Melt Metals in the Microwave | The Ultimate Guide

in this video I'll show you how to melt Metals in your microwave there's a real life example where I made brass scissors that are as useful as a butter knife in a sword fight is it possible to make brass Scissors by only using a microwave a vacuum cleaner and a 3D printer I joined these 3D printed scissors with a graphite pencil core that way I won't need to drill any holes because most of time I use plaster of Paris for my metal casting projects I like it but it's not great for casting small holes it can easily break and you can end up with a holeless scissors this video is a short clip from a tutorial I just published on my channel if you want to learn how to melt Metals in your microwave check out the video in description [Music] so what do you need to start melting Metals first thing you'll need is a microwave it's just an ordinary microwave the only difference is that most of times I use it flipped on the side second thing you'll need is a crucible but not just any Crucible it needs to be made out of silicon carbide and the last thing you need is an insulating chamber it will let The Crucible reach temperatures high enough to melt metals like aluminum brass copper and even cast iron yep it's that simple silicon carbide absorbs microwaves and turns them into heat maybe absorbs is not a most scientifically accurate term to use but you get a point and that's where the chamber comes in you need to insulate The Crucible so you could trap all that heat and raise the temperature the chamber is made from ceramic fiber blanket also known as cable when you work with ceramic fiber make sure to wear a respirator so here I have ceramic fiber blanket we'll be doing what I call the rolling method for that you'll need a cylinder that's a little bit bigger than the crucible that you'll be using we'll cut a strip of ceramic fiber that's a little bit taller than The Crucible and by the way make sure your knife is sharp and keep that sharpener close first thing we'll do is cut one end of the strip in an angle and now we can start wrapping as you can probably imagine the cylinder can be anything that works a food can a jar and so on when desired thickness is achieved we'll cut the other end in an angle ceramic fiber comes in different thicknesses the one I use is a 25 millimeter sheet so the first chamber was three layers thick and this one only two layers so it's around 50 millimeters before wrapping we'll be using a captain tape to wrap the chamber and as you can see it comes in different sizes make sure that the captain tapes long term temperature resistance is at least 250 degrees Celsius or higher so next step is wrapping the chamber with a captain tape it will take a few sheets of ceramic fiber and we'll put the chamber on top make sure that the smoothed side of the chamber is facing up and then we just remove the extra material find this cutting somewhat satisfying I'm gonna flip it around and remove one of the sheets because I can't count two is more than enough for this small chamber and then we just join everything together with more Captain tape next we'll cut out a circle using a cylinder as a guide I will put it inside of the chamber assuming you have space if you have a blow torch I recommend heating up the inside of the chamber if you don't own a blowtorch don't worry about it it's fine the next step is pretty much the same that we did before but this time we're making the base I like to stick the edge of the captain table to the chamber it helps to hold it in place while we do the wrapping next step is adding some feet to keep this thing simple we're just gonna make these ceramic fiber and Captain tape pillows sometimes I use four other times three next step is making the bottom of the chamber and top of the base nice and smooth for that we'll be using a sanding glass that I'll show you how to make in a second I like the hot glue the glass to the table it works very well and when you're done it can be easily removed with some alcohol so we'll start with a piece of glass in this example I'll cut a glass Circle obviously you don't have to do that just use the glass as it is if hot gluing is not an option you can also use a cling film to stop the glass from moving just make sure the glass is clean if you want you can use a sandpaper to wet sand the glass or alternatively you can use another piece of glass or a drinking glass with a flat bottom to sand the main glass with some silicon carbide and water you will need silk and carbide to make The Crucible anyway so we're using the same material that you'll need later but just for different purpose in this example I'm actually using coarser grit silicon carbide because I have it but the fine grit will also work now we can use the sanding glass to smooth in the bottom of the chamber by mashing the layers together with the glass and the Chamber with some water and start meshing it only took me a minute to make it nice and smooth it's normal for the hole to start closing at the top or the bottom depends how you look at it more you sand more it will close all you do is cut it open with a sharp knife and then just use your fingers to shape it to your liking and then we do the same thing with the base the only difference when you need to check on progress make sure you slide the base off the glass do not lift it because it's like a suction cup the pulling action can separate the layers and make the base less firm next step is what I call microwave drying we'll microwave the chamber until the most water evaporates if there's a lot of water present you can take out the chamber and wipe microwave walls there's no more condensation on walls and the Chamber feels dry so now we'll do the same thing with the base if the base grows a toad skin don't worry about it you can dry sand it on glass at this stage don't worry about the base looking perfect when you wrap it with a captain tape it's normal for it to curve up so after wet sanding and microwaving it might not look as good as you want to don't worry about it it will fix itself later that is you will next we'll blow torch the surfaces to make them a little bit harder and again if you don't have a blow