in modern processes, they use Rapid Thermal Processing to save thermal budget because any time spent heated causes more dopant diffusion and the dopant can diffuse into places you don't want with excessive annealing. The RTP ovens are really cool, they use halogen bulbs to flash heat the wafer to >1000C in under a second for a few seconds, basically the Easy Bake Oven from Hell.
That is super cool! I have heard of this process before because an RTP oven is needed for annealing after ion implantation. i hadn't considered making one though because i thought it would be too hard to source parts. Do you think that an RTP oven is something that I could build myself?
There doesn't seem to be much you've posted, but if you keep posting videos of this quality this is likely to become one of my favorite UA-cam channels.
listen to this guy. We need more creaters like you to balance out the crap. I never plan to make wafers in my workshop but I really enjoyed and watched this whole video.
@@projectsinflight Niche topic? It's not niche at all, it's just a lot less noisy than "hot" topics, where people tear at each other. Science seems to be too difficult and expensive for somebody who has no access to a lab and you show how it can be done on a tight budget.
I work in semiconductor manufacturing, and you can often tell if a wafer was located at the end of the tube or at the centre - plotting the electrical characteristics the devices being manufactured will show this. Even a few degrees can make a large difference, enough to cause issues with the end product, so temperature control is very important for consistency.
yeah, i am actually not super impressed with the consistency of the temperature in the middle of the furnace and i might increase the tube size and heating element width when i replace the tube
@@projectsinflight It might be more consistent once it is sealed. Where I work, the equipment is old, so we have to live with it, and the particular devices we manufacture have wide tolerances. I've never gone into the physics of it, but I guess that the diffusion of dopants into silicon becomes exponential near +1100'C?
The heat loss will be mostly near the ends of the tube, so if you want consistent temperature along the tube, instead of minimal electricity use, winding the element all the way to the end of the tube would make sense. You could even do the opposite of the current situation: instead of having no windings near the end of the tube, have them spaced closer together near the ends. What is your current on/off cycle for your solid-state relay when heating the tube? if you don't need short rise time, you could add the variac to reduce voltage and have shorter on/off cycles of the solid-state realy, which may help stability of the temperature. The other option is to go with refractory brick, which has more mass than the current insulation material, resulting in more stable temperatures.
In the furnaces that I worked on (BTU, ASM), we defined a "flat zone" within the tube where temperature control was even tighter. We ran 3 profile thermocouples of different lengths (there were spike TC's on the outside to rough in the temperature towards setpoint), in from the ends of the tube with the measurement bead at three different points. These looked similar to the TC used in the manufacturing of this furnace.The output from these was used to characterize and fine tune the furnace temperature.
I'ts not everyday that I see a single video form a channel and immediately subscribe. This was really well done, and I am excited to see you make your own transitors.
Exactly what Jo said. I want to help but I don’t make much money(I don’t care to), but I do have a supply of Quartz tube in the western Appalachian mountains area. What are your ID/OD/Length needs? If I have it in inventory, it’s yours for the cost of shipping.
An old foundry tip for your enclosure: make an outer shell that stands about 1cm away from the main shell, and is made from perforated sheet metal. Aluminum sheet would be a good choice. The perforations allow airflow, and the heat from the main shell will create convection. The outer shell will stay safely cool because it has a continuous flow of room temperature air moving past it. Foundries used that trick for their furnace doors.
I’ve seen one or two people messing with silicon chips but they had old equipment that was probably way out of reach. Awesome to see someone sharing how to make it more approachable. Thank you greatly for making this. I can’t wait to see more
professional kilns use ceramic insulators as wire guides for passing through the metal skin, there a heap more robust then a single layer of heatshrink. probably worth looking into. also take note of the temp range of nichrome wire, there usually recommended 900c, Kanthal is also a good choice (about 1400c). Shy of that, looks like a pretty good build. good work.
Kanthal A1 is indeed superior to NiCr wire. The only downside is that Kanthal is incompatible with sodium in the sodium silicate in the refractory cement. Perhaps a different kind of cement? I noticed in the pictures he showed of commercial tube furnaces that they held the Kanthal wire in rigidized ceramic fiber forms.
This is one of the very best presentations of a technical process anywhere on UA-cam. Thank you for an excellent explanation of a great project. Also, your narration is so much superior to just about all the others there. Bravo and good luck with your furnace!
Its not often you get see such amazing content on this god forsaken platform. Thanks for sharing your fascinating the journey outside of the reach of all but a special few in the industry typically. Best of luck in all your future works.
Brilliant video, really great to see scientific furnaces being built, and your presentation style is very engaging. Was very surprised to see the element being wound on the tube, my experience is mainly with boxes being built around the tube and then surrounding the tube in elements. Amazing to see it work, especially at 1200! If your winding elements and want repeatable results, you might consider building a coil/transformer winder. There's 3D printable designs that you could extend for your tubes. I think you said at one point refractory brick was too expensive to use in construction, but my experience is that it's very cheap. The main reason i would build it with refactory is to have easily replaceable elements and tubes. I tend to break alumina tubes with the reactions we do (cement clinkers). My experience is that the ramp rate limits on ovens are to protect the life of the elements rather than the tubes, or to handle localised temperature differences causing thermal stress if the furnace is heavily loaded (not the case here). Quartz tubes can normally take a real beating. There is also some guidance around the initial first use bake out too where moisture is driven off, but you seem to be on top of that. I really want to build a drop calorimeter, and your video/work has given me loads of confidence to try building my own oven, so thank you! Looking forward to the next video.
Oh yeah 100% the correct way to build this is with the element embedded in the brick and not wound on the tube. I made it this way because it was a lot easier (at least it seemed like it was at the time). Feel free to use any of my code when you build your oven! I've been working hard to make sure it works well.
Sweet! I'll be looking forward to the atmosphere isolation modification! What kind of photolithography setup will you be thinking of getting/making? Finding a pre-built old lens system? Or use a projector like Sam Zeloof did? I'll set off on the mega-project of making IC-s after I have designed and built my e-bike motor, so probably in about a year.
I'm going to start by using photolithograpy materials for PCBs (photofilm resist + laser printer + transparency film) and then move on to spin-coating with liquid resist. It's surprisingly difficult to find photoresist for semiconductor devices online, so I'll see what I can scrounge up.
@@projectsinflight The channel @BreakingTaps has done some similar work in the past, if you haven't already seen them it might be worth looking him up.
Wow... I am stunned on multiple levels. This was a great video! I really hope, you will be able keep exploring this path, and more importantly, take us along with it. Making something like a chip myself would be absolutely awesome. Never would i have thaught it to be possible, and yet, i stumble into such a video where someone claimed exactly that. I immediately subscribed, and i am very much looking forward to your next video
I'm pretty confident that I will eventually be able to make a very simple IC (where IC = greater than one device on the same chip). I'm currently working my way through the 4 main fabrication processes to get there: 1. oxidation 2. lithography 3. diffusion 4. metalization Once I have all of these working, I should be able to make an IC
K thermocouples rated for 1000C are actually supposed to last a certain amount of firings before the element degrades and the readings become affected, thicker elements last longer but have a slower response and vice versa. There are some thermocouples rated for many more cycles, the S thermocouples, but are very expensive compared to the K thermocouples because they are made of platinum alloys.
This is good to know. I think that lindberg tube furnaces use type R thermocouples and not type K either. It's possible then I should try one of the non-K type thermocouples for this project
@@projectsinflight In general do not trust cheap chinise thermocuples readings, you must make sure that the temperature-voltage curve is mantained over all the whole temperature range. Thermocuples that report too low can melt down your heating element. Going to temperatures above the recomended for a certain thermocuple can also change the curve in unexpected ways, In general K thermocuples should last a long time if you don't go above 700C, at 1200C they can wear them down really fast!
