I don't know your age but I think you are very young. You make me happy knowing there are young people out there that are interested in accomplishing something. I am a 54 year old machinist that had a father who was many things including a foundry man. I can't tell you how many times I kick myself for not asking him how to cast metal. Keep up the good work. You are an asset to your community and the world at large.
+Grady Bledsoe I just turned 20! Thank you! I will keep it up! I want to become a mechanical engineer I think! Not 100% sure yet. I've always thought machinists were awesome!
I like that you put your failed attempts on the videos. there is nothing worse than watching polished videos. I like the learning process you go through. Cheers mate.
Hi Makerj If you want to cast thin pieces, you have to heat your mold (sand/plaster mix) and then pour your metal.This will give the metal a chance to fill the cavity before it gets cooled by the wall of the mold. We have previously discussed this. I regularly cast 0.3mm ( 0.0118110236 inches) wall thicknesses using this technique/principal. Keep up the good work...it's impressive how far you have gotten through your own efforts.
electro1622 I will hopefully be trying using plaster casting soon. I bought some plaster recently and really want to try lost wax or lost styrofoam. I just need to get around to doing it! Thank you!
2 things: First, your sand needs a wetting agent. Something like gummy, used motor oil or heavy silicone oil works well for sand casting aluminum. If you do that, the sand won't fall out of the packed cup as easily (no more tape) and it will pick up fine detail better. You can use other chemicals, but do not use something that attracts moisture as that can make the sand casting dangerous. I like heavy automotive greases but you can mix ingredients a bit. There's a number of lithium greases that would probably work well for this. Second, your aluminum is seizing. You need to heat the mold.. Heating the mold prevents the aluminum from losing heat as rapidly, allowing it to flow as a liquid for a longer period of time. Even bulky pours can seize if there's a narrow gap between large volumes. Sand that can be packed tightly and hold's it's shape during heating allows the mold to be pre-heated which slows the rate of cooling during a pour and decreases the likely-hood of the aluminum seizing in an odd place.
Cast the cup from the bottom up. The other way up from the way you are casting now. ( Also no problem filling the cup with sand) Your sprue goes down the side to the bottom. add straws to the top of the cup to allow it to vent out of the sand. At the moment you have no way for the gasses to escape and be replaced by the metal. Regards, Matthew
Absoutely classic engineering science. Finding what does and does not work in this way is what has led to the greatest inventions. Voted. [I'd give this guy a job any day. He has a good engineering mind]
I used to pour flowers and insects out of steel alloy back in the day. I never used sand because it's not holding well. I used to pour plaster around them on a vibrating table so all the air gets out. Before pouring the metal, the form was heated in an oven. Then, I used to melt the metal right in the mould, using a oxygen flame. Then we would spin the mood in a manual centrifugal machine. The pour was perfect every time, details like the hair on the spider's legs was visible while using quality dental chrome vanadium alloy. So your problem is the mould and the feeding. Use thinner sand or plaster to increase the detail. Make the feeding rod smaller with a cooling reservoir on it, (usually a bump close to the object). Most of all, heat the mould up as close as you can to the melted metal temperature. Your mould is so cold that it cools off the metal, that is why your pour is not complete... Let me know if you need more hints like the DIY centrifugal machine. Cheers!
Just a tip. Cover the polystyrene with a coating of dry wall plaster. Mix with water to a slurry and paint on, or spray the cup with water and dust plaster over to get a thin coating. Let dry completely. This will prevent the dry sand from collapsing into the mold as the polystyrene is vaporized. Cheers Cam.
Interesting experiment. I did the same thing with the foam cups back in 1969, when lost foam castings was just getting started. If you want to use some really good sand that is easy to get on ebay, buy a bag of Petrobond. You won't have to mess with water because it has a binder that won't evaporate. Petrobond will provide many good molding opportunities for you, and lasts forever. Keep up the experiments. It's great to see an inquisitive mind fooling around with foundry methods.
Good video - as you can see from the comments a finer end product will mainly be the result from using finer packing materials (find sand, pulverized kitty litter etc..) but what's great about your process is it teaches the beginner the process and by doing it this way and then changing a little here and there you really develop an understanding of how it works and how to perfect it. - cheers!
