Making superconductors

This video has been sponsored by ExpressVPN. About two years ago, I think I was doing research for my ferrofluid project, and I ended up watching a short video about superconductors. I don't remember exactly what video it was or where I even saw it, but I do clearly remember that it blew my mind.

They showed that if a magnet is dropped on top of a superconductor, it just floats there like some anti-gravity magic. At first, I thought that it was just carefully balancing there or something, but it could be easily pushed around to different positions. On top of this, what was even cooler in my opinion, was that when it was gently nudged, it was able to just freely spin around.

After seeing this, I immediately went to Google to see how hard it was to make a superconductor myself. Based on what I saw, it seemed like it was possible, but it also seemed like it was really complicated. I procrastinated for the next year and a half until this past January when I decided to finally commit myself to it.

When I looked into it a bit more, I found that superconductors can technically be made from a lot of different materials. However, for most of them to work, they need to be cooled to ridiculously low temperatures. For example, just mercury can apparently be a superconductor, but only when it's lower than -269°C, which for me is just impossible.

The superconductor that I saw in that video though, was called a YBCO superconductor, and it didn't have to be nearly that cold. It only had to be lower than -181 °C, which I could easily do by just soaking it in liquid nitrogen. I did a bit more research, and I found that there were other ones that also worked with liquid nitrogen.

However, I couldn't find much info on how to make them, and from what I did find, they all seemed to be a bit more difficult. YBCO really seemed like it was the best option. I committed to making YBCO, and now I had to put together some sort of procedure.

Like before, I reached out to Google for help, and the first result that I got was probably the best one. It was a video by Ben over on the channel Applied Science, and he was able to make a working superconductor. He covered almost all the essential info about the process, and it was extremely helpful.

The only thing that I wanted to change was the final shape of the YBCO. Ben had just used a crucible as a mold, so it wasn't exactly the most beautiful-looking thing, but I wanted mine to be some nice and pretty pellets, just like I had seen in that video. In the description, he also gave a link to the full-length procedure that I assume he followed.

It was probably the most detailed procedure on the Internet, and it made everything seem relatively straightforward. I decided to do exactly what they did, except on a larger scale. However, when I actually sat down and started doing some calculations, I realized that none of their numbers made any sense.

YBCO is called YBCO because it's a combination of yttrium, barium, copper, and oxygen. However, it's also sometimes called yttrium-123 because of the ratio between the components. There's always one yttrium, two bariums, and three coppers.

In this case though, they don't seem to be using this 1:2:3 ratio, even though they say that they are. On top of this, they did a whole bunch of seemingly pointless calculations, and they also used a number that was blatantly just wrong. This isn't to blast them or anything though, because calculation errors happen all the time, but it meant I couldn't rely on what I had here.

It was very possible that the rest of the info was still good, and it probably was. But after seeing this, I really just didn't trust it. I scoured the Internet for a new procedure, and a few days later, I was thankfully able to find this one.

It wasn't nearly as detailed and it didn't have any photos, but it actually gave numbers that were accurate. Before I could actually get started, I had to buy a bunch of chemicals. The first two were yttrium oxide and copper nitrate, and I was able to find both of them on eBay.

I also needed barium nitrate, but I wasn't able to find it anywhere online. I unfortunately ended up just overpaying for it and ordering it from a chemical company. The last thing that I needed was citric acid, which is commonly used in food, so it was really easy to find, and I got two pounds of it from Amazon.

At this point, I had all the ingredients that I needed, but I started to worry about the purity of the eBay chemicals. The copper nitrate was all nice crystals and it looked okay, but I really wasn't sure about the yttrium oxide. The eBay listing said that it was over 99% pure.

However, you can never really trust those claims. Unfortunately, I was going to have to purify it, and the best way that I found was to convert it to yttrium nitrate. To do this, I added 200 milliliters of water along with about 100 milliliters of concentrated nitric acid.

I let it stir for a couple of minutes, and then I started adding some of the yttrium oxide. The amount that I added here was random, but when I eventually felt that it was enough, I turned on the hot plate. Right now, nothing was really happening, but when it got hot enough, the yttrium oxide suddenly started reacting with the nitric acid.

