Thanks Guys. You have been great over the years. You have enough knowledge now to move on and come up with your own innovations. Mean while i am going after life long dreams. Love you guys
@@adrianmucci4860 Graphite is mainly for non ferrous casting. You would be better off making a lot of disposable clay crucibles for iron or steel. Dry them in in the oven then fire them in the foundry. Make sure you have driven all the water out before ramping the heat up. Boiling Point of water at your altitude is critical point in the oven. My oven was 20F lower and i blew one up once i started ramping the temp. use high temp probe or thermometer.
@@rlbob1would this be sufficient to cast aluminum oxide (Al O3)? I want to make an ingot of corundum / ruby / sapphire. Honesty I was thinking of putting down a sheet of corundum and adding the chromium and other dopants to “paint” a design on it, hopefully getting the temperature just right for it to fuse and turn into ruby and sapphire without losing to much definition. I’m planning on using either map gas, or hydrogen + oxygen as the heat source. That should be sufficient right?
@@Olisha.Sahahha! growing crystals is a very complex thing, there are various processes and lots of machines have been made, that cost up to quarter of a million bucks. You can't just expect heating alumina and magically for it to convert to sapphire, the atoms must be excited and then cooled to find the lowest energy spot between them, this process requires very fine temperature control and engineering, otherwise you will just wast energy and lose money. Check out how the grow sapphire cylinders for smartphones.
Most of what this Gentleman has revealed would in fact be proprietary knowledge / Trade secret of firms. Amazed at his out of the box thinking ! No words for his Genius ! Thank You Sir & My Respect !
First of all yer a God Damn CHEMIST my friend and second,FINALLY someone wearing proper aluminized safety protection! I used to run a 2 million pound a year aluminum smelter and the number of people on RUclips running around in tshirts melting metal with zero safety gear on just blows my mind! Great video!
My idea why they dont use proper safety is that the metal doesnt glow red hot. People are generally afraid of red hot metals but not metals that look molten similar to when solid.
Thanks so much for posting this. I have wanted to build my own crucible for a while now and after seeing all the hard work you put into that beautiful crucible, I think I'll just buy one. Again thanks for posting.
This video was mad 8 years ago, has anyone tried it and please post links to any videos with improvements. Thank you good sir you will go down in history as one of the best backyard engineers. Always wondered how crucibles were made.
Happy New Year bud...... You are the man! I am so happy to see the dedication hard work and pride you have for your craft! I am a novice but learning and taking things slowly.... I was wanting to make my own crucibles just like yours so I am so happy to see it can be done! Cheers!
brother you looked a little shaky at first, but you are the safest and one of the smartest casters on youtube period. i think your work is excellent, that same starbide crucible would cost 200 plus bucks..a spectacular job, i am very impressed, and i'm not easily impressed kudos
Its all new to me the method you are using and there may be strong reasons why you do. However i come from a ceramics background where we were slip casting. That is getting all dry clay ingredients adding to barrel of water making thick slip clay, adding deflockulent.which makes it appear thinner, more wattery. Then we added slip to dry/ semi dry plaster of paris molds. The benefit is there is definitely a higher success rate/ failures due to cracking. Dont know of this helps but just what i know
I don't think I can properly express how valuable your video is, Sir. I have to try it on my own! From what I see, a meat grinder should come in handy for homogenizing the mix. If you ever test it, please post what the results are. Many thanks for your work, Sir! You're doing us a great favor!
I noticed when you were hand-mixing that you started kneading the stiff clay immediately after wetting it. When I want to "thin down" stiff clays a bit, I prefer to add the clay & a bit of water to an airtight container, then forget about it for a few days. Letting the water work its way into the clay on its own is far easier, and makes for a much less slimy experience, IMO.
Hi, glad to see someone else uses the wife's oven to make furnace parts. I also know what I can do with the 15 to 20 pounds of graphite powder I end up with after making molds every month. Great video, I'll give it a try but on a smaller scale.... Nice job
He was using a hydraulic jack to compress the rings with the collared steel tube he showed you in the beginning. @rlbob1, did you score the ring segments before setting them in the mold?
He didnt show how the mold goes together, or how it is oriented in the press. It's not clear or detailed how he packed the clay nor did it show what keeps the clay from just pushing out the bottom. How did he end up with a solid bottom if he is using a hollow ram with a flange? No information on that. How thick is the walls and bottom? Not a clue. At 10:24 you mostly see his back not a clue what he is doing there. At 10:34 he ducks down so who knows what he is doing there. All the camera shows is the same large tube with a hex flange. Whats the large tube with the hex flange for? Between 10:24 and 11:21 he shows nothing of what he is doing. Between the beginning up to 7:40 its a great video. Between 7:40 and 11:21 not so much. After 11:21 he shows what is going on again. Like most things in life you never get the full story from one source.
Unfortunately the solid steel tubes did not allow much for camera angles so I had to rely on the storyboard in the beginning. Still I think I can answer most of your questions. The large tube with the hex flange is bolted to two 2*4's which straddle the concrete blocks and firmly hold the smaller tube and the core base in place. The large washer on the core base fits snugly against the end of the flared portion of the small tube and keeps the clay from pushing out the bottom. It also centers the core and forms a nice flair for the crucible top You recall the hollow ram also has a solid end as well as the washer end. After building the clay to the top of the core you flip it to the solid end and add another inch of clay for the solid bottom. The solid end is also used to force the crucible out of the mold after unbolting a board holding the core base in place. Just remembering it is being formed upside down with the flanged top facing down and the solid bottom up and that will help visualization.
Sorry I have been away so long. So many things happen in life which make filming RUclips videos seen trivial. I did make an experimental crucible but lost video and formula. Had the crucible professionally fired but owner of shop was so leery of it she fired up the whole kiln with just my crucible ... nothing else. Well in its raw unfired state it does like its made of gunpowder. Let me dig around a bit ... maybe i can retrieve it from old drive. Love you guys and gals. bob
Glad to hear you are alive and kicking. I get the thing about things happening in life- death in the immediate family, new job, house burnt down in the forest fires, global pandemic… been there, done that, got the t-shirt. Anyway, life does go on. I’m sure many people here would like to see your new formula. I’ll admit, I’m leery of putting glass (even powdered borosilicate) in my mix as I mainly melt cast iron and my experience with glass is that if any silica sand gets into the furnace it tends to melt into glass, making a sticky mess that can sometimes get between my plinth and crucible. Over the years, I’ve been through a few $$$grand’s worth of Morgan super salamanders and I’m getting tired of it. Asbury graphite isn’t too far from my shop and I can get bagged fireclay and grog locally too. I bought the Vince Gingery book on making crucibles many years ago as a curiosity and his formula, for a 3 pound mix (page 23) is “Hawthorne bond 35 fire clay, 38% or 18 ounces. (Or other fire clay may be substituted.)”, “Potash Feldspar 2%, or 3/4 ounce.”, “Brick grog 20 mesh 60% or 29 ounces.” He doesn’t say anything there about the graphite, but on page 21 he says “The graphite content of such crucibles is normally in the range of 30-40% or the total weight of the crucible”, so it could probably be scaled into the clay/grog mixture. He also says on page 7 “Typically a good clay was mixed with 20 to 40 percent of its weight of graphite” Those numbers seem pretty in line with yours. He mentions that of the amorphous and foliated/crystalline, the crystalline is the type used for crucibles and lubricants and the amorphous form is used for lead pencils, foundry facings, electric brush carbons, and paint pigments. I will probably give Asbury a call and see if one of their application specialists can recommend a particular product. I get the feeling from their website and elsewhere that they carry 50 or 60 different graphite products, varying in mesh, crystalline versus amorphous, and intended use. I got a 20 pound bag of powdered graphite from Budget Casting Supply years ago when they were still selling it (they’ve been ramping the business down for the last year or two, selling off inventory), but I don’t know what the intended purpose was. I’m using it as a mold wash for my gray iron castings to help it not melt and stick to the sand, which is a pain to clean. I don’t assume that just because it’s powdered graphite that it’s appropriate for crucible use. Anyway, thanks for the video. Glad you’re back! Definitely please share your recent formula (with the obligatory disclaimers, if need be, though most of these jokers commenting are just arm chair warriors and won’t actually make a thing in their lives anyway). I’ll be doing some experimenting, but it feels like a waste of time to reinvent the wheel or duplicate effort that’s already been done by others before us. Thanks again.