Thank you so much for your encouragement. It really means a lot to me as a first-time uploader. I've been really happy how all of the comments are so constructive.
This is a great video, Quartz normally can withstand much greater temperature ramps / gradients than 30 C (for instance you heated it with the ends exposed in air lol). More likely it broke due to the difference in thermal expansion between the quartz and the refractory cement coating or some issue with the coil itself caused a hot spot. I was in a lab where we had to re-wire muffle and multi-zone tube furnaces every few months, most the tubes were corundum with some being quartz, you can re-use the tubes in most cases when the elements fails if it's not coated. Coating vs not coating usually has little impact on real world difference.
nice project, remember that you need to use heat sink for SSR otherwise it could get faulty and doesn't disconnect the element anymore!! it happened to me me before
I tested the temperature of the SSR over many runs and it never seemed to get very warm so I didn't bother with a heat sink. It's possible I'm just not running enough current through it for it to warm up. It's rated for 80A and I'm doing 8A.
@@projectsinflight Sounds like you must be using a legit brand SSR, though I don't immediately recognize the brand. For anyone reading this, though, DO NOT believe the ratings of cheap Chinese SSRs, especially the omnipresent "Fostek" brand. I had one blow on me so I disassembled it and found the MOSFET inside was terribly underrated for the claimed Amp rating on the SSR. I swapped the blown FET with a better one from my parts bin and it's still churning on my homemade 3D printer's oversized (300mm x 600mm) heated bed.
I usually use a SSR with 2 or 3 time higher amper than I need , because there is alot of cheap and fake brands in market, I put a contactor or Miniature fuse in case of faulty SSR@@SansNeural
Cool video! (lol). This reminds me of Corning and how they made fiber optics. They had a furnace several hundred feet tall, where they poured molten glass into the (hot) air to create fiber optics. Only way to end up with miles of optical fiber glass of consistent diameter.
FYI, kapton tape is really useful to have on hand for any time you need tape that handles high temperature and liquids. It's also a good insulator, so really usefull all round
I once used this type of solid state relay. In total I used 24 pieces of it. Sadly two of them failed after a few hours. They failed CLOSED. So maybe you want to add a secondary cutoff. Something like a thermal fuse in the housing or an independent contactor or something. Especially since the Arduino can crash due to a random bit flip by radiation or due to a brown out. I wouldn't be able to sleep well having this in my house. Feels much better to engineer it right with some fault tolerance.
Please get some glasfiber sleve for your internal cables! You can get them real cheap from china like 1,50$/m Also crimping the copper wire to the Nichrome wire would be good to do.
@@projectsinflight Don't have any off-hand but I know you should pay no more than $40 for a good one and no less than $20 to avoid the bad ones. The best ones are produced in Sweden and Germany (yes I am biased) :)
Great video. For high temperature passthrough you can use ceramic fuses. Just take them apart and you have ceramic tube you can glue in with refractory cement to have certainty that wires won't short to metal body
There are heat resistant insulation sleeves for wires, often found in halogen lamps and electric toasters. Instead of only twisting the wires together, you could use just the metal bit from the common plastic screw terminals. I have used these to re-connect heating elements in ovens and they seem to stand up to high temperature quite well.
@@klausnielsen1537 Yessir I will. But I later realized that @zyeborm was probably talking about the Lithium battery powered spot welders while mine is a "cheap" benchtop model. Mine doesn't seem to weld any better than the really cheap ones, though ;)
Nice work. I started going down this road a while back. Wanted a bigger "aperture" at around 2" so I attempted to slip cast a ceramic tube. Made a 2ft tall 5part mold out of plaster of paris and poured the slip into that. Wait a bit for desired wall thickness and then pour off the remainder. Didn't come out too bad, but the biggest issue was that the inside of the tube was quite lumpy rather than smooth. I don't think I spent enough time mixing the slip, though I felt I had mixed the crap out of it. I never followed up with another attempt.
@@projectsinflight Yeah i think the problem was I having trouble finding a 2" quartz tube that was 2ft long. I mean I'm sure they make them, but I couldn't find anything I could just click and order. I didn't look all that hard though to be honest. One day ill pick back up on this.
13:18 I highly recommend to replace those heat shrink tubing to some glass fabric insulation (you can buy them or get one from old appliances like electric kettles). There is also thing called pyrojacket sleeves. It may be an interesting alternative for tube insulation (some companies claim they withstand 1650C).
For controlling your furnace you can add a bluetooth, wifi, real time clock, sd module for data logging and many more, you have the hardware to make way better then the normal furnace controllers. Controlling power with PWM is also a thing.
Oh! I do have the SD module and RTC already, but bluetooth/wifi might be nice actually. I live in fear of leaving this thing on and going to sleep lol!
I worked in a semiconductor fab back in 1972, making microwave varactor diodes, giant SCRs and diodes for diesel-electric locomotives, and some planar epitaxial transistors for the low GHz range. We had a load of tube furnaces, it was back in the days where we grew our own silicon boules pulled from a melt. We were only using 2 inch diameter wafers in '72, although the transition to 4 inch was being planned by '73. We were pumping silane gas, plus a load of toxic dopants, and using scary etchants with HF. It felt a lot like home-shop bucket chemistry. Those big SCRs were bonded to 4" x 4" x 0.75" copper bases. We had a room-sized capacitor bank for testing the power diodes and SCRs. It all felt like working in that infamous HP garage, although it was a huge factory. I only worked there during the summer vacations, as I was still at high school, aged 15 when I started. It was huge fun and really opened my eyes to the possibility of a career in science-based tech.
This is a cool project. Reminds me that I need to finish my smd solder oven project... Definitely good to see more people trying to DIY IC development. It's an unfortunately top heavy industry that has no need to be that way. Best of luck!
Integrating the heating element and the quartz together is a bad idea: - In case of failure both become waste, because they are bonded together. - Quartz is amorphous, but it can recrystallize at high temperatures if you contaminate it with the refractory cement. And you dont want crystalline quartz, it can fail easily. - Cause difficulties to clean the quartz tube. - Quartz is a fantastic material. You can heat up to white glowing and then you can immerse in water, and won't crack. This means it can withstand higher heating and cooling rates than 30C/min. If your design is limited to 30C/min (beacuse of thermal stress) than it is another reason no to bond the quartz and the heating element together.
The 30C/m figure was from a couple of manuals for tube furnaces that I looked up while researching this project. I just kind of took it on faith, and it seemed reasonable at the time so I went with it. I am starting to wonder if maybe it was listed for a different reason than to protect the tube... At any rate, regarding the bonding of the heating element to the tube, I do agree that it's a suboptimal choice, and it would be better to have the tube separate. The reason I chose to make it like this was because this was the easiest and cheapest method. The other option would be to embed the heating element into refractory brick material. Alumina wool is substantially cheaper than an equivalent volume of refractory brick material, and winding the heating element around the tube is easier than embedding it into refractory bricks. That being said, I am considering making another tube furnace exactly like that.
I have this fabrication method in mind. Wrap the glass in two layers of paper. Then a very thin layer of wool that you now wind your coils on. Apply a very very light coat of sodium silicate . Followed by another thin layer of wool and apply one more light coat of sodium silicate. And role another layer of paper over all the wool. Then when you gently warm it up a few hundred degrees (outside of cource) the paper burns away and the co2 reacts with the sodium silicate and bonds the wool fibers around the coil. You can burn off the all the paper and carbon letting oxygen remove it. Now After letting it cool down, if all went well, you should be able to replace the quartz tube, and the wool coil should retain its shape while cold and I hope retain its shape around tube when reheated to its working temperature. Key is to not use too much sodium silicate.