torch just skip the step if you happen to burn the edges of the captain tape make sure to cut off that burnt part by burning the captain tape to a charcoal level you can create an arcing Point arcing is when you put a sharp metallic object in the microwave and then you see a lightning show [Music] because of arcing the captain tape will heat up in that one point and it will keep heating up and smoldering so it can lead to something like this at this point you could use the chamber already but you risk in Crucible sticking if it's heated up too much not only it's a hazard when you're Crucible it's full with molten metal it's also annoying so what options do we have what are the options is Kiln wash you mix it with water and brush it onto the base you can also brush it onto the chamber you'll see me doing it in another example and then you just microwave dry it and the last step would be heating up The Crucible if you have made one already the first time you use the chamber it will get quite hot there's still some water trapped inside from sanding and Kiln wash the chamber is hot but I can easily take it out without gloves and by the time I set up the camera it was already too hot to handle without gloves unless you hold it by the top Kiln wash worked but I'll definitely need to add another layer and if you can't find gilwash here's one way to make your own for this recipe you'll need Kaling clay aluminum oxide and optional some pigment I mixed 50 of Kalin with 50 of aluminum oxide and I added a little bit of pigment shake shake shake shake shake shake shake your Kiln wash because of the pigment we ended up with a light gray Kiln wash not white so it's easier to see when you brush it on after microwave drying it the gray has pretty much disappeared and as I mentioned before I also like to apply some Kiln wash onto the bottom of the chamber but I usually dilute it with water okay let's try it out it's normal for the kill mush to crack from all that heat ceramic fiber will sink in here's a base that's been used quite a lot and it's been covered with a kiln wash a couple of times that's why I said not to worry about making perfectly flat base because it will not stay that way you have better chances of making the base flat if you resend it after it has been used a few times this time it came out much flatter and again don't worry about perfection I also like to sand the chamber and I don't bother reapplying Kiln wash there's enough Kiln wash soaked into the fibers a reminder how it looked before sanding and here's after let me show you one more way to make The Crucible non-stick and it's by using only aluminum oxide or aluminum if you prefer aluminum oxide on its own is great to stop your Crucible from sticking but it's not very brushable that's why it's better to mix it with kale and clay and by the way Kaling Clay on its own is also an option but they won't have those non-stick properties it will work to some degree if we only use aluminum oxide Under The Crucible and we don't cover the bottom of the chamber and top of the base with Kiln wash these surfaces can start to deteriorate they are kind of hard but they could be harder now it's not always an issue sometimes it can stay hard or it can Harden once you start melting metals and it can also depend on ceramic fiber sheet I had batches of ceramic fiber that were not great they were way too soft so next step is optional you can use it if you need it here's a way how to harden ceramic fiber by using boric acid solution so what's the boric acid solution well it's boric acid mixed with some water that's all it is let me show you how I do it we're gonna grab a scale and we're gonna wait some water next we'll add five percent of boric acid so in this case five percent from 400 that's 20. we're gonna heat it up until boric acid dissolves next we'll pour the boric acid solution into this spray bottle but first we need to make sure that liquid is not too hot I suggest using between five and ten percent of boric acid if you use more than 10 percent boric acid will start to recrystallize rapidly once the water starts cooling down and your spray bottle can clog up you can avoid the bottom of the chamber where the boric acid solution and then just microwave dry it depending how concentrated is your solution you might need to do it a few times I suggest not overdoing it because that can create other issues next we need to burn the boric acid to harden the surface you can see the flame turning green from the boric acid [Music] [Applause] gonna make aluminum oxide slurry by mixing it with water and then I applied it in a spot where The Crucible will go after microwave drying it it's hard enough to not fall off but it's not exactly glued to the base let's see how well it works before I show you how to make your own Crucible let's watch another short style video an award on how you can support this channel I've been using this Ender free S1 Pro 3D printer for last few months for all of my metal casting projects geekbank sent me this printer and gave me a coupon code that you can use to get this printed cheaper before we continue let me show you a real life metal casting example I'm gonna cast this egg cup in Copper I'm Gonna Mail this pipe in a microwave so I can make a copper a cup I 3D printed an egg cup that I designed I also designed these what I like to call Anchor points with the anchor points I can easily attach the filament to the model they're basically just Spruce to help the Metal Flow this video is a part of tutorial that I just published on my channel so if you want to know how to melt Metals in an ordinary microwave check out the video foreign [Music] [Applause] [Applause] [Applause] [Music] let me show you two ways to make a crucible the first one I call the glass method you'll need some fine grit or almost powder like silicon carbide we'll be using a drinking glass as a mold fill it up with silicon carbide to know how much you'll need we'll add between 8 and 10 percent of sodium silicate sodium silicate is also known as water glass here's a piece of cured sodium silicate mixed with some food coloring maybe that's why it's called water glass I use 37 water glass anything between 37 and 