Would it be possible or beneficial to use aluminum oxide powder in the mix. Maybe a small amount. The reason im asking it is used to make the ceramic insulators on sparkplugs , and handles great temperatures . It is inside the combustion cgamber , and even seen the sparkplug electrodes melt, pistons melt. Have specks of piston splattered on the ceramic. And tge only thing i ever seen happen to the ceramic is a crack. Even seen people use the ceramic to spin form steel . Where the friction heats the steel allowing it to easily be shaped. Even welding it. So it seems the powder in with graphite could possibly help the graphite withstand temperature. Instead of the boracilicate . I had the idea that i may look into playing with some red clay used to make brick.. and mix it with graphite or carbon, possibly both. And look into possibly adding aluminum oxide. Use distilled water to prevent adding metals frim the chlorine corroding the pipes. Make a "mixer" by putting two wheels on a axel about 6-10" apart. With a gear reduction motor spinning it at up to 25-45 RPM. Tge wheels doing round in the bottom of a cut off 55 gallon barrel. With the bottom 1/3-1/4 bring used as the mixer. With a 1" piece of plywood bracing up the bottom. The wheels made from a chunk if hardwood tree trunk about 4" zo 6" thick and azleast 4"- 6" thick a pair of wheels from oak or something 6"-7" thick and turned down im a lathe to about 12" diameter. After spending the day imw oven at 250°f- 300°f, keeping an eye on it to see it doesn't get any darker than a tan use a lightly pressed and epoxied in steel sleeve in tge wheels . And another onto a 2"-3" axel made from a chunk cut diwn to 4" x 4" with a 1/4" steel plate bolted to the top and bottom with a .375" keyed 1.5" steel shaft to spin the wheels , tge shaft being 12" longer than required to just spin The wheels and spindle. The shaft being roughly 16" long with a bearing block mounted center of the barrel with the shaft inside. making it look something like part of a clothes washing machine. The shaft below the bottom being about 6"- 8", (5"- 7" with the bearing block) then a roughly 60 tooth sprocket, then another bearing. Connected to a 2.5" bit of channel ,running from the leggs on the bottom of the barrel. Being about 14" long legs.the motor attachef to the inside of one leg, having a gear reduction to 250 RPM, (-/+), them s 10: tooth driving a 60 tooth (+/-) (maybe a 40 tooth) the wheel spindle being able to slide on the shaft , not spin. The steel inside the wheels having oilite bushings pressed on. Using a steel washer on the wheel. With a rubber washer then a large leather or treated paper or cloth washer to seal out dirt from the bushing. Zding a large C clip on w groove in the steel on the spindle. To retain the wheels. The shaft having a threaded hole with 1/2" bolt 1/2" deep. Used to retain the spindle uding a large 1/4" thick washer about 2.5" -3" dia. With a spring fitting around the shaft. Pushing down on the spindle with an adjustable pressure from about 10 lbs to about 50 lbs. The wherls capable of moving up and down about 10"-12" or so. The spindle having two 2 steel angle bars. Running out from the spindle to the barrels inside wall. Being about 1/8"-1/4" from it. It having a roughly 2"x 4" bit of rubber bolted to it. Possibly a piece of car tire sidewall. Used to gently rub the inside wall scraping any material off it. Putting it under the wheels. And possibly have wheels or rollers to attach to the bars, rollers bring they wound be about 2.5" dia. Abd 4" tall. However the scrappers will likely do best. With a large PVC coupling under the spindle shaft to keep material away from the shaft. The speed of 45-60 rpm max. slowly add matereals and a fine mist of water. To jeep it dry as possible. Possibly the best speed would be 10-15 RPM . Euth a speed controller. To set the speed. And seal the wood parts and wood wheels with a clear epoxy, thinned to allow it to be absorbed into the wood about 1/8" of the outeside , dependibg on type and density. Then apply a thicker coat to the outside for a tough exterior that should not rot. Being hot dried. Tfe thinned epoxy could completely soak in. Especially if a pressure /vacuum chamber is used. Remove all air from the wood replacing it with epoxy. Completely stabilizing the wood . Making it a composite material. The wheels being 1/2" smaller on one side than the other. With them being mounted oppositely , pushing the material back and forth as they roll over it. With a lid from the barrel to prevent dust. And it should nearly be a professional pos, uh um, poe, piece of equipment! 😅 ✌️... then make a furnace from the rest of the barrel and another. Having 3 , 7' bits if 1.25" -1.5" even 2" pipe, with them connected at the top by 2" angle steel, 1/16-1/8" thick, the bottom doing the same by forming a 36" x 36" or 42" x 42" square. The pipe welded at the corners. A bit of 1/16" sheet steel welded to the inside bottom square. Fill it with concrete. Possibly add a 1" x 6" board to the outside of the angle, then fill eith 6" of concrete Locking wheels can be used under the steel frame. Then a barrel bit 6" - 8" thick placed on the center of the concrete pad a piece of rock wool or other insulation that is solid , and handle higher temps inside the barrel then pour about 4" of refractory mortar inside the top of the barrel. Mount a hand crank winch to the pipes to a bit angle bolted or welded to two pipes, and a bitbof 2.5" channel steel crossing the top. To mount a pulley to tge center of the square. (Use a hand crank winch or a small electric winch as long as it moves the cable fast. Then cut a hole about 6" im the center of the bottom of a barrel. Use about 3/4 of a barrel. Then cut both ends from another barrel naking it the same length. (Or buy a piece of 18-20 gauge sheet metal . Roll it into a tube smaller than the barrel. Leaving about 5"- 6" on each side of the tube. Drill several holes in the barrel 1/4" use all thread aka threaded rod. To go between the barrel and tubei 6places. Then at least 3 holed in the bottom of the barrel then drill three, 1/2" holes evenly spaced near the outer edge. Install 3, 1/2" eye bolts , with a 1/4" rebar welded to the threaded shank. 18" long, eith a fender washer welded to the end of the rebar after the Eyebolts bare installed! And optionally, bend a bit of rebar into a ring about 4"-6" saller than the barrel. Weld it to the fender washers. Then mix refractory mortar with saw dust, about 5 lbs of saw dust and fill the gap with it. Between the barrel and tube with it. When it's set, fill the inside of the tube with extreme temperature wool wool used in furnaces, to handle 2°-3°k f. Used in assay ovens and such. A 1" single layer should work. Then flip it over attach chaind 12" long to the eyebolts. To a single centered point. To be lifted by the winch. Lift it and sit it on the insulated portion of the pad it should weigh about 40lbs. Drill a 2" hole in the top for a 1.75"- 2" pipe , with it capped in the bottom ofvthe barrel then drill three 1" holes about 4" from Beach other the bottom/end pipe 2"-3" long welded in the larger pipe aimed up at about 15° up 4" at the next pipe it's 90° from the pipe all also aimed about 45° from center of barrel. Then moving up about 6" welding on the next 1" pipe , aimed down at about 10° . With a 1/4" steel tubing running inside the larger pipe having 3 outlets. The with a cap threaded on to get a roughly .060" nozzle in each. And possibly add another pipe with more nozzles. With with another gate valve to adjust fuel. And connect a electric leaf blower by flex hose to the 2";pipe. Having a 6" Radiused 90° elbow at the top. And a 12" pipe with 3" barb to clamp a hose to the pipe. . Capable of spraying propane through the nozzles that are inside the 1" pipe just as it opens up in the larger pipe.. the fuel having a fan spray pattern. With a single trio of nozzles capable of a 20:lb propane bottle in about 8hrs. on med. And possibly use the secondary nozzles to spray used oil. And crank up the air flow. And btu !🦾.. possibly exceed 3°k F and add a barb fitting to connect a o2 hose. To get possibly 45% o2 in the air flow! to = 🔥 HOT possibly overheat the insulation. The furnace lifts off the crucible. Making it easy to lift. Then the heat stays inside the furnace. Just close the top vent. The hot air stays inside. lift off the furnace from the crucible Making the reloading easy.. dirty to ramble have an awesome day🎉!