My best guess for the earlier tube cracking is that your insulation is severly lacking. 150°C on the outside of your furnace is a clear indicator. While not an extreme hazard it's kinda not good for a uniform temperature to leak heat everywhere. This lack in insulation also leads to your heating elements to cool faster than the tube, which consequently gets crushed. Not sure about the price of alumina wool in your area, but maybe look into rockwool for insulating your house. You can't go cheaper than this and we use it in our lab to build tube-furnaces for about 600-800°C (smells kinda funky the first time you heat it up though). Not sure about 1000+°C (aka directly on the elements), but definitly consider it for outer layers. About the heating rate, the manual for our "real" high temperature(1600°C) tube furnace recommends 400/Tube ID(mm) K/min. It's for a ceramic tube though, which is a bit more sensitive than quartz. Just keep in mind that for a bigger tube you should maybe decrease the heating rate. At any rate this is good content and i'm exited for your future developments. @@projectsinflight
@@projectsinflight Assuming the OP is correct, I suggest sleeving the entire (heater) length of nichrome wire in fiberglass tubing to prevent inter-winding shorts. Then to make it hang onto the quartz tube in the absence of any adhesive, first wind the correct number of turns on a smaller diameter forming rod so the heating coil will grasp the quartz tube after being threaded onto it. It's quite possible the nichrome coils will relax some after heating, but it should still be more snug than if formed directly on the full diameter tube.
I don't think sleeving the elements for these temperatures is appropriate, most of the heat transfer is radiant at these temperatures so this would massively increase the wire temperature.
just found your channel! amazing work on your tube furnace :D i really really hope you keep up your work and we will see some homemade semiconductors here on YT.
Hi I've built a few 1000 C furnaces, I used nichrome wire for the heating element. that did not last long the last one only worked for 3 firings before the element gave up, I should have used Kiln high temp treated nichrome. I like the idea of using a quartz tube for the shell, It could be evacuated to help for heat treating steel then I would not need to wrap in stainless foil Rich
Woah- can you give me any info on the high-temp version of nichrome? This seems like something I should be aware of since i am going to make a new coil/tube assembly soon.
hi this is what I found, Kanthal® A-1 is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1400°C (2550°F). The alloy is characterized by high resistivity and very good oxidation resistance.@@projectsinflight
Right, well you're definitely getting a sub for that. I had not come across a tube furnace, nor had I realised that homemade semiconductors could be a thing. Great video, thank you.
When I went to go hit like, I saw 555 had already liked it, as if to foreshadow, one day, you'll make your very own 555 timer chip. Thanks for this video. 😊
Just found your channel and man, you are an inspiration. You're doing it all, craftmanship, science and coding. But more importantly, you are brining life to your thoughts and your curiosity. Subbed and can't wait for more videos. PS, saw you newest video as well which was absolutely incredible!
When assembling sheet metal like this, you should use pop rivets. These will draw the metal tightly together and allow for some movement between the two pieces if needed without losing the strength of the joint. Also, when attaching nichrome wire to copper wire, be sure to tin the copper wire if your copper is not already silver or tin covered. Then, use a compression sleeve to bind the two wires together. This ensures a safe and reliable connection. I too am building a tube furnace, but I', using induction rather than resistance for heating as my target materials and temperatures are different. I'm going to much higher temperatures for metallurgical testing. Your video has convinced me that I should record my journey and maybe post videos on it. It does have some magic sauce in the furnace for R&D purposes, so I'll need to be careful not to release that information before my provisional patents come through. I do have one issue that I've been unable to find a solution. Measuring the temper within such a strong magnetic field has been problematic. Everything I've tested has been destroyed or damaged. Any ideas what can be used to measure inside an opaque ceramic vessel that can handle a magnetic field of 4 to 8 tesla? Typical thermocouples have just been melting, even the bead types. I'm yet to find a thermistor that can take such a high temperature.
Good idea on the compression sleeve- i made a note to look into it. Regarding your furnace, if you are using induction what do you need the tube for? Sorry- I don't have any idea about your temp measurement problem. If you cannot use an electrical means to measure temperature all I can come up with is to measure the wavelength of the blackbody radiation somehow...
@@projectsinflight I'm working on a metallurgical study involving next generation magnets. These types of furnaces are typically hydrogen fired, but for my process, the induction heating is vital. The temperature control needs to be within a 5 degree tolerance. Outside of this window, and the very special properties I'm investigating and manipulating diminish quickly.
The thermocouple was rated for 1000°C but in vacuum. In air the stainless steel oxydize and do that (I'm not sure but I think the black oxyde is chromium oxyde)
Possibly! I was looking around and I didn't really see any other thermocouples rated for 1000C that had that metal shielding- most were the ceramic shielded ones. I'm about 50-50 right now on your explanation vs bad amazon listing.
@@projectsinflight I use a thermocouple with stainless steel shield at 1300°C at work in a vacuum kiln it works 100%. But I've tried once to put a bloc of stainless in a kiln at 1000°C in air, the result was exactly the same! But ceramic is the only solution if you aren't using argon or other neutral gas
You are excellent. Your channel is a piece of art, your filmmaking skills are stellar, your narration is captivating. I can't get enough of your content. Never quit!
Id say look into exhaust paint rather than engine paint. It has a lot higher temp rating and works pretty well. That said cant say for sure if it doesnt act the same as barbecue paint since ive only used it on heatshields
so far people are suggesting brake caliper paint which seems appropriate. I've got to look into the pros and cons of each type of paint. Who knew every component of a car has it's own special paint lol
So happy to found another channel like Applied Science and The Thought Emporium, instant subscribed after this video. Can't wait to see your future projects.
I dont usually subscribe to a channel with so few videos. This popped up in my algorithm and it was so well done and interesting i could not help myself. Please fo not let the UA-cam "why dont you... i could do it..." want a be's grind away at you. If you had a Super Thanks i eould have immediately sent you some $$$. I will look at your Patreon if the content stays this good snd the narrative so quasi professional. Thank you and i hope you post a lot more. You give off the learning/experimenting glow I used to have when i was young! : }
I've been watching your videos and it's bingable for me. I always dreamed of doing this but unfortunately I'm disabled and have very little money, so now i get to live vicariously through you
For the wire connections you'd probably want high temperature crimp connectors and silicone coated fiberglass sleeving for electrical insulation on your passthroughs.
Commercial ovens use alumina tubes and ferrules and woven fiber glass tubes as wire insulators. Also, thermocouple can have alunina insulator around it.
Wow, this is perhaps the most thought provoking video I've seen in several years. I smashed the subscribe button so hard i was concerned that i had broke my phone. Thank you so much for this video, will save me a fist full of cash
If you want to do this really cheaply i'd actually recommend looking for a used tube furnace that is really old and junky. You can often find incomplete furnaces with just the heating element, thermocouple, and insulation for less than $100. add the controller yourself and you're done.
Looking forward to more content from your channel! Your video was very interesting and I even learned a few things I hope you post more soon thank you for your time and trouble!
Sheet metal screws fasten from one side; they're the middle ground between pop rivets ($) and solid rivets which need access to both sides. Also there are ceramic scissors (ostensibly for Kevlar jacketing on optical fiber) that might be better for that insulation.
Dude, I hope you're not just yanking my chain. This is really great stuff. Since Sam Zeloof completely gave up on making videos in favor of running his own fab, we need another hero to take his crown. Homebrew semiconductors needs to become a thing.