This quickly turned it all into yttrium nitrate, which, unlike the oxide, was soluble in water. This caused the solution to slowly clear up, and after this, I just kept adding the oxide whenever it looked like it was fading. It eventually got to a point where it stopped clearing up, and this meant that all the nitric acid was gone.

I then added a bit more nitric acid, just enough to destroy the extra oxide. This caused it to clear up again, but it was still a bit cloudy and there was a whole bunch of solid junk that was floating around. I had no idea what this was, and it was all just some sort of impurity.

It was apparently a good thing that I decided to clean it up. To get rid of it, I filtered it all through some cotton and Celite, and this left me with a nice and clear solution. I then put it all back on the hot plate and I got rid of most of the water.

I honestly didn't know exactly how much I had to get rid of, and I just went until it was roughly half the volume that I started with. After that, I took out the stir bar and I waited for it to cool to room temperature. I let it sit like this for a few hours, but nothing really happened.

I started poking at it a bit to force the yttrium nitrate to crystallize. I wasn't sure if this was going to work, but it did, and there were a bunch of small crystals that formed around the stir rod. I then gently stirred the whole thing and I let it sit overnight.

The next day, there was a whole bunch of yttrium nitrate at the bottom, and I broke it into smaller pieces. To separate it, I poured it all into a vacuum filter, and I was eventually left with some clean and fluffy crystals. It was all still covered in water though, and to fully dry it up, I put it all into a vacuum chamber that had some drying agent at the bottom.

I pulled a full vacuum on it and then I took it out a few days later. What I had now was some dry and crunchy yttrium nitrate. This, of course, wasn't the oxide that I had started with, and if I specifically needed it to be the oxide, part of the purification process would have been converting it back.

But conveniently, turning the oxide into the nitrate is actually the first step in a lot of YBCO procedures, including the one that I was following. This whole purification was just a slightly more complicated first step. At this point it was still a bit wet, so I put it all back into the vacuum chamber and I let it dry for a few days.

After this, I had some dry and pure yttrium nitrate, and now I could actually start making the YBCO. To do this, I started by adding 225 milliliters of distilled water, and I turned on the stirring. Then into this, I dumped in 72.

48 grams of the copper nitrate. It immediately turned a really nice blue and I waited for it all to dissolve. When I came back to it a few minutes later, it was still a bit cloudy, probably because there was a bit of copper carbonate in there.

This wasn't much of an issue though, and I just added a couple drops of nitric acid to convert it all into copper nitrate. This caused it to all quickly clear up, and the next thing that I added was 52. 27 grams of the barium nitrate.

This however, really wasn't very soluble, and I had to heat it a bit with the hot plate. I let it stir for about 20 minutes and it had gotten quite hot, but there was still a decent amount of solid stuff. This was fine though, and I just went ahead and added 38.

3 grams of the yttrium nitrate that I had just made. I then waited until it looked like all the yttrium had disappeared. However, exactly when that happened was a bit hard to tell because there was still so much barium floating around.

When it eventually seemed okay, I added the final ingredient, which was a bunch of citric acid. I let this stir for about 20 minutes, and then I checked the pH. The red color told me that it was quite acidic, and it was probably around a 1 or 2.

What I had to do next was neutralize this, and bring the pH up to between 6. 5 and 7. To do this, I had to use ammonia and I had just recently bought a fresh new bottle of it.

The moment that it was added, it started reacting and it turned a much darker blue. It also generated a lot of heat and it was causing some of the water to boil. I had to make sure to add it slowly.

After adding a decent amount, I let it stir for a few minutes, and I checked the pH again. It now looked like it was around 5, which was better, but I still had a bit to go. From here, I just kept adding small amounts of ammonia and checking the pH.

The first major reaction that was happening here was between the basic ammonia and the citric acid, and I was turning it all into ammonium citrate. It was also reacting though, with the yttrium, barium, and copper nitrate, and turning them into hydroxides. The copper and yttrium hydroxides then reacted with more ammonia to form dark blue complexes.

I don't think the barium was complexing with the ammonia though, and it was instead forming a complex with the ammonium citrate. However, I really don't know that for sure, and I had a very hard time finding any decent info about this reaction in general. It was really hard to tell with these cheap pH papers, but it eventually looked like it was between 6.