I'm looking to make a crucible to melt more-or-less pure quartz (silica). It melts around 1700°C. A pure graphite crucible melts around 3600°C so I think that'd work. But...do you have any idea if your graphite crucible mix could work up to around 1900° (I'd like a little temperature buffer to work with since I might have to run at 1800°C or so). I suspect since glass is a component in your mix it will cause your crucible to fail when the borosilicate melts, which is apparently 1648°C...although sometimes mixes have surprisingly different properties so maybe it could withstand higher temps? Have you ever tested it?
Some of you have not seen D he touches blocks of just set blocks of aluminum with almost bare hands it nuts how you people endanger your lives. Thank you Loader.
This was a very well presented diy. I noticed you don't reply to most questions. But here goes Can that mixture be used for molds? Would having the clay in powder form be a good idea? And a question I see asked is will this work to melt steel?? Thank you for your time and effort in sharing this video. It's the only one I have seen for making clay crucible. Thanks again and have a great day kind sir!!!
From everything I've read trying to find a source for a crucible w/ which to remelt some steel, any graphite crucible will just leach carbon into your steel and you'll end up w/ cast iron & a (severely?) compromised crucible. Any attempt to melt iron or steel has to deal with a couple of issues: protecting the melt from oxygen in the air [since the kindling temp of steel is below the melting point] (which is apparently normally accomplished by a layer of molten glass on top of the melt) and a bottom-pour capability (because the protective glass layer would form inclusions & other flaws if you tried pouring from the top.) I figure one of the small inductive furnaces sold for Al, Cu, Ag, Au melting would be fine, if one used a bell jar approach to evacuate most of the atmosphere & then introduced argon [widely & cheaply available from welding supplies;] the minimal surface exposure from the deep, small diameter crucibles those units require would enable one to pour a casting w/o compromising the batch, but nobody seems to offer a suitable crucible, just the graphite variety. Probably because of liability concerns... pesky injury lawyers! 🙄
I am a bit familiar with ceramic slurry casting. as that is for dishes, cups, and decorative items I know that such clay would be a poor idea for a crucible. that's not what I was thinking though. for those who aren't familiar with it, its simply pouring liquefied clay into a mould and keeping it full for a certain amount of time. that is where my question comes in: can you add enough water to make the graphite clay into a thick slurry and cast it in much the same way with at least a reasonable success rate?
been thinking about having a reasonably tall kiln and cruisible combo where i can put in a complete cilinderhead (unbroken with valves springs everything still in it ) i seen it done once but the guy used a verry large burner putting the flame staight in the opening against the aluminium inside a steel barrel layed down at an angle with the catchcan under a hole in the lowest point , verry crude and wastefull in the amount of energy used to melt it but it worked the dross basicly stuck to the barrels wall on the way down while the pure aluminium dropped further and out the hole like to try it with the kiln vertical and the burner as is normally placed and have a hole in the bottom of the cruisible sitting on a hole in the bottom of the kiln , the kiln sits higher off the ground then usual and the mould is placed under it (want to make clean aluminium ingots that can be remelted and cast the normal way ) my thought is basicly to not spend a lot of time pouring or even take out and handling a red hot crusible , taking out dross and all that but just have the aluminium leak out the bottom at the same speed as it melts off the head and keep adding scrap through a hole in the top and having moulten aluminium pour out the bottom any idea how to get the dross to seperate while the aluminium drops out ? will it stay in the crusible or block the pourhole ? if the dross comes with the aluminium leaking out i was thinking on a small gutter from the leakpoint down to the mould for the dross to stick to , but it might be too cold and have the aluminium solidfy before it enters the mould or just make a bigger mess of things
Very nice job. Don't feel like it was too long. I would liken it to watching Julia Childs. Where most cooking shows give you a whiz-bang kind of presentation, hers really walked you through step-by-step. Incidentally, in some recent research I did find someone mentioning to glaze the crucible with silicon carbide powder. I cannot really comment on its effectiveness, because I haven't tried it yet.
I'm looking into casting metals, starting with aluminum, and I wanted to get clean non-ferrous pours to maintain the strength of the alloy for use in machine tooling. I did a search for fire clay and the closest I could find was "low-fire clay". Is that the same stuff? Also, I was thinking while I watched your very informative video that adding even a slight taper to your forms would make it easier to extract them after pressing. Has anyone tried this?
I am using a ready mixed ceramic clay called "woodfire" in the video. Clays of this type are available at ceramic shops for making pottery. Try to find a clay that fires at the highest Cone they have available. Google "ceramic cone fire chart" for more info. Other options are of course steel crucibles, stainless,ceramic clay, etc. Steel does not last long due to the corrosive nature of propane. Stainless would be great but it requires Tri-mix shielding gas and stainless wire to weld with a MIG. Very expensive. Clay as I described is cheaper than steel and will last longer. You could make a crucible mold out wood divide it into 3 or more sections bolted together and ram it by hand. The core is a problem when you start making one any larger than a drinking cup or glass. It sticks fiercely to wet clay due to the suction of the vacuum created trying to remove it. Hard as it is to imagine this effect is so great even a heavy bulldozer can get stuck with the right mix of clay, mud and the vacuum effect. bob
Silicon carbide can be obtained from ceramic insulators used in various applications where nicd coils are used? Borosilicated glass can be obtained from pyrex glass? Graphite can be obtained from the back of old style tv tubes and computer cords? Are all these assuptions correct and fire clay is there a free place to get that?
I'm a amateur mechanic. I really like the foundry work, melting metal. I have a lot of car parts anything from aluminum heads, to steel leaf springs. I figured instead off tossing them why not melt them into other things. Use the old things to make New things. Aluminum heads no problem melting. 1095 steel coils very different animal. I figured if I can melt steel then everything else would be easier. Thanks cont.