Great project and many good tips! Found Your channel by chance and subscribed, much of what You do resonates with me.... Some minor tips that may be useful if You have not seen them: I have made some heaters with nichrome wire and a good reliable way to to terminate the wire is is to twist it back on itself and terminate on a copper block with a screw through the loop (or a copper ferrule). Twisting keeps the connection cooler. Perhaps khanthal wire would be better if You need over 1000C, but then You can not use that silicate cement. Use porcelain and fiberglass insulators. I salvaged fiberglass wire from our old cooking stove. I also believe quartz will have limited lifespan above 1000C, maybe a slightly more expensive alumina tube would be better. They seem to be available fairly low cost nowadays. Have no idea about out gassing etc though for Al2O3.
this is extremely interesting. this is exactly the same concept behind rebuildable DIY vaporizer works. I got into vaping around ten years ago and was able to quit smoking. and I've learned how to wind my own coils and whatnot, basically this is exactly the same principle behind how that works
Haven't exercised the neurons that learned (the rudaments of) this at undergrad in about 20 years - thank you! Also, incredibly happy to see that one can push semiconductor manufacturing into the bounds of DIY. To be less serious- def tabbing this Primitive Technology video to prep for the coming zombie apocalypse 😂
For the wire wrapping you could use a spacer of another wire, or a thin strip to ensure an even distribution that won't shift as you apply the compound over it.
This is a great video. I was just browsing online for used tube furnaces and came to the same conclusion as you did, far too expensive! My next thought was to DIY, I'll be using your video as a guide to create my own tube furnace. Well done. Thanks for the video! P s. Ive seen thermocouples do that at high temp. Anything above 750c will cause them to act funky.
7:22 it's not Conducting heat instead the Heat is Leaking in IR form so may be you should use any reflector between tube and insulation or place reflector like Steel foil between insulator so it will be safe from heat and prevent ir leaking.
@@projectsinflight for years I believed that it had to be possible to make my own hi temp kilns but I couldn't wrap my mind around how to do it. Thank you for putting this video up so I can see it done and in a really interesting way. Do you think borosilicate glasses would fuse to the quartz glass? I'm picturing a 3" diameter set up like you made in this video . I would be putting class smoking pipes in it to aneal in between working processes
Instant sub earned. I would try to replace the massive stainless steel rod with a thermal capacity of a bazzillion with something less thermal shock inducing. Like a burnt out core of a very long carpenter's pencil or something, to stay in the DIY realm, although you should not burn it inside your tube, as metal vapor would probably contaminate your tube forever.
I wonder if you put a stainless steel jacket over the outside of your tube if it'd help with temperature evenness and getting a bit of thermal mass to help with stability. It'd essentially be a consumable though I don't think it'd be too happy up there. You might consider a triac type arrangement rather than the SSR as well. You won't have much thermal mass in the wire so I think you'll be getting much larger temperature swings than what you're measuring especially with the amount of thermal transfer that'll be done by radiation rather than by other means. Aliasing from that effect might be something you're seeing with your stability. There are arduino triac boards and code that are meant to just plug in but I haven't used them yet. Great video mate, really keen to see how you progress with this.
@@projectsinflight You could take the insulation out, insulate the Copper cables with fibreglass sleeve or ceramic tubes and then use the tube furnace to bake the paint in place. Do it outdoors though, might need to insulate the box from the outside with some rockwool and longer cables to your controller.
@@projectsinflight semi conductor world is linked to glassblowing. A cheap mini torch and hydrogen/O2 can easily work quartz. Propane/O2 can but is still dirty (for making boats and sputter material boats. When working quartz, the quartz will out gas SiO2 that condenses as "cob webs" be advised for fumes. I've fancied working colored borosilicate glass to out gas heavy metals from the stoichiometricaly denser colors. Colored glass is chemically inert, vs storing pure toxic metals I may need micro grams of (it's artsy fartsy chemistry, batches and mixtures are not pure or may be guarded trade secrets.)
it didn't really come across on video but just the friction alone was enough to keep it thoroughly immobilized. it shouldn't be in any danger of sliding out as-is (famous last words lol)
![Lp. Сердце Вселенной #60 РОЖДЕНИЕ ЛОЛОЛОШКИ [Финал] • Майнкрафт](http://i.ytimg.com/vi/YoR0pAV9FVQ/mqdefault.jpg)
I'm really glad the algorithm brought me to your channel. Excellent work!
Ben! It means a lot to hear this from you. Your channel has been a huge inspiration of mine!
in modern processes, they use Rapid Thermal Processing to save thermal budget because any time spent heated causes more dopant diffusion and the dopant can diffuse into places you don't want with excessive annealing. The RTP ovens are really cool, they use halogen bulbs to flash heat the wafer to >1000C in under a second for a few seconds, basically the Easy Bake Oven from Hell.
That is super cool! I have heard of this process before because an RTP oven is needed for annealing after ion implantation. i hadn't considered making one though because i thought it would be too hard to source parts. Do you think that an RTP oven is something that I could build myself?
"easy bake oven from hell" is my new favorite phrase
It is just a oven with IR lamps. Lamps should be available as spare parts.
They make pizza ovens that do the same thing just not as hot. 😅
Wouldn’t you have to pull a vacuum for radiant heat to heat a surface that quickly?
There doesn't seem to be much you've posted, but if you keep posting videos of this quality this is likely to become one of my favorite UA-cam channels.
thank you for your encouragement. it really means a lot that people are interested in such a niche topic :)
I totally second that. Subbed because hope is good!
listen to this guy. We need more creaters like you to balance out the crap. I never plan to make wafers in my workshop but I really enjoyed and watched this whole video.
@@projectsinflight Can you do a video, in-depth on building your own integrated circuits. Would like to see more so I can do it myself.
@@projectsinflight Niche topic? It's not niche at all, it's just a lot less noisy than "hot" topics, where people tear at each other. Science seems to be too difficult and expensive for somebody who has no access to a lab and you show how it can be done on a tight budget.
The temperature probe visibly disintegrating was quite awesome!
Yeah I was flabbergasted when I saw that and immediately whipped out the camera because I figured If I didn't have proof no one would believe me
@@projectsinflight it looks to have oxidized to shit. You sure it wasn't rated only for intert atm/vacuum?
I work in semiconductor manufacturing, and you can often tell if a wafer was located at the end of the tube or at the centre - plotting the electrical characteristics the devices being manufactured will show this. Even a few degrees can make a large difference, enough to cause issues with the end product, so temperature control is very important for consistency.
yeah, i am actually not super impressed with the consistency of the temperature in the middle of the furnace and i might increase the tube size and heating element width when i replace the tube
@@projectsinflight It might be more consistent once it is sealed. Where I work, the equipment is old, so we have to live with it, and the particular devices we manufacture have wide tolerances.
I've never gone into the physics of it, but I guess that the diffusion of dopants into silicon becomes exponential near +1100'C?
The heat loss will be mostly near the ends of the tube, so if you want consistent temperature along the tube, instead of minimal electricity use, winding the element all the way to the end of the tube would make sense. You could even do the opposite of the current situation: instead of having no windings near the end of the tube, have them spaced closer together near the ends. What is your current on/off cycle for your solid-state relay when heating the tube? if you don't need short rise time, you could add the variac to reduce voltage and have shorter on/off cycles of the solid-state realy, which may help stability of the temperature. The other option is to go with refractory brick, which has more mass than the current insulation material, resulting in more stable temperatures.
In the furnaces that I worked on (BTU, ASM), we defined a "flat zone" within the tube where temperature control was even tighter. We ran 3 profile thermocouples of different lengths (there were spike TC's on the outside to rough in the temperature towards setpoint), in from the ends of the tube with the measurement bead at three different points. These looked similar to the TC used in the manufacturing of this furnace.The output from these was used to characterize and fine tune the furnace temperature.
I'ts not everyday that I see a single video form a channel and immediately subscribe. This was really well done, and I am excited to see you make your own transitors.
Thank you! It means a lot to me that people are encouraging.
Me too. Great video.
Exactly what Jo said.
I want to help but I don’t make much money(I don’t care to), but I do have a supply of Quartz tube in the western Appalachian mountains area. What are your ID/OD/Length needs? If I have it in inventory, it’s yours for the cost of shipping.