5 and 7. To see if all the barium had disappeared, I took out a small sample and it looked okay. There was a small amount of junk though, so I quickly poured it all through a coffee filter.

When this was eventually done I got rid of the funnel, and now it was time to turn all of this into the YBCO. To do this, I had to split it up into a bunch of smaller portions and I poured 50 milliliters into another beaker. I then turned on the hot plate and I waited for the water to evaporate.

About 30 minutes later, I was left with this nasty brown mess. Based on what I had read and seen, this was what I expected. I still wasn't sure though, and it was just so gross that I honestly started worrying that I had messed something up.

I actually started thinking that I was going to have to start over, but it turned out that I was just being impatient. At first, the sound caught me a bit off guard because it was way louder than I thought it would be. I also didn't think that it was going to be so slow or that it would grow like that.

It was a pleasant surprise though, and I honestly think that at least visually, it's one of the coolest reactions that I've ever done. When the reaction was over, the beaker was still very hot, and I put it somewhere to cool down. Then into a new beaker, I added 75 milliliters instead of 50.

I was trying to use more because I had to keep repeating this reaction for a total of about 500 milliliters. I was hoping that by using 75 milliliters, I wasn't overdoing it and that it could just make things go a bit faster. Now, in terms of what was actually happening here, it was called the citrate pyrolysis reaction.

Just before when I had added all the ammonia, it had turned all the metal nitrates into hydroxides, but it had also made ammonium nitrate. This was a really strong oxidizer, and all the ammonium citrate was a good fuel. When the temperature was high enough, it triggered a reaction between the two and it caused it to burn.

All the yttrium, barium, and copper hydroxides were mixed in here as well though, and the heat of the reaction caused them to decompose. It turned them all into their oxide forms, and it also made a lot of water vapor, which was why the side of the beaker kept fogging up. When I first did this reaction, I thought that it was making YBCO, but I don't actually think that's the case.

I think that it was mostly just making a really good mixture of the metal oxides. I was a bit worried that using the 75 milliliters might be a problem, but it turned out to be mostly fine. The only thing that I didn't like was that it grew out of the beaker.

In this run, it didn't end up being an issue, but in another one, it could grow weird and maybe cause some of it to fall out. I went back to doing it with 50 milliliters, and to make it go faster, I ran a couple others at the same time. It was fun and it felt like I was running a small little YBCO factory.

I was eventually almost done, but with the last little bit that I had, I decided to try something different. In all the other runs, there was a bunch of water vapor that clouded the beaker and it made it hard to see. I wanted to see if I could fix this by instead doing it in a dish.

It was definitely a lot clearer, but I knew that it was going to be a bit of a failure. There was just no way that it was all going to stay in the dish. What was worse though, was that this dish wasn't made of borosilicate glass, which meant that it wasn't great at handling big changes in temperature.

Despite this, I was hoping that it would still be able to survive, but it did not. Because it exploded before it was done reacting, I didn't trust the quality of the stuff that was made. Unfortunately, everything that I just made here was just garbage.

That didn't really matter though, because I had more than enough good stuff from all the other runs. What was interesting was that it looked like I had an insane amount of it, but it was just really fluffy. The moment that I just even barely touched it, it just collapsed.

I then mixed it around to reduce the volume even more, and I combined everything that I had from all the runs. At this point, like I said before, I don't think that I actually had any YBCO yet, and it was just a mixture of the yttrium, barium, and copper oxide. To turn it into the YBCO, it had to be heated to a very high temperature in the presence of pure oxygen.

Most procedures said that they used something called a tube furnace, but when I went online to buy one, they weren't exactly cheap. They were all way too expensive, and I figured that instead, I would have to modify my little tabletop furnace. This was exactly what Ben had done, and he had modified his furnace and rigged it to an oxygen tank, so it should have been okay.

With a bit more research though, I found some tube furnaces being sold on Alibaba that were way cheaper. I spent a while researching all the different models, and I ended up getting this one, which had a nice touchscreen. The total price was about $2,000 USD instead of $5,000 USD or even more, and I figured it was worth trying out.