Thank you for including your failures as well as your successes. Too many of these videos gloss over the trial and error part of figuring this stuff out. Great stuff. =)
Makerj101 i think its the sand your using that is causing the issues, as the foam is being burnt away the sand is collapsing into the cavity before the aluminum can cet there, look at getting propper casting sand or green sand as its called. you can also make it, loads of vids on youtube for you to learn how to make it
chaos Regular play sand is fine for lost foam. Green sand doesn't work weel because you can't pack it properly. He could try a plaster shell. I think the type of foam isn't right. Ilso his set up needs some work.
The proper way to do it is to make a clay slurry. Then paint that slurry onto the polystyrene (all over except pouring hole) and let dry before you cast. This not only holds the model together when it is to be cast, but also keeps all the detail too.
Not sure if you found out yet but your problem is the sand. you need a sand that will hold some water so its sticks to it self and hold shape better. look up videos on green sand or how to make green sand
+yoududeuser yeah ok that's why there are like 1000 CZcams videos of exactly what I'm talking about. Instead of being a moron why don't you look up the videos that already show people doing exactly what I'm saying.
+yoududeuser Because you're being a moron, spewing false information and potentially scaring some people. A good saying you should follow: If you don't know what you're talking about, keep it to yourself.
+yoududeuser Seriously, dude - you contradict his solid advice screaming, "NO!" - so he is justifiably compelled to scream over YOU. Then you go and get all butt-hurt. Ridiculous. He did not owe you that apology, so don't go thinking you deserved/earned it.
+AGENT CHAOS Naaaaah, that's bullshit. You end up with a shit ton of steam in your cast, ruins surface quality. I tired it, was aweful, upgrading to real casting sand shortly.
hey man. i just had some thoughts from my own personal experience on how to cast whatever you want quite easily. I do some lost foam casting and normal flask castings, but i use greensand for both. The advantage of green sand is its a bunch of sand particles coated in bentonite clay. It holds whatever shape you mold it to quite well. you can basically take a normal object of any material, make a mold of it with that sand, and its holds the shape for the metal while it's poured in. but the reason i suggest it is because it looks like as the foam burns out your sand shifts and cuts it off. if you used green sand it wouldnt move and it would just cast the object you're after quite accurately. I went to petco and bought some natural terrarium sand for reptiles. mostly because its super fine sand, and its already filtered for any larger rocks and such. a 10 lb bag is 15 bucks. then i mixed that with a 1 lb bag of bentonite clay. which i purchased for about 5 or 6 dollars off of ebay. the trick is to mix the two together really well dry, then slowly use a spray bottle to add water and keep mixing, just until you can squeeze it and it holds it shape without crumbling super easy. you want clean breaks. keep it in a sealed container. don't let it dry out. and after each use i take all the hard dry bits and break them back up and mix them back into the sand and add more water if necessary. you can re-use it hundreds of times. hope this helps :D
This is great! I actually enjoyed seeing you learning from the early casting, because I think it will help me avoid those mistakes. Great job, and keep on making!
On thin sections the foam outgases then the sand collapses before the metal can fill the void. Two things you could try -- 1) make a very thin slurry of plaster of paris and paint it on. Once you get the thickness you need bake it dry. NOOO wet plaster! Then follow your normal LFC methods. 2) Find a high temp paint that you can coat the foam cast with. You will have to experiment here, many paints have esters that eat the foam, some don't. Once coated follow your LFC methods. This provides a skin to resist the void collapse so the metal can fill the void. Good vid.
Mike Studmuffin Yeah it totally could. But as long as you don't use much water it's fine. Green sand has water in it(except the oil based stuff). But it's only like 3% water or something. At those amounts the steam can escape fast enough through the sand. A volcano of molten aluminium would not be fun hahaha
Makerj101 If you are looking for bentonite, I would see if there are any small well drilling companies around your area. They use Bentonite clay powder that is so fine it's amazing. Its used as a drilling lubricant. That way you don't have to fiddle around trying to grind kitty litter to a powder. In a lot of cases, you can tell them what you are doing and they might even give you a little in exchange for showing them what it will be used for. Also, I think farmers Co-ops will sometimes have it, used for various things like sealing the bottom of fish ponds and such. Thanks for sharing
Maybe use water to pack the sand but then let the pot dry out in the sun for a day, I'd say cook it but it could melt the styrofoam. Blow dryer in a cardboard box?