Hello, my name is Werner. I built my cylindrical furnace after showing your work, thanks a lot for all your videos.
i'd love to see it! my email is projectsinflight at gmail dot com if you want to show it off :)
An old foundry tip for your enclosure: make an outer shell that stands about 1cm away from the main shell, and is made from perforated sheet metal. Aluminum sheet would be a good choice. The perforations allow airflow, and the heat from the main shell will create convection. The outer shell will stay safely cool because it has a continuous flow of room temperature air moving past it. Foundries used that trick for their furnace doors.
I’ve seen one or two people messing with silicon chips but they had old equipment that was probably way out of reach. Awesome to see someone sharing how to make it more approachable. Thank you greatly for making this. I can’t wait to see more
Doing my best to do this without tons of expensive gear. Metallization is gonna be tough though. I may have to use a high vacuum chamber
ua-cam.com/users/shorts2-x3fDsOQG8
Brake caliper paint! It's good up to just shy of 1000 °C, but only needs about 90 °C to cure.
Oooh! This is a good idea I'll have to check it out
Not your garage but as a proud once-member of the HP Tech Support community I do appreciate the quiet shout-out :D
I was wondering if anyone would get the joke :)
professional kilns use ceramic insulators as wire guides for passing through the metal skin, there a heap more robust then a single layer of heatshrink. probably worth looking into. also take note of the temp range of nichrome wire, there usually recommended 900c, Kanthal is also a good choice (about 1400c). Shy of that, looks like a pretty good build. good work.
Kanthal A1 is indeed superior to NiCr wire. The only downside is that Kanthal is incompatible with sodium in the sodium silicate in the refractory cement. Perhaps a different kind of cement? I noticed in the pictures he showed of commercial tube furnaces that they held the Kanthal wire in rigidized ceramic fiber forms.
In 1 i was thinking you have over 100k subs becouse of the video quality but you have 1k of subs. Dude you deserve MORE than 1k of subs
Here's hoping :)
I hope you will get 100k soon
@@stavbycz686630.2k so far.
This is one of the very best presentations of a technical process anywhere on UA-cam. Thank you for an excellent explanation of a great project. Also, your narration is so much superior to just about all the others there. Bravo and good luck with your furnace!
Really Well Done! I’m excited to see what all you can do. Open Source Tube Furnace is awesome enough in of itself.
Its not often you get see such amazing content on this god forsaken platform. Thanks for sharing your fascinating the journey outside of the reach of all but a special few in the industry typically. Best of luck in all your future works.
Thanks I'm super excited to do more!
@@projectsinflight put your paypal link in a video
Brilliant video, really great to see scientific furnaces being built, and your presentation style is very engaging.
Was very surprised to see the element being wound on the tube, my experience is mainly with boxes being built around the tube and then surrounding the tube in elements. Amazing to see it work, especially at 1200!
If your winding elements and want repeatable results, you might consider building a coil/transformer winder. There's 3D printable designs that you could extend for your tubes.
I think you said at one point refractory brick was too expensive to use in construction, but my experience is that it's very cheap. The main reason i would build it with refactory is to have easily replaceable elements and tubes. I tend to break alumina tubes with the reactions we do (cement clinkers).
My experience is that the ramp rate limits on ovens are to protect the life of the elements rather than the tubes, or to handle localised temperature differences causing thermal stress if the furnace is heavily loaded (not the case here). Quartz tubes can normally take a real beating. There is also some guidance around the initial first use bake out too where moisture is driven off, but you seem to be on top of that.
I really want to build a drop calorimeter, and your video/work has given me loads of confidence to try building my own oven, so thank you! Looking forward to the next video.
Oh yeah 100% the correct way to build this is with the element embedded in the brick and not wound on the tube. I made it this way because it was a lot easier (at least it seemed like it was at the time). Feel free to use any of my code when you build your oven! I've been working hard to make sure it works well.
Sweet! I'll be looking forward to the atmosphere isolation modification! What kind of photolithography setup will you be thinking of getting/making? Finding a pre-built old lens system? Or use a projector like Sam Zeloof did? I'll set off on the mega-project of making IC-s after I have designed and built my e-bike motor, so probably in about a year.
I'm going to start by using photolithograpy materials for PCBs (photofilm resist + laser printer + transparency film) and then move on to spin-coating with liquid resist. It's surprisingly difficult to find photoresist for semiconductor devices online, so I'll see what I can scrounge up.
@@projectsinflight The channel @BreakingTaps has done some similar work in the past, if you haven't already seen them it might be worth looking him up.
Great job. Maybe wear anti cut gloves for pre-deburred work to prevent nasty cuts. They are fairly cheap and do work.
Yep! I have some now
Wow... I am stunned on multiple levels.
This was a great video!
I really hope, you will be able keep exploring this path, and more importantly, take us along with it.
Making something like a chip myself would be absolutely awesome. Never would i have thaught it to be possible, and yet, i stumble into such a video where someone claimed exactly that.
I immediately subscribed, and i am very much looking forward to your next video
I'm pretty confident that I will eventually be able to make a very simple IC (where IC = greater than one device on the same chip). I'm currently working my way through the 4 main fabrication processes to get there:
1. oxidation
2. lithography
3. diffusion
4. metalization
Once I have all of these working, I should be able to make an IC
@@projectsinflight Wire bonding will then become your next holy grail.
Great furnace and all the best wishes in your endeavour.
K thermocouples rated for 1000C are actually supposed to last a certain amount of firings before the element degrades and the readings become affected, thicker elements last longer but have a slower response and vice versa. There are some thermocouples rated for many more cycles, the S thermocouples, but are very expensive compared to the K thermocouples because they are made of platinum alloys.
This is good to know. I think that lindberg tube furnaces use type R thermocouples and not type K either. It's possible then I should try one of the non-K type thermocouples for this project
@@projectsinflight In general do not trust cheap chinise thermocuples readings, you must make sure that the temperature-voltage curve is mantained over all the whole temperature range. Thermocuples that report too low can melt down your heating element. Going to temperatures above the recomended for a certain thermocuple can also change the curve in unexpected ways, In general K thermocuples should last a long time if you don't go above 700C, at 1200C they can wear them down really fast!
That was super cool, presentation was very well put together
Well, this got my subscription. great quality! Thanks for the detailed explanations.
Thank you so much for your encouragement. It really means a lot to me as a first-time uploader. I've been really happy how all of the comments are so constructive.
This is a great video, Quartz normally can withstand much greater temperature ramps / gradients than 30 C (for instance you heated it with the ends exposed in air lol). More likely it broke due to the difference in thermal expansion between the quartz and the refractory cement coating or some issue with the coil itself caused a hot spot. I was in a lab where we had to re-wire muffle and multi-zone tube furnaces every few months, most the tubes were corundum with some being quartz, you can re-use the tubes in most cases when the elements fails if it's not coated. Coating vs not coating usually has little impact on real world difference.
You should double or triple up and twist the ends of your nichrome wire to make sure your leads stay cool.
nice project, remember that you need to use heat sink for SSR otherwise it could get faulty and doesn't disconnect the element anymore!! it happened to me me before
I tested the temperature of the SSR over many runs and it never seemed to get very warm so I didn't bother with a heat sink. It's possible I'm just not running enough current through it for it to warm up. It's rated for 80A and I'm doing 8A.
@@projectsinflight Sounds like you must be using a legit brand SSR, though I don't immediately recognize the brand. For anyone reading this, though, DO NOT believe the ratings of cheap Chinese SSRs, especially the omnipresent "Fostek" brand. I had one blow on me so I disassembled it and found the MOSFET inside was terribly underrated for the claimed Amp rating on the SSR. I swapped the blown FET with a better one from my parts bin and it's still churning on my homemade 3D printer's oversized (300mm x 600mm) heated bed.
