero volts in order to switch. And this is the transformer. It's a microwave oven transformer. Originally, it's a step-up transformer, right? I have 240 volts to something kilovolts. And so, you rip out the primary coil. I mean, sorry. You rip out the secondary coil, keep the primary coil in place, and then wind your own wire which is this zero gauge wire. Ya. Zero gauge wire comes from downstairs. There's a shop at the corner there that sells it for quite cheap. Ya. Ya. Ya, this is a great location. So, ya. So, that's a step-down transformer and it converts 240 volts, 13 amps into 2 volts and many amps. Something like 1,000, maybe 800. Ya. Ya, so... Sorry? Drive or circuit? Ya. The drain... No, no, no. The controller is only 9... A 9 volt thing. Ya, ya. It's driven by the small transformer. The large transformer is what welds. So, after this red wire, it just goes directly to the probes. Ya, so... You all know what spot welding is? Okay. So, spot welding is also known as resistance welding. It's when you pass a huge amount of current through the two metals, through the joints that you are trying to make. So, once you are passing something like 1,000 amps, it heats up very quickly in a localized spot and it welds just that spot. So, we use it on lithium-ion batteries because it doesn't introduce too much heat into the battery. Because, you know, you heat the lithium-ion battery and it goes boom. Ya. So, ya. That's it. So, how much does it heat? Hmm? How much does it heat? Because obviously... It can melt? Ya, it can melt you. So, it's about... 800 degrees? 1,000 degrees? I don't know. It also softens this thing. So, ya. 1,000 degrees sounds about right. This is the spot welding probe. I got very, very lazy with making the spot welding probes. So, usually you get something like... I don't know. Something more atas-looking like this, right? But I was very lazy. So, I took this zero-gauge wire. It's a stranded wire. I stripped a bit of rubber. I stuffed the probe in and then I clamped it shut. Ya, it works. Yes. So, I can give a demo. Maybe I'll just disconnect in case. Oh, I should cover a bit of the functionality of this controller board. Alright. So, the controller board it comes with this rotary encoder thing which is also a button. So, you cycle between these six options. Time 1, current 1, racing, time 2, current 2, and welding. So, the first two options are the time and current of the first pulse. Then there's an interval and then time and current of the second pulse. And then the last button is to load and save profiles. So, why do you need two pulses? It's because when you press the metals together, they are hard and you cannot get a proper joint at first. So, you need up versus it softens. It gets closer and then you weld it properly. Ya, you can do that but it's not as good as a dual pulse. Ya, and this is a dual pulse controller. Also, from your point of view as a human, it's just one pulse. Correct. It's very fast. It happens within 100 to 200 milliseconds. Oh, and it's enough to Yes. Ya, that's right. And then after that, you can touch the joint and it's not hot. Oh, awesome. Ya. So... You tried touching the joint actually. Ya, I did. I burned myself once but that was because I did many-many joints in succession. I don't think you're supposed to do that. I think you're supposed to do... If you did that joint in succession maybe she didn't do that. Ya, so you weld, let it cool, and then you weld again. Ya, so that sort of thing. Ya. So... Right. So what is interesting is you know, stuff that's not documented is that Oh dear. When you play with a spot welder so much current goes through these wires that they start to push each other apart. And nickel strips lying on the table will also jumpa-jumpa-jumpa-jumpa. So this is not safety, you can't untang. No, it's unintentional. In fact, I think I will move my laptop away. What? Is this a kind of inductive factor? So you know your right hand rule? Ya. Current goes this way, magnetic field goes this way. Ya, ya, ya. So... Let's see. This is a nickel strip. You fold it a bit so that you can sort of get a joint. Put it in a clamp. And... So, ya. I have made one design floor with this. And that is that I need two hands to hold this and I need, like, my chin or something to hit that. Ya, it's... Ya, hang on, hang on. I'm getting ready. Okay. So, yes. Press the green button. Can I really press? Yes, yes, go ahead. That's it. It's cool? Ya. That's your weld. Questions? It's heavy, eh? Oh, it's here? Okay, okay. Okay, okay. You can consider. It's, like, so short. I mean, based on the picture, I expected to see, like, brace. Right. Ya, why is it so short? Okay, so... It's a spot welder and because I've wound so little... I mean, I've done so little windings through for the secondary coil, it only has two volts, right? Something like two volts. So, you know, your welding current is going to be two volts divided by a little resistance in the entire path. I wanted as thick a wire as possible, as short as possible. And... Oh, it's a problem. Ya, that's right. Ya. Also, I've already done quite a number of welds on this. I can show you the battery. Oh, shit. Sorry, sorry. It's screwed on right now. Can't show, can't show. Okay. Okay.