I guess the only downside was that there weren't any reviews, and I didn't know if it was even going to work very well. I was excited when it arrived a few weeks later, but I also got a call telling me that it wasn't all in one piece. I was calling about your package.

Are you coming to pick it up? Yeah, I'm actually going to be there very shortly. Okay, the only problem is that it's damaged.

It's quite severely damaged. It seems that they shipped it in a crate and the crate has come apart. I'm not sure what you want to do.

You'd have to look at it yourself, I guess. After hearing this, I was pretty much expecting to just see a pile of rubble. However, it was somehow still completely fine and there was only one minor scuff on the bottom, which I was okay with.

I still had to make sure that it actually worked though, so I brought it back to the lab and I plugged it in. I then clicked the button, and it seemed to be totally fine. But then it suddenly turned off, and I started to smell something burning.

There was also some nice smoke coming out the back of it, which isn't something that you usually like to see with electronics. I was really disappointed, and I figured that it was damaged in shipping or something, but then I realized that it was entirely my fault. When I was ordering it, they asked if I wanted to run it on 120 or 220 volts, and I totally forgot that I said 120V.

I also forgot to tell them to put an American plug on it instead of the standard 220V Chinese one. Based on the plug and some terrible memory, I just assumed it was 220V and I plugged it into my 220V line. This was probably one of the dumbest mistakes that I've ever made, and it was very possible that I destroyed the furnace.

I honestly panicked a bit, and despite knowing not very much about electronics, I took it apart to see what was broken. The first thing that I found was this broken capacitor, which had popped open at the top of it. It had also spewed all of its capacitor goo onto the board that was above it.

The only other thing that was obviously dead was the voltage transformer. When I took it out, I could see that it was all melted. I assumed that I was going to have to change the capacitor and maybe some of the other things on the board, but I apparently got really lucky.

When I contacted the company, they were surprisingly super helpful and they told me that the part of the board that broke didn't actually matter. I technically didn't even have to repair this board at all, and all I did was take off the broken capacitor. Now, the only other obvious problem was the transformer, and with the help of my dad, I swapped it out for a new one.

We then plugged it in to the proper 110V socket, and it didn't immediately light on fire, which was a good sign. The real test though, was to actually turn it on, and I was genuinely really nervous. But by some amazing luck, the furnace was apparently saved.

I then did a few heating tests on it just to be sure, and it was completely fine. Apparently, luck was on my side and I didn't have to buy a new furnace or anything. It did take a few days to troubleshoot and fix everything though, which wasn't ideal.

But either way, I could now get back to the actual project and try to make some YBCO. To do this, I dropped a quartz tube into the furnace and I filled it with the oxide powder. I had no idea how much I could add, and I just put an amount that I felt was good and it wasn't really based on anything.

I then took out the piece of paper that was just being used to keep the end of the tube clean. After that, I slid in these end-piece things which would help seal the furnace and prevent the heat from leaking out. I then rigged the tube with some metal pieces that would let me attach the oxygen.

With all that done, I closed the furnace and I connected the oxygen line. I also opened the oxygen tank and I adjusted the flow rate. I spent a lot of time trying to figure out how much oxygen I had to use, but I couldn't find any decent resources.

This was based on nothing, and I just went with 50 milliliters per minute. After that, I turned on the furnace and I checked the heating curve to make sure that it was the right one. I had set this up beforehand and it was pretty simple.

Over an hour, it would be slowly heated to 920°C and then held there for 10 hours. After that, it would be slowly cooled at 50°C an hour until it was room temperature. This whole process should cause the oxide powders to fuse together and form the YBCO.

The slow cooling part would also let it crystallize, which was very important. I went ahead and started it, and I came back to check on it about an hour later. At this point, it was at the max temperature of 920°C and on the outside, it didn't look like much was going on.

If I looked in from the side though, I could see that it was glowing red. It was going to have to cook like this for another nine hours, and then it would be slowly cooled over 18h, and I just left it overnight. The next day, I opened the furnace, and the first thing that I noticed was that the powder was a lot blacker and that it had also shrank.

I then took off most of the metal attachments on the sides and I pulled out the white blocks. To get it out of the tube, I carefully pushed it with a glass rod. What I had now was definitely more dense than before, but it was still pretty fluffy and fragile.