What formula would be needed for the silicon carbide crucible? Substitute the graphite for the carbide and use three ingredients, with a high grade fire clay I surmise...
While it’s been over seven years ago and prices changed and product availability may have gotten more complicated (or not), I’m curious as to what it cost to make and about what volume does this one shown hold. My small-ish (A5?) was about $35 if I remember correctly (I probably don’t).
I love that fricking suit dude.. .can I rent it for Halloween? lol Great video... I am going to use some of your procedures, and tweek others to fit my taste. :)
Is there any particular grit size you are using for the silicon carbide? I have some 150 grit and some 1200 grit any benefits to one grit over another?
thanks for your video,yesterday i made research on the net and found out about lost foam casting and slury for better surface."The prepared foam patterns were then dipped for 60 sec. into a slurry made of a mixture of Zircon flour and colloidal silicate".You can find out some more if you Google article;Process Control of Lost Foam Casting using Slurry Viscosity and Dipping Time
The crucible can be enhanced with a sacrificial coating, painting on a well mixed slurry of plaster sodium-silicate and graphite every few times you use it. Just to give them a longer service life, since it does take a bit of time and money to make them.
One tip on clay: it resists water absorption if it already has any water in it, so you could pre-weigh it for your formula, then let it dry completely out. Completely dry clay absorbs water very readily and it's easy to make into a paste. By the way, what kind of metal are these crucibles for?
Dude awesome AWESOME video. Thank you so much for the exact recipe to make my own. I know it could get spendy buying them. Glad you taught us how to save money. I do assume we can save clay for later if we do want to make smaller ones?? or should i just cut the recipe in half?? just lil curious because i dont want to use a large one all the time.. Once again GREAT job on the video. Makes it easy for some ppl like me to follow along.
what size is the dimensional size of the crucible and what is the amount it holds , I won't be working with large amounts and wonder if it will be worth the effort and cost to make this
This gave me some ideas on what I need to do, I want to make a crucible that will accommodate the irregular shape of my furnace and not waste any space but concerned about the heat flow as well. I don't want to break down its efficiency so any suggestions would be appreciated as for the fire chamber coverage
At the time sold on Ebay as used Military surplus. Called a proximity suit used by Navy aboard ships. Probably all gone now. Pants and coat were cheaper than jeans at the mall.
ive found if you roll out your clay real thin, sun dry it and then crush and powder it. you can mix all the dry ingredients like a cake then add just enough water to make a air free mold. pack it and is way less work to get a extremely even blend
altazink Good idea. Still it would be better to use some type of motorized device to crush it. Maybe a large steel roller filled with lead on a motorized turntable. That could also be used to crush the glass from scrap Pyrex but be sure to make a cover for it. Glass as you know pops many feet when it breaks.
2nd the ball mill. It also seems extremely helpful for mixing green sand. I found an old steel hollow ball. I believe it was a tank float? Figured full of lead it should weigh 30 pounds or so. Should be plenty of weight to press the ingredients together. Far as i know anyway.
Hi Bob, so 2 things I'm curious about. 1- you spoke of a new formula you had a few years ago. Has that worked better for you and would you care to share? 2- with these crucibles, once you do the slow process of bringing things up to temp for your first pour; do successive pours have to be slow as well? In other words my crucible is setting around for 2 weeks. Do I need to heat it up really slowly when I decide to do some casting or can I just ramp up my foundry furnace on waste oil like I normally do with a steel crucible?
@rlbob1 absolutely genius of our time, I do have a question, what would be the cons of have a stainless steel reinforcement in the mixture, similar to the technique of reinforcing concrete, seeing as stainless steel melts at a temperature far greater than what a home foundry could ever produce?
Have you tried mixing the ingredients as powder? As far as I can see in the video everything except the clay is dry. I would cut the clay in thin slices, let it dry for a couple of days and break it to small pieces. Once everything is mixed properly, add the water.
I'm interested in your technique. I CNC engrave graphite Metal moulds and end up with a lot of plumbago graphite powder and want to recycle it in a graphite ceramic with clay and sand for spin casting moulds. But my attempts to make my own water glass -Sodium Silicate from sand with Lye -Caustic Soda) as part of the Mixture got me into a caustic mess. I have Neutralised and am washing out .
You might want to try Ins-Tuff Ceramic Blanket Rigidizer. Be aware it is highly hygroscopic and takes a while to dry. If you have scraps of ceramic blanket you can also experiment with milling and screening to a powder to strengthen the graphite/clay mixture.
I know the video is 6 years old, but if you see this I would love to know how do you clean the residue metal out from the crucible? Or do you use one for each metal?
One for each metal. Never leave any metal in a crucible. Dump on ground if necessary. Residual as long as no button left in bottom will dross in next heat. Otherwise it will crack crucible.
Trying to melt approx. 56 pounds of steel. I have 55 gallon drum, 2 in. 3000° refractory all around , 2 in. 2600° ceramic blanket. Not assembled yet. Any advice greatly appreciated.
Thanks Guys. You have been great over the years. You have enough knowledge now to move on and come up with your own innovations. Mean while i am going after life long dreams. Love you guys
Thanks for sharing this information. Is pure gold. This formula is enough for cast iron? Sorry for my English.
@@adrianmucci4860 Graphite is mainly for non ferrous casting. You would be better off making a lot of disposable clay crucibles for iron or steel. Dry them in in the oven then fire them in the foundry. Make sure you have driven all the water out before ramping the heat up. Boiling Point of water at your altitude is critical point in the oven. My oven was 20F lower and i blew one up once i started ramping the temp. use high temp probe or thermometer.
@@rlbob1would this be sufficient to cast aluminum oxide (Al O3)? I want to make an ingot of corundum / ruby / sapphire. Honesty I was thinking of putting down a sheet of corundum and adding the chromium and other dopants to “paint” a design on it, hopefully getting the temperature just right for it to fuse and turn into ruby and sapphire without losing to much definition. I’m planning on using either map gas, or hydrogen + oxygen as the heat source. That should be sufficient right?
@@Olisha.Sahahha! growing crystals is a very complex thing, there are various processes and lots of machines have been made, that cost up to quarter of a million bucks. You can't just expect heating alumina and magically for it to convert to sapphire, the atoms must be excited and then cooled to find the lowest energy spot between them, this process requires very fine temperature control and engineering, otherwise you will just wast energy and lose money. Check out how the grow sapphire cylinders for smartphones.
❤whoever smelts the gold; makes the rules 😅😂🎉
Superb video from a humble engineer - "please send me your improvements, I'd like to try them out". People like this are gold-dust.
they're the whole nugget bro
I thank you for educating me and taking away years of frustration from my life.
Most of what this Gentleman has revealed would in fact be proprietary knowledge / Trade secret of firms. Amazed at his out of the box thinking ! No words for his Genius ! Thank You Sir & My Respect !
First of all yer a God Damn CHEMIST my friend and second,FINALLY someone wearing proper aluminized safety protection! I used to run a 2 million pound a year aluminum smelter and the number of people on RUclips running around in tshirts melting metal with zero safety gear on just blows my mind!
Great video!
CdnCarWrapper or barefoot. Dumbasses
I think the main reason people don't use this kind of gear is because they don't know where to get it from and if they do don't have the money
My idea why they dont use proper safety is that the metal doesnt glow red hot. People are generally afraid of red hot metals but not metals that look molten similar to when solid.