Good job. Its nice to see someone as young as you taking an interest in doing things like this. If you ever go to Pick-N-Pull auto salvage, look at the aluminum cylinder head castings and you will see nice clean imprints of styrofoam forms.
The casting (green sand) idea many are propounding here is what you need, but be very careful with what you pour and wear at least boots and a face shield when you do it. You will need exhaust vents too as this gets really dangerous if you have an area of sand that is surrounded on all or most sides (as in the case of a downward facing cup) by molten aluminum. You'll get superheated steam in an instant (from the moisture in the greensand) and, if it has nowhere to vent, it will cause a small explosion in the molten aluminum by trying to escape through it, potentially showering you with the hot aluminum. Anyway, it's wonderful to see a young person interested in interesting things rather than pursuing nonsense. Keep up the good work and keep experimenting and it will pay big dividends later.
You did a good job with your early attempts! Cope, drag, sprew, riser, gates, are all terms you need to know a little more about. Green sand is a combination of clay, sand and water. It is has been awhile since I took my foundry class in college but I will tell you there is already some good information in the comments down below. I don't remember any oil used for any castings in my foundry class. I had also forgotten about parting dust until a friend reminded me when we were pouring stuff in his back yard foundry. A good parting dust for a home foundry is baby powder.
You need to use green sand. The metal is more dense than the sand you're using and it is pushing the sand out of the way which is affecting your detail and resulting in the incomplete molds. You also need to compact the sand in layers around the mold as tightly as possible. Make or buy some green sand and you will notice a world of difference.
your video quality is great and you're very informative. stick with it man because watching you try and learn how to do it is even more entertaining and educational than most videos on similar topics. start a gofundme for your videos! it's worth a try!
Nice vid thanks. Like other people said green sand would help. Or an alternative is to paint on a thin layer of plaster, over the foam. It takes time as the plaster has to be well dry before you pour, but hat will stop the dry sand collapsing in and spoiling the casting.
I'm pretty sure part of the issue here is with the type of styrofoam you used. Some styrofoam is very light, while some is denser. Styrofoam cups (and plates and bowls) are made of slightly denser styrofoam, and some of them have a slightly plasticized surface to prevent leakage. So, rather than instantly vaporizing, they melt, producing a barrier to the clean flow of aluminium. I have cast some very thin styrofoam sheets successfully when I used expanded polystyrene insulation that I cut into thin sheets myself, rather than using pre-made thin products such as plates and cups.
you'd have better luck if you used something to dampen the sand...either a finer grade greensand using water, or an oilsand so it can be compacted and will retain it's shape better find an old metal shop text book and study up on some of the methodology (or check on line, there's lots of good resources; just google "lost foam sand casting" casting using lost foam is very workable and allows for complicated detail that is otherwise impossible in an ordinary cope/drag format. But you need something to stabilize the sand while the foam is melting away. One site I know of on CZcams, he coats the foam in wallboard mud, gives it a couple days to dry hard, then fills in around it with sand. Such a method can give truly impressive results....
wd40 seems to work well for firming up the sand. Makerj, your sand is caving into your mold as the foam melts faster than the metal can flow. it doesn't take much to hold the sand for a split second longer and improves pours dramatically.
I found this really fascinating. As already mentioned by others, I suggest you have some exit vents to aid the flow as well as the entry point. This will be even more important once you start wetting the sand as I think right now most of your air is escaping through the dry sand. I'm looking forward to watching more of these vids as you progress along your road to discovery. Makes me want to have a go!
Some suggestions: Try manufactured sand. It has sharp, angular particles that interlock and cling together. Make a wooden frame, place it on a board and put the polystyrene cup inside, right-side-up. Then fill it and surround it with 'green' sand. (slightly moistened sand.) Inverted the whole assembly sharply onto a flat surface. (concrete or granite should be okay.) The base of the cup should now be on top and that is where you pour.
Maybe I'm wrong, but I think that aluminium heatsinks are made in bulk by machining solid blocks of aluminium, because not even with perfect sand (or plaster or ceramic) casting can you get heatsinks as perfect as when you machine it. That's why the compressor blades of the turbochargers are made by machining too.