40 percent should give you similar results the reason I mention it because there are products out there that claim to be water glass but in reality it's a very diluted product so we have added the water glass now we just mix it properly we'll put it into the glass bit by bit pressing down with a tool of your choice to be clear this is not the tool of my choice but it will do for this demonstration I prefer the 3D print a press that fits the glass so you can make The Crucible nice and tight then we just carve out the center I like to use my fingers to shape The Crucible unless the glass is very tall then I call a tea I'm here to help will microwaved in full power until the glass shatters once cold carefully remove the remaining glass you can clean it up with different kinds of sanding tools I call it the stage one you could use The Crucible at this stage but maybe you shouldn't if The Crucible hasn't come out strong enough it could split in half during the use that said more often than not I will use smaller crucibles at this stage but maybe not with as much metal in them to be honest I don't remember when was the last time I had a crucible fail at the stage one but then again I have practiced a lot and I know what to look for so it's up to you if you want to use The Crucible at this stage just remember the risks and whatever you do it's on you one more thing if you do decide to use Crucible at stage one make sure to heat it up in the chamber before you use it to melt metals we will wrap The Crucible in ceramic fiber sheet and I'm only using a half sheet or so we'll use two rubber bands to hold that ceramic fiber sheet tightly wrapped we'll microwave it until The Crucible turns glowing red the rubber bands will break and shoot away from The Crucible now let it cool be careful The Crucible can be still hot even if the ceramic fiber feels cool to the touch we will scrape off ceramic fiber and be careful this action produces a lot of ceramic fiber dust so wear a respirator now we have a crucible that's much stronger let's try it out by melting two eight millimeter aluminum cable crimps they weigh 24 grams [Applause] and here's how The Crucible looks like after one time of use the same the second way to make The Crucible I call the freezing method you can download two different size molds from my patreon page and don't worry they're free you don't have to be a patron unless you want to let me clarify these modes you can 3D print with everything you need to make a crucible so first thing we do is screw on that little lid and then we just put together rest of the mold just like before we will mix silicon carbide with water glass for this small mold we'll need 100 grams of silicon carbide give or take and then between 8 and 10 percent of water glass then we fill the mold step by step and use the tools provided pressing down the silicon carbide as tight and as good as you can if you're making The Crucible on a hot summer day be aware that the water glass can start hardening pretty quickly so it's better to do it when it's not that hot putting the water glass in the fridge before you use it can help thank you we'll put it in a freezer for a few hours time to open it up we'll be using an allen key to unlock the inside mold keep twisting and pulling if you don't have an oven you can leave it on the table to harden naturally for a few hours and then you'll heat it up in a microwave to finish hardening it doesn't have to be super hot so in this case it's approximately 200 degrees Celsius if you do have an oven I suggest to use it preheat it put the Frozen Crucible inside and turn up the oven another method is to microwave the Frozen Crucible on low power step by step I usually cover The Crucible with a plastic cup that has holes drilled in it and then I remove the cup after a few Cycles I keep microwaving The Crucible little by little for example 10 seconds on 30 seconds off this method works but remember low power and step by step or you risk in messing up The Crucible our crucibles have reached stage one to take them to stage two it's all the same microwave wrapped in ceramic fiber let me demonstrate what happens when Crucible doesn't reach the glowing great temperatures as you can see the ceramic fiber hasn't really stuck to The Crucible it has only stuck a little bit not a lot of hardening has happened if you can remove the ceramic fiber that easily and here's the opposite this Crucible was microwaved for a little bit too long but that's it it's fine it's still gonna do the job look how shiny it is so which method is better the glass or the Frozen mold I think you should start with a glass method crossable because it's easier for a beginner and your crucibles will come out much stronger even at stage one unless you did it way too thin or you didn't do a good job impressing the silicon carbide into the glass mold don't get me wrong the freezing method crucibles are also great but it takes more practice to make them sort of fail proof listen there are so many things I could tell you about microwave metal melting so many steps were replaced with alternative ways to do things so this project would be easier faster and safer to replicate and I think we succeeded I can make everything the chamber the base and The Crucible in under an hour I know I know I practiced a lot so I might not be the best example this is where I'm going with this if if you find a value in this video do me a favor press the like button because it really helps the channel and if you haven't subscribed consider subscribing and ringing the bell I'll be publishing a lot of metal casting examples in YouTube shorts formats the reason our chamber is so effective is because of materials we use I have seen people making microwave Kilns and doing microwave metal melting with materials that are not that great so they end up with Chambers or Kilns that are not very efficient let me show you what I mean I pre-melt it 24 grams of aluminum or two of those eight millimeter rope crimps to melt this much aluminum takes around four and a half minutes in a crucible that's cold [Music] [Applause] let's repeat the experiment with the same Crucible and same chamber but this time I'll put a fire brick