I usually use a SSR with 2 or 3 time higher amper than I need , because there is alot of cheap and fake brands in market, I put a contactor or Miniature fuse in case of faulty SSR@@SansNeural
Cool video! (lol). This reminds me of Corning and how they made fiber optics. They had a furnace several hundred feet tall, where they poured molten glass into the (hot) air to create fiber optics. Only way to end up with miles of optical fiber glass of consistent diameter.
I can only imagine trying to make a furnace that tall!
7:25 “Frying Pans, who knew right?!?”
I've gotten a surprising amount of use out of that cast-iron pan in my shop :P
Wow, really amazing work! Excited to see what you do next!
FYI, kapton tape is really useful to have on hand for any time you need tape that handles high temperature and liquids. It's also a good insulator, so really usefull all round
yeah it's 100% on my shopping list now
I once used this type of solid state relay. In total I used 24 pieces of it. Sadly two of them failed after a few hours. They failed CLOSED. So maybe you want to add a secondary cutoff. Something like a thermal fuse in the housing or an independent contactor or something. Especially since the Arduino can crash due to a random bit flip by radiation or due to a brown out. I wouldn't be able to sleep well having this in my house. Feels much better to engineer it right with some fault tolerance.
Don't worry, I've got a fuse in there too.
Please get some glasfiber sleve for your internal cables!
You can get them real cheap from china like 1,50$/m
Also crimping the copper wire to the Nichrome wire would be good to do.
oooh, now this is a much better idea! i'll definitely do this when i replace the tube (i've got a 2ft tube coming shortly)
You, my man, need a pop-rivet set!
If you have any good recommendations I'm all ears!
@@projectsinflight Don't have any off-hand but I know you should pay no more than $40 for a good one and no less than $20 to avoid the bad ones. The best ones are produced in Sweden and Germany (yes I am biased) :)
Great video. For high temperature passthrough you can use ceramic fuses. Just take them apart and you have ceramic tube you can glue in with refractory cement to have certainty that wires won't short to metal body
There are heat resistant insulation sleeves for wires, often found in halogen lamps and electric toasters. Instead of only twisting the wires together, you could use just the metal bit from the common plastic screw terminals. I have used these to re-connect heating elements in ovens and they seem to stand up to high temperature quite well.
I wonder of one of the cheap ebay battery tab spot welders would have enough herbs to bond to nichrome
@@zyeborm Ooh! I've got one of those and some nichrome wire. I shall try that (I assume you mean bonding copper wire to the nichrome?).
@@SansNeuralwill you report back? That would be a cool experiment!
@@klausnielsen1537 Yessir I will. But I later realized that @zyeborm was probably talking about the Lithium battery powered spot welders while mine is a "cheap" benchtop model. Mine doesn't seem to weld any better than the really cheap ones, though ;)
There are also inexpensive ceramic (porcelain) wire nuts available that work very well.
Great quality video, subscribed, and I will wait for more!
Thank you for your encouragement- it means a lot to me!
Nice work. I started going down this road a while back. Wanted a bigger "aperture" at around 2" so I attempted to slip cast a ceramic tube. Made a 2ft tall 5part mold out of plaster of paris and poured the slip into that. Wait a bit for desired wall thickness and then pour off the remainder. Didn't come out too bad, but the biggest issue was that the inside of the tube was quite lumpy rather than smooth. I don't think I spent enough time mixing the slip, though I felt I had mixed the crap out of it. I never followed up with another attempt.
There's always room for another try! That being said quartz tubes arent too expensive and might be easier.
@@projectsinflight Yeah i think the problem was I having trouble finding a 2" quartz tube that was 2ft long. I mean I'm sure they make them, but I couldn't find anything I could just click and order. I didn't look all that hard though to be honest.
One day ill pick back up on this.
Why do you only have two videos out. I need a consume a library of your work my dude.
I've got another in the works! i am very excited to release it hopefully in the next week or so
You could layer in some perlite or diatomaceous earth to increase the thickness of your ceramic wool wrap.
There is IR reflector too. You paint it on.
13:18 I highly recommend to replace those heat shrink tubing to some glass fabric insulation (you can buy them or get one from old appliances like electric kettles).
There is also thing called pyrojacket sleeves. It may be an interesting alternative for tube insulation (some companies claim they withstand 1650C).
Yeah glass fiber is the plan. I'm gonna add that soon. Never heard of pyrojacket sleeves though. do you have a link?
For controlling your furnace you can add a bluetooth, wifi, real time clock, sd module for data logging and many more, you have the hardware to make way better then the normal furnace controllers. Controlling power with PWM is also a thing.
Oh! I do have the SD module and RTC already, but bluetooth/wifi might be nice actually. I live in fear of leaving this thing on and going to sleep lol!
@@projectsinflightwould love to see a video about the controller design! Looks amazing
I worked in a semiconductor fab back in 1972, making microwave varactor diodes, giant SCRs and diodes for diesel-electric locomotives, and some planar epitaxial transistors for the low GHz range. We had a load of tube furnaces, it was back in the days where we grew our own silicon boules pulled from a melt. We were only using 2 inch diameter wafers in '72, although the transition to 4 inch was being planned by '73. We were pumping silane gas, plus a load of toxic dopants, and using scary etchants with HF. It felt a lot like home-shop bucket chemistry. Those big SCRs were bonded to 4" x 4" x 0.75" copper bases. We had a room-sized capacitor bank for testing the power diodes and SCRs. It all felt like working in that infamous HP garage, although it was a huge factory. I only worked there during the summer vacations, as I was still at high school, aged 15 when I started. It was huge fun and really opened my eyes to the possibility of a career in science-based tech.
I have recently been looking into how to build my own high-temp furnace, so thank you for reading my mind. genius way to gain a subscriber
This is a cool project. Reminds me that I need to finish my smd solder oven project... Definitely good to see more people trying to DIY IC development. It's an unfortunately top heavy industry that has no need to be that way. Best of luck!
Integrating the heating element and the quartz together is a bad idea:
- In case of failure both become waste, because they are bonded together.
- Quartz is amorphous, but it can recrystallize at high temperatures if you contaminate it with the refractory cement. And you dont want crystalline quartz, it can fail easily.
- Cause difficulties to clean the quartz tube.
- Quartz is a fantastic material. You can heat up to white glowing and then you can immerse in water, and won't crack. This means it can withstand higher heating and cooling rates than 30C/min. If your design is limited to 30C/min (beacuse of thermal stress) than it is another reason no to bond the quartz and the heating element together.
The 30C/m figure was from a couple of manuals for tube furnaces that I looked up while researching this project. I just kind of took it on faith, and it seemed reasonable at the time so I went with it. I am starting to wonder if maybe it was listed for a different reason than to protect the tube... At any rate, regarding the bonding of the heating element to the tube, I do agree that it's a suboptimal choice, and it would be better to have the tube separate. The reason I chose to make it like this was because this was the easiest and cheapest method. The other option would be to embed the heating element into refractory brick material. Alumina wool is substantially cheaper than an equivalent volume of refractory brick material, and winding the heating element around the tube is easier than embedding it into refractory bricks. That being said, I am considering making another tube furnace exactly like that.
I have this fabrication method in mind. Wrap the glass in two layers of paper. Then a very thin layer of wool that you now wind your coils on. Apply a very very light coat of sodium silicate . Followed by another thin layer of wool and apply one more light coat of sodium silicate. And role another layer of paper over all the wool.
Then when you gently warm it up a few hundred degrees (outside of cource) the paper burns away and the co2 reacts with the sodium silicate and bonds the wool fibers around the coil. You can burn off the all the paper and carbon letting oxygen remove it.
Now After letting it cool down, if all went well, you should be able to replace the quartz tube, and the wool coil should retain its shape while cold and I hope retain its shape around tube when reheated to its working temperature. Key is to not use too much sodium silicate.