In theory though, this should have been YBCO, and I wanted to see if it were able to superconduct. I poured some liquid nitrogen into a dish and I waited for it to cool down. I then dropped in a piece and I waited for that to cool as well.

When everything looked nice and cold, I dropped a piece of a neodymium magnet on it and it clearly didn't work. This was honestly a bit disappointing, but it also wasn't surprising. The first problem was that it was still too light and fluffy and there wasn't actually very much here.

The second, and probably bigger issue though, was that I don't think it was oxygenated enough. YBCO always has the same ratio between the yttrium, barium, and copper, but it's able to vary between six and seven oxygens. However, it's only able to superconduct in the seven form, and what I had probably still contained a lot of the six form.

To fix both these problems, the YBCO is usually compressed into pellets and then put back into the furnace and heated again with oxygen. That was exactly what I had to do next. To do this, I started by adding it all to a mortar and I ground it into a fine powder.

I think in Ben's video after he did this, he just put it all into a crucible and heated it again and it ended up working. However, like I said before, I wanted mine to be some nice hockey-puck-looking things. To make this happen, I needed a die set which would let me crush it and shape it.

I also needed a hydraulic press, and I had bought both of these things over a year ago. Basically, I had everything that I needed, but I had no idea how much powder to actually use, and I just ended up putting in all of it. Then on top of it, I added a metal spacer thing and a pushing rod, and I brought it over to the hydraulic press.

For safety reasons, I put the gate in front just in case something decided to explode under the high pressure. I then started pressing it and I brought it up to about eight tons. I let it sit there for a few minutes and then I released the pressure, and I took off the bottom piece.

I could see the nice pellet that I had made, and now I had to get it out. I flipped the whole thing over, put another piece on top, and I pressed it until the rod was all the way through. At first, I was pretty happy with it, but when I got a closer look, it wasn't as beautiful as I thought.

Also, when I tried to move it, a small piece of it broke off. I think this happened because I was, unfortunately, missing a piece of my die set. I was supposed to have two of those metal spacers where one of them would have been put underneath the powder.

I think this just really helps keep everything together when the whole thing is flipped over and the pellets getting pushed out. I then carefully tried to put it onto a small piece that I cut from a fire brick. Unfortunately though, a much larger piece ended up breaking off and this just made me want to re-make the whole thing.

However, when I flipped it over, it didn't seem that bad. I decided to just roll with what I had and I loaded this back into the furnace. Now, as I said before, one of the major purposes of this second heating step was to oxygenate it as much as possible.

Another very important thing that I was doing though, was something called sintering. The pellet that I had now was just a bunch of powder crushed together, but in the high heat, the particles should fuse. Then, as it slowly cooled, it should crystallize, which, like I said before, was very important.

When it was done, it looked exactly the same, and like before, I carefully pushed it out with a glass rod. The pellet that I had now was way stronger than before, but I was used to it being super fragile, so I was still really careful with it. Regardless of all that though, what I had at this point should have been the final YBCO.

Now, I was really anxious to test it out and to see if it actually worked. Like before, I filled the dish with some liquid nitrogen and I dropped in the pellet, and I waited for it to cool down. I then got a small magnet and I carefully dropped it on top, and it actually worked.

It was floating, just like how I saw in the video, and I was honestly really surprised that I was able to do it on my first real attempt. Also, this whole time, I was still a bit worried about the purity of my yttrium and copper nitrate, but they were clearly fine. Up until now, I've referred to the floating magnet as anti-gravity magic, but unfortunately, it isn't anti-gravity, and it also isn't magic.

When superconductors were first discovered, it was believed that they were basically just super good at conducting. It was found that they had effectively no resistance and they could move an electrical current with almost perfect efficiency. However, it was then discovered that they were a bit more complicated than that.

It was also found that superconductors were almost perfectly diamagnetic. This meant that instead of being attracted to a magnet, they were strongly repelled. In my case, when the magnetic field of the magnet is applied to my little YBCO pellet, an opposing magnetic field is induced in the YBCO, and it pushes back on the magnet.