inside of the microwave and I'll microwave it for even longer let's give it 6 minutes because I was not watching the microwave I didn't hear the timer going off so I ended up microwaving for 6 minutes and 20 seconds so that's around 40 percent longer than before despite the fact that we microwaved it longer it was not enough to melt the metal so what happened the fire brick absorbed a good portion of the microwaves and it heated up in some parts it has reached almost 100 degrees Celsius that's why it's important to select materials that are microwave friendly materials that don't heat up too much in a microwave or heat up a little bit so you saw me melting some metal in 4 minutes and 30 seconds not bad but it's also not the best we can do melting times can depend on the power of your microwave size of your Crucible chamber and even the shape of the metal going back to the power it's not just the power on the paper the magnetron can also become weaker with the time it can wear out that's why if you buy an Old Second Hand microwave you don't really know what you're getting it happened to me a few years ago with this old microwave that I bought only because it looked big in the picture you can guess how that turned out it did work and I kept using it until I tried another microwave and realized that it can melt Metals much faster despite it being less powerful on the paper to give you a rough idea melting half Crucible of aluminum would probably take between five and eight minutes same amount of brass probably between 8 and 14 minutes obviously there's too many variables the biggest aluminum piece I have done to date is probably this one and it weighs around 80 grams now it's not massive by any means but it's also not tiny and in case you're wondering what it is I will publish an article about it on my patreon page if there's enough interest the biggest brass piece I have ever cast is probably this one it's a failed cast well it could probably be saved but I haven't done it and it was supposed to be a scotch tape dispenser and it's pretty heavy it waits just under 900 grams it took me between 25 and 30 minutes to melt that much brass one of the reasons why it took so long was because I had to Top Up The Crucible microwave metal melting at least in this setup is not the best for topping up crucibles yes you can melt cast iron and even stainless steel but don't expect to do it in large quantities you can check out my YouTube short where I made a cast iron Mario melting Metals with a melting point that high will significantly reduce the lifespan of your Crucible chamber and the base it's also possible for The Crucible to soften because of these extreme temperatures it has only happened to me once or twice when melting stainless steel The Crucible took an whole shape because I was holding it with tongues and then it cooled down in like three seconds taking its new shape if you struggle to melt those higher melting point Metals you can always insulate your Crucible let's talk about safety is it okay to flip the microwave on the side I have never had any problems and I have used a lot of microwaves there's nothing in a microwave that will stop working only because it's flipped on the side and I only base it on my own experience each microwave is different so if you're not sure don't do it but you might not need to flip it on the side this small chamber fits fine in this 30 liter microwave one of the reasons why I do flip it on the side is because of these microwave Kilns that I use to burn out plaster molds and what about microwave energy escaping because you turned your microwave on the side well that should not happen but if you're worried you can always get one of these microwave leakage detectors why do I make my Chambers so thin if you do a quick meltdown you will not benefit from having a thicker chamber in fact it could be the opposite yes I said ceramic fiber is microwave friendly but only to the point it also heats up a little bit so if you make your chamber massive you're also adding extra material that will eat all those microwaves and leave less for The Crucible in other words using too much ceramic fiber can can block some of the microwaves reaching The Crucible now in real life situation you probably won't notice much of a difference between using thinner or thicker Chambers for quick meltdowns but it could be noticeable if you make your Chambers extremely thick thinking that it's going to make your metal melting process faster in small crucibles that said you will need to make your Chambers thicker when melting higher melting point metals or using bigger or thicker crucibles it all depends what you melt the quantity and the size of The Crucible what you will see me doing quite often is preheating The Crucible with a blow torch I only do it for 30 seconds or a minute but it's enough to shave a few minutes of microwaving in some cases and how it's even possible that we can put metal in the microwave what about arcing arcing is actually not that common there is a reason why I folded the fork and put another sharp object beside it to increase the chances of arcing happening it doesn't mean that you should put metal in a microwave when cooking food what I'm saying is that arcing is not an issue especially when a metal is inside the crucible that absorbs large portion of the microwaves one of the reasons why I don't wear gloves on some occasions is to demonstrate how efficient is the chamber when you do these quick meltdowns the chamber doesn't have time to heat up from the outside unless you microwave for longer or The Crucible stays in the chamber for longer then sure it will get hot and you'll need glass that said please wear your gloves at all times this is only for demonstration purposes I know the space of improvement in my personal safety equipment I'm not the perfect example stay safe and happy metal melting

Channel: Shake the Future

Views: 562,100

Keywords: microwave metal melting, melt metals in microwave, microwave furnace, microwave foundry, metal melting, metal casting, meltdown, crucible making, silicon carbide, inside of the microwave

Id: P1VmIYheuU4

Length: 35min 29sec (2129 seconds)

Published: Fri Apr 14 2023