I only smelt in my crocs... 👷🏽
Exactly. When we were kids we played with melting lead and nobody thought it was a safety hazard. I had the pot almost explode several times.
A visible demonstration of one determined guy,I salute you.
Absolutely incredible, sheer talent and professional workmanship, straight to the point, down to earth and easy to understand.
I love your 3-section furnace. That makes crucible removal so much easier than what other people do.
God bless you sir, and the internet.
Thanks so much for posting this. I have wanted to build my own crucible for a while now and after seeing all the hard work you put into that beautiful crucible, I think I'll just buy one. Again thanks for posting.
This video was mad 8 years ago, has anyone tried it and please post links to any videos with improvements. Thank you good sir you will go down in history as one of the best backyard engineers. Always wondered how crucibles were made.
You sir are a true artist.
Thank you sir it is the best instruction I have seen on RUclips for this method
the sound of this alone is brilliant
I could listen to hours of peaceful relaxing workshop sounds
serious, love it :D
Happy New Year bud...... You are the man! I am so happy to see the dedication hard work and pride you have for your craft! I am a novice but learning and taking things slowly.... I was wanting to make my own crucibles just like yours so I am so happy to see it can be done! Cheers!
You did a fine job - respect!
brother you looked a little shaky at first, but you are the safest and one of the smartest casters on youtube period. i think your work is excellent, that same starbide crucible would cost 200 plus bucks..a spectacular job, i am very impressed, and i'm not easily impressed
kudos
Its all new to me the method you are using and there may be strong reasons why you do. However i come from a ceramics background where we were slip casting. That is getting all dry clay ingredients adding to barrel of water making thick slip clay, adding deflockulent.which makes it appear thinner, more wattery. Then we added slip to dry/ semi dry plaster of paris molds. The benefit is there is definitely a higher success rate/ failures due to cracking. Dont know of this helps but just what i know
I don't think I can properly express how valuable your video is, Sir. I have to try it on my own! From what I see, a meat grinder should come in handy for homogenizing the mix. If you ever test it, please post what the results are. Many thanks for your work, Sir! You're doing us a great favor!
The food channel has really improved.
All kidding aside this is amazing and inspirational.
I noticed when you were hand-mixing that you started kneading the stiff clay immediately after wetting it. When I want to "thin down" stiff clays a bit, I prefer to add the clay & a bit of water to an airtight container, then forget about it for a few days. Letting the water work its way into the clay on its own is far easier, and makes for a much less slimy experience, IMO.
thank you for the video sir, could you please put where you get your supplies from, thank you
Ingenious method. Thanks for sharing and providing a decent and highly informative video.
I wonder if you could use a hand crank meat grinder to break up the clay to make it easier to mix.
I'm been looking forever on how to make graphite!
Hi, glad to see someone else uses the wife's oven to make furnace parts. I also know what I can do with the 15 to 20 pounds of graphite powder I end up with after making molds every month.
Great video, I'll give it a try but on a smaller scale.... Nice job
The formulas and how to mix the clay was great. What you were doing after you made the rings was very obscure.
He was using a hydraulic jack to compress the rings with the collared steel tube he showed you in the beginning.
@rlbob1, did you score the ring segments before setting them in the mold?
He didnt show how the mold goes together, or how it is oriented in the press. It's not clear or detailed how he packed the clay nor did it show what keeps the clay from just pushing out the bottom. How did he end up with a solid bottom if he is using a hollow ram with a flange? No information on that. How thick is the walls and bottom? Not a clue. At 10:24 you mostly see his back not a clue what he is doing there. At 10:34 he ducks down so who knows what he is doing there. All the camera shows is the same large tube with a hex flange. Whats the large tube with the hex flange for? Between 10:24 and 11:21 he shows nothing of what he is doing. Between the beginning up to 7:40 its a great video. Between 7:40 and 11:21 not so much. After 11:21 he shows what is going on again. Like most things in life you never get the full story from one source.
Unfortunately the solid steel tubes did not allow much for camera angles so I had to rely on the storyboard in the beginning. Still I think I can answer most of your questions. The large tube with the hex flange is bolted to two 2*4's which straddle the concrete blocks and firmly hold the smaller tube and the core base in place. The large washer on the core base fits snugly against the end of the flared portion of the small tube and keeps the clay from pushing out the bottom. It also centers the core and forms a nice flair for the crucible top You recall the hollow ram also has a solid end as well as the washer end. After building the clay to the top of the core you flip it to the solid end and add another inch of clay for the solid bottom. The solid end is also used to force the crucible out of the mold after unbolting a board holding the core base in place. Just remembering it is being formed upside down with the flanged top facing down and the solid bottom up and that will help visualization.
Sorry I have been away so long. So many things happen in life which make filming RUclips videos seen trivial. I did make an experimental crucible but lost video and formula. Had the crucible professionally fired but owner of shop was so leery of it she fired up the whole kiln with just my crucible ... nothing else. Well in its raw unfired state it does like its made of gunpowder. Let me dig around a bit ... maybe i can retrieve it from old drive. Love you guys and gals.
bob
Glad to hear you are alive and kicking. I get the thing about things happening in life- death in the immediate family, new job, house burnt down in the forest fires, global pandemic… been there, done that, got the t-shirt.
Anyway, life does go on. I’m sure many people here would like to see your new formula. I’ll admit, I’m leery of putting glass (even powdered borosilicate) in my mix as I mainly melt cast iron and my experience with glass is that if any silica sand gets into the furnace it tends to melt into glass, making a sticky mess that can sometimes get between my plinth and crucible. Over the years, I’ve been through a few $$$grand’s worth of Morgan super salamanders and I’m getting tired of it. Asbury graphite isn’t too far from my shop and I can get bagged fireclay and grog locally too. I bought the Vince Gingery book on making crucibles many years ago as a curiosity and his formula, for a 3 pound mix (page 23) is “Hawthorne bond 35 fire clay, 38% or 18 ounces. (Or other fire clay may be substituted.)”, “Potash Feldspar 2%, or 3/4 ounce.”, “Brick grog 20 mesh 60% or 29 ounces.” He doesn’t say anything there about the graphite, but on page 21 he says “The graphite content of such crucibles is normally in the range of 30-40% or the total weight of the crucible”, so it could probably be scaled into the clay/grog mixture. He also says on page 7 “Typically a good clay was mixed with 20 to 40 percent of its weight of graphite” Those numbers seem pretty in line with yours. He mentions that of the amorphous and foliated/crystalline, the crystalline is the type used for crucibles and lubricants and the amorphous form is used for lead pencils, foundry facings, electric brush carbons, and paint pigments. I will probably give Asbury a call and see if one of their application specialists can recommend a particular product. I get the feeling from their website and elsewhere that they carry 50 or 60 different graphite products, varying in mesh, crystalline versus amorphous, and intended use. I got a 20 pound bag of powdered graphite from Budget Casting Supply years ago when they were still selling it (they’ve been ramping the business down for the last year or two, selling off inventory), but I don’t know what the intended purpose was. I’m using it as a mold wash for my gray iron castings to help it not melt and stick to the sand, which is a pain to clean. I don’t assume that just because it’s powdered graphite that it’s appropriate for crucible use.