My best guess for the earlier tube cracking is that your insulation is severly lacking. 150°C on the outside of your furnace is a clear indicator.
While not an extreme hazard it's kinda not good for a uniform temperature to leak heat everywhere.
This lack in insulation also leads to your heating elements to cool faster than the tube, which consequently gets crushed.
Not sure about the price of alumina wool in your area, but maybe look into rockwool for insulating your house. You can't go cheaper than this and we use it in our lab to build tube-furnaces for about 600-800°C (smells kinda funky the first time you heat it up though). Not sure about 1000+°C (aka directly on the elements), but definitly consider it for outer layers.
About the heating rate, the manual for our "real" high temperature(1600°C) tube furnace recommends 400/Tube ID(mm) K/min. It's for a ceramic tube though, which is a bit more sensitive than quartz. Just keep in mind that for a bigger tube you should maybe decrease the heating rate.
At any rate this is good content and i'm exited for your future developments.
@@projectsinflight
@@projectsinflight Assuming the OP is correct, I suggest sleeving the entire (heater) length of nichrome wire in fiberglass tubing to prevent inter-winding shorts. Then to make it hang onto the quartz tube in the absence of any adhesive, first wind the correct number of turns on a smaller diameter forming rod so the heating coil will grasp the quartz tube after being threaded onto it.
It's quite possible the nichrome coils will relax some after heating, but it should still be more snug than if formed directly on the full diameter tube.
I don't think sleeving the elements for these temperatures is appropriate, most of the heat transfer is radiant at these temperatures so this would massively increase the wire temperature.
just found your channel!
amazing work on your tube furnace :D
i really really hope you keep up your work and we will see some homemade semiconductors here on YT.
I'm sure trying! Hope to have a few videos for the 4 basic fabrication steps soon!
This was a really interesting and high quality video. I really enjoyed it even if I don't plan on building semiconductors in my garage😂👍.
I'm always happy to share and I think learning is valuable even if you don't intend to complete a project yourself!
Hi I've built a few 1000 C furnaces, I used nichrome wire for the heating element. that did not last long the last one only worked for 3 firings before the element gave up, I should have used Kiln high temp treated nichrome.
I like the idea of using a quartz tube for the shell, It could be evacuated to help for heat treating steel then I would not need to wrap in stainless foil
Rich
Woah- can you give me any info on the high-temp version of nichrome? This seems like something I should be aware of since i am going to make a new coil/tube assembly soon.
hi this is what I found, Kanthal® A-1 is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1400°C (2550°F). The alloy is characterized by high resistivity and very good oxidation resistance.@@projectsinflight
Right, well you're definitely getting a sub for that. I had not come across a tube furnace, nor had I realised that homemade semiconductors could be a thing. Great video, thank you.
Thanks! I'm glad you liked it
When I went to go hit like, I saw 555 had already liked it, as if to foreshadow, one day, you'll make your very own 555 timer chip.
Thanks for this video. 😊
Heh, I use a Firefox add-on that shows Dislikes, 9 and counting. Weird.
Super neat vid! I love seeing the science side of yt and you absolutely nailed it :D
Thank you! I try ;)
Just found your channel and man, you are an inspiration. You're doing it all, craftmanship, science and coding. But more importantly, you are brining life to your thoughts and your curiosity. Subbed and can't wait for more videos. PS, saw you newest video as well which was absolutely incredible!
When assembling sheet metal like this, you should use pop rivets. These will draw the metal tightly together and allow for some movement between the two pieces if needed without losing the strength of the joint. Also, when attaching nichrome wire to copper wire, be sure to tin the copper wire if your copper is not already silver or tin covered. Then, use a compression sleeve to bind the two wires together. This ensures a safe and reliable connection.
I too am building a tube furnace, but I', using induction rather than resistance for heating as my target materials and temperatures are different. I'm going to much higher temperatures for metallurgical testing. Your video has convinced me that I should record my journey and maybe post videos on it. It does have some magic sauce in the furnace for R&D purposes, so I'll need to be careful not to release that information before my provisional patents come through.
I do have one issue that I've been unable to find a solution. Measuring the temper within such a strong magnetic field has been problematic. Everything I've tested has been destroyed or damaged. Any ideas what can be used to measure inside an opaque ceramic vessel that can handle a magnetic field of 4 to 8 tesla? Typical thermocouples have just been melting, even the bead types. I'm yet to find a thermistor that can take such a high temperature.
Good idea on the compression sleeve- i made a note to look into it. Regarding your furnace, if you are using induction what do you need the tube for? Sorry- I don't have any idea about your temp measurement problem. If you cannot use an electrical means to measure temperature all I can come up with is to measure the wavelength of the blackbody radiation somehow...
@@projectsinflight I'm working on a metallurgical study involving next generation magnets. These types of furnaces are typically hydrogen fired, but for my process, the induction heating is vital. The temperature control needs to be within a 5 degree tolerance. Outside of this window, and the very special properties I'm investigating and manipulating diminish quickly.
This shit is amazing! So excited to watch this channel
Thank you for your encouragement. It really means a lot to have so many people interested in such a niche video :)
The thermocouple was rated for 1000°C but in vacuum. In air the stainless steel oxydize and do that (I'm not sure but I think the black oxyde is chromium oxyde)
Possibly! I was looking around and I didn't really see any other thermocouples rated for 1000C that had that metal shielding- most were the ceramic shielded ones. I'm about 50-50 right now on your explanation vs bad amazon listing.
@@projectsinflight I use a thermocouple with stainless steel shield at 1300°C at work in a vacuum kiln it works 100%. But I've tried once to put a bloc of stainless in a kiln at 1000°C in air, the result was exactly the same!
But ceramic is the only solution if you aren't using argon or other neutral gas
Awesome work! Please continue this series! Cheers
You are excellent. Your channel is a piece of art, your filmmaking skills are stellar, your narration is captivating. I can't get enough of your content. Never quit!
Reminds me of Ben Krasnow. Very impressive.
I've been a fan of his for 10+ years ever since the SEM project. I really hope to have my own one day!
That thermocouple got absolutely COOKED. The way it was popping and crackling and peeling off oxidized layers was crazy.
Looking forward to seeing more stuff from you this is awesome
A series of how to do semiconductor manufacturing at home? I'm all here for it!
Id say look into exhaust paint rather than engine paint. It has a lot higher temp rating and works pretty well. That said cant say for sure if it doesnt act the same as barbecue paint since ive only used it on heatshields
so far people are suggesting brake caliper paint which seems appropriate. I've got to look into the pros and cons of each type of paint. Who knew every component of a car has it's own special paint lol
So happy to found another channel like Applied Science and The Thought Emporium, instant subscribed after this video. Can't wait to see your future projects.
Brilliant work! Really interesting to see the way you secure your nicrome wire. Cheers
I dont usually subscribe to a channel with so few videos. This popped up in my algorithm and it was so well done and interesting i could not help myself. Please fo not let the UA-cam "why dont you... i could do it..." want a be's grind away at you. If you had a Super Thanks i eould have immediately sent you some $$$. I will look at your Patreon if the content stays this good snd the narrative so quasi professional. Thank you and i hope you post a lot more. You give off the learning/experimenting glow I used to have when i was young! : }
Thank you for your support :)
Another Breaking Taps type UA-cam channel; and I am loving it. Keep it up man !!!!
Thanks! I'll do my best :)
I've been watching your videos and it's bingable for me. I always dreamed of doing this but unfortunately I'm disabled and have very little money, so now i get to live vicariously through you
For the wire connections you'd probably want high temperature crimp connectors and silicone coated fiberglass sleeving for electrical insulation on your passthroughs.
Commercial ovens use alumina tubes and ferrules and woven fiber glass tubes as wire insulators. Also, thermocouple can have alunina insulator around it.