This induced field perfectly cancels out the field of the magnet and it causes it to float. This effect alone though, would just repel the magnet and cause it to fall off, but it doesn't because there's actually another unique effect that's going on at the same time. The crystal structure of the YBCO isn't perfect and small defects allow a bit of magnetic field to still get through.

This causes small magnetic flux tubes to form and they act like tethers and they hold the magnet in place. This is called flux pinning, and unlike the diamagnetism, the force is actually attractive. Even though the magnet is just floating there, it's still connected to the YBCO, and if I push it around, the pellet moves with it.

Now, another thing to check is to see what happens if I put the magnet on before cooling it. When I did this, it didn't do anything for a while, and then it suddenly jumped into the air. This is called the Meissner effect, and it's unique to superconductors.

It happens because at first, the magnetic field is able to pass through the YBCO. This changes though, the moment that it gets colder than the critical temperature and it becomes a superconductor. It suddenly becomes almost perfectly diamagnetic and it starts expelling almost all of the magnetic field.

This first run turned out to be way more successful than I expected. The pellet that I had made though, was ugly and I still had a bunch of oxide powder. The next thing that I wanted to do was use the rest of it and to make several, hopefully nicer pellets.

To do this, I figured I had to just more or less repeat the exact same process. This time, I felt that it was probably fine to fill the tube a lot more, and I added about 10 times the amount. However, this was only about 70% of the powder that I had left.

After this, I would still have to do one other run. When it was done I dumped it all out, and it was definitely a lot blacker than it was before. However, it looked like it still had some unreacted brown stuff in it.

When I crushed it up it looked okay, but I didn't like this at all, and I decided to run it again. I put it all back into the furnace, and I ran it for another 28 hours, and this time, it was much better. Looking at it now on video, it's hard to tell, but in person, it was definitely a lot blacker.

I then ran the last 30% of the powder, and I also did it twice, and I combined it all together. After that, I went back to my fire brick and I cut out a much bigger piece. I sized it to be the biggest thing that I could fit in the furnace, and it looked like it could hold five pellets.

That was how many I was going to make. Now, in terms of pellet thickness, I had to decide how big I wanted them to be. For the first one, I just crushed what I had, and it ended up being about 1.

9 millimeters. But now, knowing that it was 1. 9 millimeters, and that it weighed 3.

85 grams, I could calculate the amount that I needed for any thickness. The 1. 9 millimeters did seem to be okay, but I felt that it was just a bit too thin and fragile, so I decided to make it 3 millimeters instead.

I also found that spacer piece that I was missing, and I was able to make some really nice pellets. After making four of them, I decided for the last one that I would make it a lot thicker. This one was 6 millimeters, and I wanted to see if it could float the magnet higher.

I again loaded it all into my furnace and I ran it through a cycle. When it was done, they all looked good, and I was pretty excited that I now had five nice superconductors. I had to test them though, just to make sure they all worked, so I soaked one of them in liquid nitrogen.

I then got the same magnet that I used before, and I was disappointed to say the least. I thought that maybe it was just this one in particular, so I tried all the others and the big one, but they all completely failed. This was a very sad result, and I wasn't exactly sure what had gone wrong.

The one thing that I knew though, was that my base oxide powder was good because I did have one successful run with it. To me, the only possible difference was the level of oxygenation. I had used a lot more powder this time, and I think there was just some trouble getting it all fully oxidized.

I figured that there was literally only one thing that I could try, and that was to oxidize it a bit more. To do this, I had to turn all my beautiful pellets back into a powder, and I started by just trying to crush them by hand. It worked okay to break it up into small bits, but these bits were way too hard and I wasn't able to crush them into a powder.

Instead, I threw them all into a small blender. Then after that, I screwed the top on and I ran it for several minutes. This gave me a relatively fine powder, which I loaded back into the furnace.

The powder this time was way denser than before, so I was able to spread it out all in a thin layer at the bottom. I ran it overnight for the same 28-hour cycle, and the next day, it looked about the same as before. I then crushed them all back into pellets, and I again made four of them that were 3 millimeters.

This time though, the last one was more like 4. 5 millimeters instead of 6. This happened because while reprocessing it, I somehow lost 4 grams of the YBCO.