Take kitty litter and pulverize it the consistence of talcum powder. mix it with fine plaster sand. Your sand needs to be moist but not too wet. About like what you would need to make a sand castle. Put foam in sand and tamp it. you will get good results.
+Jeff Stone LOL I just posted a video about this a couple of hours ago! czcams.com/video/DCYUgq-Awfg/video.html&lc=z12jjphojui0hzk0u22uvrdqrm2tgljrn04 Thank you!
Plaster is not that expensive and it provides better insulation as to not let your aluminum loose as much heat so you can get much thinner casts! You can also crank the heat up waaaaay more. If you cast the Styrofoam inside the plaster I don't see why you couldn't get much better pours! Just make sure to get all those air bubbles out Another idea would be to cast the Styrofoam inside the plaster and burn it away inside of your furnace! This would also allow for all of the moisture to be removed from the plaster. If you do a 50/50 sand and plaster mix you could also play around with making some reusable molds but it'd take a little bit more planning and possibly some more failures! Let me know what you think!
You need to make channels coming off the bottom of the cups so that the air can escape. The molten metal is getting air trapped and hardening before the metal can make it all the way to the bottom.
Hey young man do some research on making green casting sand I think its hot enough but the sand is closing in on the foam that is why the double cup method worked better. good hobby keep it up.
Use 2 X 4's or 2 X6's to make a good drag (the bottom part of your two part system), use the same thing to make a cope. Fill the bottom with your green sand (clay water and sand combination) set the cup full of moist, not wet sand (packed as tight as you can without breaking the cup) on the bottom half of the mold you cold cut Q-tips in half to make a fair number of gates running off the top, which is now the setting on the bottom half of the mold. Set the top half of the mold on top of the bottom half and use a regular number two pencil to make a riser. Fill the top half of the mold with more green sand. Once it is all packed into place you should be able to separate the top and bottom half of the mold you can then cut a runner to the riser into the bottom half of the mold. You can also remove the Q-tips. The gates will provide extra heat down at the bottom for the thicker part of the cup. Use something round to make the sprew and make it conical near where you are going to pour it in. With green sand you should be able to remove the thing you used to make the sprew, just like you can remove the number two pencil before you pour. The only thing you are trying to melt away is the foam cup. I was not able to read all 495 comments, but you sure got a lot of peoples attention if you got that many comments. Good job.
Myfordboy on youtube uses washing soda to degas his aluminum. Also recommends only using previously cast aluminum rather than extruded or tin cans. I'm impressed with what you are doing. Thanks for sharing.
Great work! You've got the right idea...always look at the outcome and ask yourself " is this what I expected".If the answer is "no" then formulate more questions! Be careful of using water and sand when casting molten metal!! Green sand must be proportioned very carefully!! Too much water and the molten metal will cause the water to instantly vaporize and potentially cause an explosion (just watch some of the videos of folks melting aluminum pop cans). Keep experimenting.... Here's a hint... It looks like most of your metal is solidifying in the sprue! What about positioning the heat sink foam molds horizontally in the sand and feeding the metal through several sprues (a manifold) to distribute the molten aluminum more effectively.
i honestly dont know much about aluminum casting, but it looks like you are using regular sand as opposed to the red sand meant for casting, which feels more like clay than sand. if that is the case, the problems you are facing may be due to the sand collapsing in on itself as the styrofoam burns faster than the aluminum can flow in. but that is just a guess, based on being a mechanical engineer, and not being an expert on casting or anything
Oil the sand a bit and ram it into the mold. You'll have to work out a sequence to keep the styrofoam from collapsing. Also consider making a core from the inside of the cup and then fitting a negative of the outside of the cup over it. The thin styrofoam seems to be able to keep the aluminum out of the cavity by gas pressure or cooling of the metal.
You should use "green sand" dampened to do deep foam and fine casting. Plaster of Paris is the norm though. You can get a better copy of finer objects if you use the plaster method and not have as much rough texture. Also to make small things like jewelry, shims, pins, etc. you maybe should cast them in a flat down position, take you damp sand and carve out the designs and pour them. after they cool hit them with a bench grinder carefully with a fine wheel to trim them up and smooth them out. Again you can plaster cast them too. Not in the sake of saving power and time you can try the DIY arc furnace method by using carbon rods, fire brick and an MOT. This will eliminate the need for a crucible as you can bore the brick out and even give it a pour spout. There are youtube videos on how to build one cheap using MOTs. An arc furnace can get hot enough to melt aluminum and even steel in a very short time. I am designing one myself to have for when I need a special custom bracket, or spacer or whatever made from steel, copper, brass, etc. Seems like a useful thing to have in the shop.