Wow, this is perhaps the most thought provoking video I've seen in several years. I smashed the subscribe button so hard i was concerned that i had broke my phone. Thank you so much for this video, will save me a fist full of cash
If you want to do this really cheaply i'd actually recommend looking for a used tube furnace that is really old and junky. You can often find incomplete furnaces with just the heating element, thermocouple, and insulation for less than $100. add the controller yourself and you're done.
Looking forward to more content from your channel! Your video was very interesting and I even learned a few things I hope you post more soon thank you for your time and trouble!
Engine enamel needs to be baked. Brake caliper paint is a good option if you want to use paint without a heat curing cycle
Ooh this is very good info! Thanks
This is definitely the most entertaining content I've seen in a while, keep doing great 👍
thanks! I'm excited to show some of my upcoming work!
Sheet metal screws fasten from one side; they're the middle ground between pop rivets ($) and solid rivets which need access to both sides. Also there are ceramic scissors (ostensibly for Kevlar jacketing on optical fiber) that might be better for that insulation.
Nice project! In the future, instead of blue tape, secure the wire with Kapton tape. It's useful range is up to 260C (500F).
Yeah i am 100% ordering some now!
this is so interesting... I can't wait to see you build diodes and transistors
amazing work, looking forward to see more videos like this, i wish you the best sucess in your goal of fabricating a working semiconductor.
Thanks! I hope to have some devices soon
Dude, I hope you're not just yanking my chain. This is really great stuff. Since Sam Zeloof completely gave up on making videos in favor of running his own fab, we need another hero to take his crown. Homebrew semiconductors needs to become a thing.
I can say with confidence that I will be able to produce SOME kind of IC, but exactly how well it performs is a work-in-progress right now
that´s some good stuff
Thanks! I appreciate the encouragement :)
Great project and many good tips!
Found Your channel by chance and subscribed, much of what You do resonates with me....
Some minor tips that may be useful if You have not seen them:
I have made some heaters with nichrome wire and a good reliable way to to terminate the wire is is to twist it back on itself and terminate on a copper block with a screw through the loop (or a copper ferrule). Twisting keeps the connection cooler. Perhaps khanthal wire would be better if You need over 1000C, but then You can not use that silicate cement. Use porcelain and fiberglass insulators. I salvaged fiberglass wire from our old cooking stove. I also believe quartz will have limited lifespan above 1000C, maybe a slightly more expensive alumina tube would be better. They seem to be available fairly low cost nowadays. Have no idea about out gassing etc though for Al2O3.
this is extremely interesting. this is exactly the same concept behind rebuildable DIY vaporizer works. I got into vaping around ten years ago and was able to quit smoking. and I've learned how to wind my own coils and whatnot, basically this is exactly the same principle behind how that works
minus the quartz tube of course
I imagine if you stay much smaller tube though you could create a really interesting dry herb vaporizer bong with this LOL
Haven't exercised the neurons that learned (the rudaments of) this at undergrad in about 20 years - thank you! Also, incredibly happy to see that one can push semiconductor manufacturing into the bounds of DIY. To be less serious- def tabbing this Primitive Technology video to prep for the coming zombie apocalypse 😂
Interesting, thank you. I did not know the colour of the oxide coating related to the thickness of the material. Subscribed!
Awesome!
Cant wait to see incoming videos!
Please make more content your few videos so far have been amazing!
Thanks, i definitely will do that
0:09 ....what is the metal organizer called so i can buy one ...the thing in bottom right under your workbench
It's some kind of office file cabinet thing. I got it from one of those commercial area garage sales.
For the wire wrapping you could use a spacer of another wire, or a thin strip to ensure an even distribution that won't shift as you apply the compound over it.
This is a great video. I was just browsing online for used tube furnaces and came to the same conclusion as you did, far too expensive! My next thought was to DIY, I'll be using your video as a guide to create my own tube furnace. Well done. Thanks for the video! P s. Ive seen thermocouples do that at high temp. Anything above 750c will cause them to act funky.
definitely recommend using ceramic fiber insulation for the wires instead of heatshrink like in the video
7:22 it's not Conducting heat instead the Heat is Leaking in IR form so may be you should use any reflector between tube and insulation or place reflector like Steel foil between insulator so it will be safe from heat and prevent ir leaking.
Interesting- i might try that and see if it helps
Bro these videos are AMAZING.
Thanks for watching!
@13:40 if you use a drill or electric screw driver, your wrist will thank you later
Haha! Would you believe that my power drill actually died on that exact day? I was so sad
Well there's the answer I want looking for but I'm glad I found it. I'm subbed. This was a cool project.
Prepare yourself for so many answers to questions you didn't know you had. At least that is how i've been feeling while working on my next video lol
@@projectsinflight for years I believed that it had to be possible to make my own hi temp kilns but I couldn't wrap my mind around how to do it. Thank you for putting this video up so I can see it done and in a really interesting way. Do you think borosilicate glasses would fuse to the quartz glass? I'm picturing a 3" diameter set up like you made in this video . I would be putting class smoking pipes in it to aneal in between working processes
You can also use ceramic beads for wire isolation
Endoscopy tweezers will fit inside the tube. Only the tip opens. They use rack and pinion or something down the shaft.
Oh that's awesome- i'll take a look at these!
Instant sub earned. I would try to replace the massive stainless steel rod with a thermal capacity of a bazzillion with something less thermal shock inducing. Like a burnt out core of a very long carpenter's pencil or something, to stay in the DIY realm, although you should not burn it inside your tube, as metal vapor would probably contaminate your tube forever.
I wonder if you put a stainless steel jacket over the outside of your tube if it'd help with temperature evenness and getting a bit of thermal mass to help with stability. It'd essentially be a consumable though I don't think it'd be too happy up there. You might consider a triac type arrangement rather than the SSR as well. You won't have much thermal mass in the wire so I think you'll be getting much larger temperature swings than what you're measuring especially with the amount of thermal transfer that'll be done by radiation rather than by other means. Aliasing from that effect might be something you're seeing with your stability.
There are arduino triac boards and code that are meant to just plug in but I haven't used them yet.
Great video mate, really keen to see how you progress with this.
If the barbeque paint needs high temperature to cure properly into a hard enamel, you could always broil the painted parts into the oven to cure them.
I thought about it but i wasn't really comfortable doing it in an oven used for food. if i get access to a suitable oven i will definitely try that!
@@projectsinflight Yo dawg I heard you like ovens so I got a new oven for you to put your new oven in
@@projectsinflight You could take the insulation out, insulate the Copper cables with fibreglass sleeve or ceramic tubes and then use the tube furnace to bake the paint in place. Do it outdoors though, might need to insulate the box from the outside with some rockwool and longer cables to your controller.
@@benlee4940 Even with insulation on the outside, that might risk too much / too rapid temperature change for the quartz tube to survive.
Oh McMaster carr. Try Wale Apparatus next time. You could get a full 4 foot length of quartz for $20. Ed fagan for metals.
Darn- I just put an order in for tubes from an ali express seller. This whale apparatus thing is a good find though- thanks!
@@projectsinflight semi conductor world is linked to glassblowing. A cheap mini torch and hydrogen/O2 can easily work quartz. Propane/O2 can but is still dirty (for making boats and sputter material boats. When working quartz, the quartz will out gas SiO2 that condenses as "cob webs" be advised for fumes. I've fancied working colored borosilicate glass to out gas heavy metals from the stoichiometricaly denser colors. Colored glass is chemically inert, vs storing pure toxic metals I may need micro grams of (it's artsy fartsy chemistry, batches and mixtures are not pure or may be guarded trade secrets.)
I think you can sculpt some "horns" on the ends of tube when placing that clay-like material. That way it will not slide out of case ever.
it didn't really come across on video but just the friction alone was enough to keep it thoroughly immobilized. it shouldn't be in any danger of sliding out as-is (famous last words lol)