I really have no idea where it went because it's not like I dropped any, and I think that some of it might have just gotten vaporized in the furnace. But either way, I then centered them, and I was really hoping that this was the last time I was going to have to put them in the furnace. I took them out the next day, and like before, I thought they looked really nice.

That didn't really matter, though, if they didn't work, so I took one of them and I soaked it in liquid nitrogen. When it seemed cold enough, I then got my magnet, and I was honestly really nervous that it was just going to fall and hit the YBCO. Also, if this didn't work, then I'd have literally no idea what went wrong or how to fix it.

Thankfully though, it did end up working and I honestly can't say how relieved I was to see this. Like I just said, if it didn't work, I'd have no idea what to do next, but I guess it really was just the oxygenation. I then tested each one to make sure that they were all good, and I also tried out the big one.

One thing that I noticed though, was that none of them floated the magnet as high as that first successful run. Also, the big one seemed to actually be weaker. To me, this meant that even though it was working now, it was still probably lacking oxygen.

I really didn't want to have to run them in the furnace again, but I decided to do it one last time. I didn't do them all though, and I just loaded up the big one and one smaller one. This time, I also decided to run it for much longer and instead of 10 hours at 920°C, I did it for 24.

I honestly didn't expect too much to change, but there was actually a huge difference. On the smaller one, the magnet floated significantly higher than before. It was also able to hold a much larger magnet, which I thought was pretty impressive.

The big one was now actually more powerful than the smaller ones, and it had no problem holding the bigger magnet. It could even keep it up when it was on the side and it had enough clearance that it was still able to rotate. At this point, I felt that I was more or less done, and I was really happy with how it all turned out.

However, there was something important that I still had to try. Up until now, I had always put a magnet above the YBCO, but it should also be possible to do it the other way around. To try this out, I set up a little magnet track, and when the YBCO was fully cooled, I dropped it on.

It was actually able to hold itself up, and when I pushed it, it moved along the track without falling off. I was also able to shake the whole thing and bounce it back and forth, and it felt like I was playing pong. The moment that it warmed up though, and got above the critical temperature, it would just fall off.

Now, there's one final thing. I wanted to try adding ferrofluid to the magnet while it was floating above the YBCO. I'd seen this in a few videos, and I just thought that it was cool.

I also thought that it was an interesting crossover between my own projects, because I could use the ferrofluid that I had made myself. I had made this ferrofluid over a year ago now, but it's still perfectly good. While I was doing this, I realized that the one big thing that I still hadn't made myself was a magnet.

For my next big project, I've decided to try and make my own neodymium magnets. However, I haven't even started on that, and I have no idea when it's actually going to happen. As I've said before, projects like these take months to put together, and they can often cost quite a lot.

When I started this channel, I could barely even afford a beaker, and I never thought that I'd be able to do any of this. But thankfully, between Patreon and sponsors, these big projects are actually possible. This one in particular was sponsored by ExpressVPN, which is a service that keeps your information private when you're browsing the Internet.

It does this by encrypting all your data before sending it out and then routing it through secure servers. This prevents anyone, including your Internet service provider, from seeing what you're doing or spying on the websites that you visit. For me though, besides privacy, I mostly use it to access content that isn't available here in Canada.

There are a lot of streaming services that I'm just not able to use, and some of them, like Netflix, have a selection that changes depending on where you are. With just a few clicks though, I can choose a server in another country and access the selection that they get there. Now, if I go to Netflix, I can see that I have the British selection.

It has a whole bunch of different shows and movies, and it's the only one that has It's Always Sunny in Philadelphia, which is one of my favorite shows. But with all that being said, if you're interested in privacy and breaking geo-restrictions, I recommend checking out ExpressVPN. You can do this by going to expressvpn.

com/nilered, and right now, they're giving three extra months for free when you sign up for a 12-month plan. They also have a 30-day money-back guarantee, and there's a link in the description. But with all that being said, I think this is officially the longest video that I've ever made.

I hope you guys liked it, and bye. As usual, a big thanks goes out to all my supporters on Patreon. Everyone who supports me can see all my new videos, at least 24 hours before I post them to YouTube.

You'll also get access to all the older videos that I had to take down. If you support me with $5 or more, you'll get your name at the end like you see here.