Anyway, thanks for the video. Glad you’re back! Definitely please share your recent formula (with the obligatory disclaimers, if need be, though most of these jokers commenting are just arm chair warriors and won’t actually make a thing in their lives anyway). I’ll be doing some experimenting, but it feels like a waste of time to reinvent the wheel or duplicate effort that’s already been done by others before us. Thanks again.
Definitely coming back to this to craft my own crucible!
Would it be possible or beneficial to use aluminum oxide powder in the mix. Maybe a small amount. The reason im asking it is used to make the ceramic insulators on sparkplugs , and handles great temperatures . It is inside the combustion cgamber , and even seen the sparkplug electrodes melt, pistons melt. Have specks of piston splattered on the ceramic. And tge only thing i ever seen happen to the ceramic is a crack. Even seen people use the ceramic to spin form steel . Where the friction heats the steel allowing it to easily be shaped. Even welding it. So it seems the powder in with graphite could possibly help the graphite withstand temperature. Instead of the boracilicate . I had the idea that i may look into playing with some red clay used to make brick.. and mix it with graphite or carbon, possibly both. And look into possibly adding aluminum oxide. Use distilled water to prevent adding metals frim the chlorine corroding the pipes. Make a "mixer" by putting two wheels on a axel about 6-10" apart. With a gear reduction motor spinning it at up to 25-45 RPM. Tge wheels doing round in the bottom of a cut off 55 gallon barrel. With the bottom 1/3-1/4 bring used as the mixer. With a 1" piece of plywood bracing up the bottom. The wheels made from a chunk if hardwood tree trunk about 4" zo 6" thick and azleast 4"- 6" thick a pair of wheels from oak or something 6"-7" thick and turned down im a lathe to about 12" diameter. After spending the day imw oven at 250°f- 300°f, keeping an eye on it to see it doesn't get any darker than a tan use a lightly pressed and epoxied in steel sleeve in tge wheels . And another onto a 2"-3" axel made from a chunk cut diwn to 4" x 4" with a 1/4" steel plate bolted to the top and bottom with a
.375" keyed 1.5" steel shaft to spin the wheels , tge shaft being 12" longer than required to just spin The wheels and spindle. The shaft being roughly 16" long with a bearing block mounted center of the barrel with the shaft inside. making it look something like part of a clothes washing machine. The shaft below the bottom being about 6"- 8", (5"- 7" with the bearing block) then a roughly 60 tooth sprocket, then another bearing. Connected to a 2.5" bit of channel ,running from the leggs on the bottom of the barrel. Being about 14" long legs.the motor attachef to the inside of one leg, having a gear reduction to 250 RPM, (-/+), them s 10: tooth driving a 60 tooth (+/-) (maybe a 40 tooth) the wheel spindle being able to slide on the shaft , not spin. The steel inside the wheels having oilite bushings pressed on. Using a steel washer on the wheel. With a rubber washer then a large leather or treated paper or cloth washer to seal out dirt from the bushing. Zding a large C clip on w groove in the steel on the spindle. To retain the wheels. The shaft having a threaded hole with 1/2" bolt 1/2" deep. Used to retain the spindle uding a large 1/4" thick washer about 2.5" -3" dia. With a spring fitting around the shaft. Pushing down on the spindle with an adjustable pressure from about 10 lbs to about 50 lbs. The wherls capable of moving up and down about 10"-12" or so. The spindle having two 2 steel angle bars. Running out from the spindle to the barrels inside wall. Being about 1/8"-1/4" from it. It having a roughly 2"x 4" bit of rubber bolted to it. Possibly a piece of car tire sidewall. Used to gently rub the inside wall scraping any material off it. Putting it under the wheels. And possibly have wheels or rollers to attach to the bars, rollers bring they wound be about 2.5" dia. Abd 4" tall. However the scrappers will likely do best. With a large PVC coupling under the spindle shaft to keep material away from the shaft. The speed of 45-60 rpm max. slowly add matereals and a fine mist of water. To jeep it dry as possible. Possibly the best speed would be 10-15 RPM . Euth a speed controller. To set the speed. And seal the wood parts and wood wheels with a clear epoxy, thinned to allow it to be absorbed into the wood about 1/8" of the outeside , dependibg on type and density. Then apply a thicker coat to the outside for a tough exterior that should not rot. Being hot dried. Tfe thinned epoxy could completely soak in. Especially if a pressure /vacuum chamber is used. Remove all air from the wood replacing it with epoxy. Completely stabilizing the wood . Making it a composite material. The wheels being 1/2" smaller on one side than the other. With them being mounted oppositely , pushing the material back and forth as they roll over it. With a lid from the barrel to prevent dust. And it should nearly be a professional pos, uh um, poe, piece of equipment!
😅 ✌️... then make a furnace from the rest of the barrel and another. Having 3 , 7' bits if 1.25" -1.5" even 2" pipe, with them connected at the top by 2" angle steel, 1/16-1/8" thick, the bottom doing the same by forming a 36" x 36" or 42" x 42" square. The pipe welded at the corners. A bit of 1/16" sheet steel welded to the inside bottom square. Fill it with concrete. Possibly add a 1" x 6" board to the outside of the angle, then fill eith 6" of concrete
Locking wheels can be used under the steel frame. Then a barrel bit
6" - 8" thick placed on the center of the concrete pad a piece of rock wool or other insulation that is solid , and handle higher temps inside the barrel then pour about 4" of refractory mortar inside the top of the barrel. Mount a hand crank winch to the pipes to a bit angle bolted or welded to two pipes, and a bitbof 2.5" channel steel crossing the top. To mount a pulley to tge center of the square. (Use a hand crank winch or a small electric winch as long as it moves the cable fast. Then cut a hole about 6" im the center of the bottom of a barrel. Use about 3/4 of a barrel. Then cut both ends from another barrel naking it the same length. (Or buy a piece of 18-20 gauge sheet metal . Roll it into a tube smaller than the barrel. Leaving about 5"- 6" on each side of the tube. Drill several holes in the barrel 1/4" use all thread aka threaded rod. To go between the barrel and tubei 6places. Then at least 3 holed in the bottom of the barrel then drill three, 1/2" holes evenly spaced near the outer edge. Install 3, 1/2" eye bolts , with a 1/4" rebar welded to the threaded shank. 18" long, eith a fender washer welded to the end of the rebar after the Eyebolts bare installed! And optionally, bend a bit of rebar into a ring about 4"-6" saller than the barrel. Weld it to the fender washers.
Then mix refractory mortar with saw dust, about 5 lbs of saw dust and fill the gap with it. Between the barrel and tube with it. When it's set, fill the inside of the tube with extreme temperature wool wool used in furnaces, to handle 2°-3°k f. Used in assay ovens and such. A 1" single layer should work. Then flip it over attach chaind 12" long to the eyebolts. To a single centered point. To be lifted by the winch. Lift it and sit it on the insulated portion of the pad it should weigh about 40lbs. Drill a 2" hole in the top for a 1.75"- 2" pipe , with it capped in the bottom ofvthe barrel then drill three 1" holes about 4" from Beach other the bottom/end pipe 2"-3" long welded in the larger pipe aimed up at about 15° up 4" at the next pipe it's 90° from the pipe all also aimed about 45° from center of barrel. Then moving up about 6" welding on the next 1" pipe , aimed down at about 10° . With a 1/4" steel tubing running inside the larger pipe having 3 outlets. The with a cap threaded on to get a roughly .060" nozzle in each. And possibly add another pipe with more nozzles. With with another gate valve to adjust fuel. And connect a electric leaf blower by flex hose to the 2";pipe. Having a 6" Radiused 90° elbow at the top. And a 12" pipe with 3" barb to clamp a hose to the pipe. . Capable of spraying propane through the nozzles that are inside the 1" pipe just as it opens up in the larger pipe.. the fuel having a fan spray pattern. With a single trio of nozzles capable of a 20:lb propane bottle in about 8hrs. on med. And possibly use the secondary nozzles to spray used oil. And crank up the air flow. And btu !🦾.. possibly exceed 3°k F and add a barb fitting to connect a o2 hose. To get possibly 45% o2 in the air flow! to = 🔥 HOT possibly overheat the insulation. The furnace lifts off the crucible. Making it easy to lift. Then the heat stays inside the furnace. Just close the top vent. The hot air stays inside. lift off the furnace from the crucible
Making the reloading easy.. dirty to ramble have an awesome day🎉!
Fantastic safety measures with the fire suit!
thank you sir, i will pass on what you have shown me to my students
Very good video. Very informative. Thank you for the detailed information you provide with the formula.
What is the temperature needed to dry and cook a graphite crucible?
Crucibles that you can buy have a kind of glaze finish, what would this be?
I'm looking to make a crucible to melt more-or-less pure quartz (silica). It melts around 1700°C. A pure graphite crucible melts around 3600°C so I think that'd work. But...do you have any idea if your graphite crucible mix could work up to around 1900° (I'd like a little temperature buffer to work with since I might have to run at 1800°C or so). I suspect since glass is a component in your mix it will cause your crucible to fail when the borosilicate melts, which is apparently 1648°C...although sometimes mixes have surprisingly different properties so maybe it could withstand higher temps? Have you ever tested it?
Well thought through and presented and a rather unique subject. All thumbs up!
Respect on your work sir
Some of you have not seen D he touches blocks of just set blocks of aluminum with almost bare hands it nuts how you people endanger your lives. Thank you Loader.
has anyone made one of these crucibles? if so what metals have you melted?
brilliant work dood! im currently into induction melting and making graphite crucibles is of huge interest. cheers fella
Really nice looking crucible.
Safety at all times cuts to clip of him handling molten metal on a wooden porch covered in leafs lmao love it
What do you figure cost and all materials to make (just crucible) and what size is it in holding volume you would say?
I like your ingenuity. I don't feel alone. Essayons
This was a very well presented diy.
I noticed you don't reply to most questions. But here goes
Can that mixture be used for molds?
Would having the clay in powder form be a good idea?
And a question I see asked is will this work to melt steel??
Thank you for your time and effort in sharing this video. It's the only one I have seen for making clay crucible. Thanks again and have a great day kind sir!!!
From everything I've read trying to find a source for a crucible w/ which to remelt some steel, any graphite crucible will just leach carbon into your steel and you'll end up w/ cast iron & a (severely?) compromised crucible. Any attempt to melt iron or steel has to deal with a couple of issues: protecting the melt from oxygen in the air [since the kindling temp of steel is below the melting point] (which is apparently normally accomplished by a layer of molten glass on top of the melt) and a bottom-pour capability (because the protective glass layer would form inclusions & other flaws if you tried pouring from the top.) I figure one of the small inductive furnaces sold for Al, Cu, Ag, Au melting would be fine, if one used a bell jar approach to evacuate most of the atmosphere & then introduced argon [widely & cheaply available from welding supplies;] the minimal surface exposure from the deep, small diameter crucibles those units require would enable one to pour a casting w/o compromising the batch, but nobody seems to offer a suitable crucible, just the graphite variety. Probably because of liability concerns... pesky injury lawyers! 🙄
I would also definitely purchase one if you sold them. Great video!
Please let me know if I can purchase one from you.
I am a bit familiar with ceramic slurry casting. as that is for dishes, cups, and decorative items I know that such clay would be a poor idea for a crucible. that's not what I was thinking though. for those who aren't familiar with it, its simply pouring liquefied clay into a mould and keeping it full for a certain amount of time. that is where my question comes in: can you add enough water to make the graphite clay into a thick slurry and cast it in much the same way with at least a reasonable success rate?
I was going to ask the same question. Did you ever figure out the answer?
+Jacob Lanctot not at this time. not in a situation where I would be able to try it myself.
has anyone tried to make the clay mix into a thick slurry and cast a crucible that way yet?
finished product looking good.
been thinking about having a reasonably tall kiln and cruisible combo where i can put in a complete cilinderhead (unbroken with valves springs everything still in it )
i seen it done once but the guy used a verry large burner putting the flame staight in the opening against the aluminium inside a steel barrel layed down at an angle with the catchcan under a hole in the lowest point , verry crude and wastefull in the amount of energy used to melt it but it worked
the dross basicly stuck to the barrels wall on the way down while the pure aluminium dropped further and out the hole
like to try it with the kiln vertical and the burner as is normally placed and have a hole in the bottom of the cruisible sitting on a hole in the bottom of the kiln , the kiln sits higher off the ground then usual and the mould is placed under it (want to make clean aluminium ingots that can be remelted and cast the normal way )
my thought is basicly to not spend a lot of time pouring or even take out and handling a red hot crusible , taking out dross and all that but just have the aluminium leak out the bottom at the same speed as it melts off the head
and keep adding scrap through a hole in the top and having moulten aluminium pour out the bottom
any idea how to get the dross to seperate while the aluminium drops out ?
will it stay in the crusible or block the pourhole ?
if the dross comes with the aluminium leaking out i was thinking on a small gutter from the leakpoint down to the mould for the dross to stick to , but it might be too cold and have the aluminium solidfy before it enters the mould or just make a bigger mess of things
would it have worked better to mix the three powders together, add water and then kneed in the clay?
Very nice job. Don't feel like it was too long. I would liken it to watching Julia Childs. Where most cooking shows give you a whiz-bang kind of presentation, hers really walked you through step-by-step.
Incidentally, in some recent research I did find someone mentioning to glaze the crucible with silicon carbide powder. I cannot really comment on its effectiveness, because I haven't tried it yet.
This is great! Very informative and nicely done.
I'm looking into casting metals, starting with aluminum, and I wanted to get clean non-ferrous pours to maintain the strength of the alloy for use in machine tooling. I did a search for fire clay and the closest I could find was "low-fire clay". Is that the same stuff?
Also, I was thinking while I watched your very informative video that adding even a slight taper to your forms would make it easier to extract them after pressing. Has anyone tried this?
I am using a ready mixed ceramic clay called "woodfire" in the video. Clays of this type are available at ceramic shops for making pottery. Try to find a clay that fires at the highest Cone they have available. Google "ceramic cone fire chart" for more info. Other options are of course steel crucibles, stainless,ceramic clay, etc. Steel does not last long due to the corrosive nature of propane. Stainless would be great but it requires Tri-mix shielding gas and stainless wire to weld with a MIG. Very expensive. Clay as I described is cheaper than steel and will last longer.
You could make a crucible mold out wood divide it into 3 or more sections bolted together and ram it by hand. The core is a problem when you start making one any larger than a drinking cup or glass. It sticks fiercely to wet clay due to the suction of the vacuum created trying to remove it. Hard as it is to imagine this effect is so great even a heavy bulldozer can get stuck with the right mix of clay, mud and the vacuum effect.
bob
Thank you for the information bob, I appreciate it.
did you find that your formulas is ok or did you come up with a better one .
wow, your pretty smart. I didn't think it would work. Thanx for help.
Silicon carbide can be obtained from ceramic insulators used in various applications where nicd coils are used? Borosilicated glass can be obtained from pyrex glass? Graphite can be obtained from the back of old style tv tubes and computer cords? Are all these assuptions correct and fire clay is there a free place to get that?
Ah thank you for making this i always wanted to make my own graphite crucible
thanks for the information, I would really appreciate if I see a video of the new formula
Can we make Borosilicate glass powder????? Not able to find here or is it just glass powder???? pls clarify
would you like to share composition of different ingredients you used to make graphite crucible
can you buy a dry fireclay and then dry mix and then add water then mix with a kitchen aid type bread mixer using a dough hook??
I'm a amateur mechanic. I really like the foundry work, melting metal. I have a lot of car parts anything from aluminum heads, to steel leaf springs. I figured instead off tossing them why not melt them into other things. Use the old things to make New things. Aluminum heads no problem melting. 1095 steel coils very different animal. I figured if I can melt steel then everything else would be easier. Thanks cont.
Where are you getting the borasilicate glass?
Beautiful piece of work!
What formula would be needed for the silicon carbide crucible? Substitute the graphite for the carbide and use three ingredients, with a high grade fire clay I surmise...
The chair he is sitting in LOL
Informative video.
i did it, there were too many cracks, I wonder why?i would be glad if you answer
Now, how to make one w/o any graphite that would be suitable for cast iron/steel? 🙂🙂
While it’s been over seven years ago and prices changed and product availability may have gotten more complicated (or not), I’m curious as to what it cost to make and about what volume does this one shown hold. My small-ish (A5?) was about $35 if I remember correctly (I probably don’t).
I love that fricking suit dude.. .can I rent it for Halloween? lol Great video... I am going to use some of your procedures, and tweek others to fit my taste. :)
Hi, do you have a list of the material sources ? Where would you purchase the material. Please be specific. Thanks John
good job you had a robot to help you at the end:)
is there any possible way i could order a custom one from you?
YA i would like to know as well
Me too.
me too
R2D2
Is there any particular grit size you are using for the silicon carbide? I have some 150 grit and some 1200 grit any benefits to one grit over another?
Where did you get the borosilicate glass powder?
thanks for your video,yesterday i made research on the net and found out about lost foam casting and slury for better surface."The prepared foam patterns were then dipped for 60 sec. into a slurry made of a mixture of Zircon flour and colloidal silicate".You can find out some more if you Google article;Process Control of Lost Foam Casting using Slurry Viscosity and Dipping Time
The crucible can be enhanced with a sacrificial coating, painting on a well mixed slurry of plaster sodium-silicate and graphite every few times you use it. Just to give them a longer service life, since it does take a bit of time and money to make them.
One tip on clay: it resists water absorption if it already has any water in it, so you could pre-weigh it for your formula, then let it dry completely out. Completely dry clay absorbs water very readily and it's easy to make into a paste. By the way, what kind of metal are these crucibles for?
Dude awesome AWESOME video. Thank you so much for the exact recipe to make my own. I know it could get spendy buying them. Glad you taught us how to save money. I do assume we can save clay for later if we do want to make smaller ones?? or should i just cut the recipe in half?? just lil curious because i dont want to use a large one all the time.. Once again GREAT job on the video. Makes it easy for some ppl like me to follow along.
Thank you for sharing it! Great work!
what size is the dimensional size of the crucible and what is the amount it holds , I won't be working with large amounts and wonder if it will be worth the effort and cost to make this
This gave me some ideas on what I need to do, I want to make a crucible that will accommodate the irregular shape of my furnace and not waste any space but concerned about the heat flow as well. I don't want to break down its efficiency so any suggestions would be appreciated as for the fire chamber coverage
NICE!! Where can I get myself one of those cool spaceman suits?? Thanks
At the time sold on Ebay as used Military surplus. Called a proximity suit used by Navy aboard ships. Probably all gone now. Pants and coat were cheaper than jeans at the mall.
Nope they still use them
Have you ever tried this with a standard Kaolin based clay??
ive found if you roll out your clay real thin, sun dry it and then crush and powder it. you can mix all the dry ingredients like a cake then add just enough water to make a air free mold. pack it and is way less work to get a extremely even blend
altazink Good idea. Still it would be better to use some type of motorized device to crush it. Maybe a large steel roller filled with lead on a motorized turntable. That could also be used to crush the glass from scrap Pyrex but be sure to make a cover for it. Glass as you know pops many feet when it breaks.
+rlbob1
Ball mill.
2nd the ball mill. It also seems extremely helpful for mixing green sand. I found an old steel hollow ball. I believe it was a tank float? Figured full of lead it should weigh 30 pounds or so. Should be plenty of weight to press the ingredients together. Far as i know anyway.
Please sir what was the temperature you used to fire the graphite pot
Hi Bob, so 2 things I'm curious about. 1- you spoke of a new formula you had a few years ago. Has that worked better for you and would you care to share? 2- with these crucibles, once you do the slow process of bringing things up to temp for your first pour; do successive pours have to be slow as well? In other words my crucible is setting around for 2 weeks. Do I need to heat it up really slowly when I decide to do some casting or can I just ramp up my foundry furnace on waste oil like I normally do with a steel crucible?
@rlbob1 absolutely genius of our time, I do have a question, what would be the cons of have a stainless steel reinforcement in the mixture, similar to the technique of reinforcing concrete, seeing as stainless steel melts at a temperature far greater than what a home foundry could ever produce?
Is it possible to cast graphite or anthracite coal like a person would cast metals? like heating and pouring into a mold?
are you a traveling man
Follow up on the glass question do you have any suggestion on a supplier for the glass
is it critical if i dont use de silicon carbide? i have all the other materials but i cant find the silicon carbide in powder form
Have you tried mixing the ingredients as powder? As far as I can see in the video everything except the clay is dry. I would cut the clay in thin slices, let it dry for a couple of days and break it to small pieces. Once everything is mixed properly, add the water.
I'm interested in your technique. I CNC engrave graphite Metal moulds and end up with a lot of plumbago graphite powder and want to recycle it in a graphite ceramic with clay and sand for spin casting moulds. But my attempts to make my own water glass -Sodium Silicate from sand with Lye -Caustic Soda) as part of the Mixture got me into a caustic mess. I have Neutralised and am washing out .
You might want to try Ins-Tuff Ceramic Blanket Rigidizer. Be aware it is highly hygroscopic and takes a while to dry. If you have scraps of ceramic blanket you can also experiment with milling and screening to a powder to strengthen the graphite/clay mixture.
I know the video is 6 years old, but if you see this I would love to know how do you clean the residue metal out from the crucible? Or do you use one for each metal?
One for each metal. Never leave any metal in a crucible. Dump on ground if necessary. Residual as long as no button left in bottom will dross in next heat. Otherwise it will crack crucible.
What type of metal are you pouring at the end of the video?
Trying to melt approx. 56 pounds of steel. I have 55 gallon drum, 2 in. 3000° refractory all around , 2 in. 2600° ceramic blanket. Not assembled yet. Any advice greatly appreciated.
WOW goooooood nice Man >thank for you and Your kind assistant
awesome video. great crucible. I want one as big as this. one question though, how expensive was this to make?