ElfNet Gaming I am going to try to find some bentonite clay kitty litter to make some green sand. I also really want to try lost wax casting using plaster. I bought some recently so hopefully I'll get around to it soon! Yeah Grant Thomson! I've seen those mini arc furnaces and they are awesome! I have some nice big carbon rods too! :D But they are kinda antique so I'm not sure I want to use them...
Hey, I actually think the pouring went wrong because the sand collapses under it's own weight. The bottoms of the cup melt and the sand just sags down in. This might well be the reason of the fails. You could use denser sand types that come pre-mixed with a type of oil to preserve shapes inside.
To be more precise the foam is not all really being melted by coming into contact with the metal. It is burning from the heat that precedes the metal so that the sand collapses. I agree that wet sand or some other sand will hold its shape longer as the foam burns out.
I use casting sand, and when I am about to start the mold, I use baby powder and brush it on the original... then when I use the casting sand, I pack it in... use some method of vents, similar to the straws you used. hope these tips help you out. make sure the casting sand is NOT dry... has to stick to itself. have fun!
If I can suggest using wet sand as it will be more structural when the foam is melting away. In your heat sink the sand is filling in faster than the molten aluminum after the foam melts. Good luck
Your problem, in regards to casting the cups, is that you're using 1 large sprue leading to the thin bottom of the cup and expecting that you don't have so much heat loss that it allows the molten metal to travel all the way (again, along thin walls, exposed to lots of cooling sand) to the lip of the cup.... You need more channels, leading to the outer edges of the cup bottom, from the main sprue, which will allows more heat retention... You should also heat your metal WELL ABOVE the actual melting point (at least several hundred degrees fahrenheit) so that as the metal cools it doesn't solidify immediately upon contact with the sand.
yeah i think the problem your having is the sand its too loose and instead of the gasses venting out the pour hole or vent holes they are out gassing form the whole mold so your getting a rough cast.
the commercial casters dip the Styrofoam in a slurry of alumina powder , you may try plaster of paris to give it a coat of light skin , let it dry and you got a perfect cast.
Wow, nice video! That cup is awesome! Maybe if you just try it another time it will be perfect. You could sand down a little bit of the top part and keep it on the stand, then polish it, would be nice :) Nice experiments, gives me some inspiration for when I start again with casting, when I have time, and the weather is good at the same time. Would really love to have a furnace like yours. Electricity isn't that inexpensive, I'm sure charcoal is more expensive. I'll keep looking and saving up, sometimes they're affordable second hand. Keep experimenting, love these casting video's, I learn a lot through them!
Triangle_DIY Thank you! Yeah it would be pretty nice if I put some elbow grease into it! Yeah but I think you can buy a lot of charcoal for the price of a furnace! So a furnace would probably be cheaper in the long run. But yeah I would go for a used one if you can. If you are ambitious enough you could build your own. There is a tutorial on it. czcams.com/video/en4yhzLuD9A/video.html And another czcams.com/video/KQ7C7Hh-PD0/video.html Or you could build a simple arc furnace: czcams.com/video/JIlZsuRc9jQ/video.html
Makerj101 Yes, that's true, you can buy a lot of charcoal for the price of a furnace. But the electric furnace seems so much easier, you don't have to mess with charcoal and keeping the fire blazing etc. How much space do you have in your furnace? Second hand furnaces go for around 75-200 dollars here, if i'm patient enough I think I could pick up one for 75 dollars wich is not very bad I think. I'd rather buy one than build one. Hard to get the materials and not very cheap either. An arc furnace is really cool, maybe I'll try something like that in the distant future :P
Triangle_DIY True. It's pretty small. I wish it was bigger. It's approximately 5 inches wide, 3 inches tall, and 6 inches deep. It's a good size for small things but I can only fit a tiny crucible in it. I would love to put a bigger crucible in it. I also can't cure large plaster molds and things like that in it. But it is pretty nice. $75 dollars sounds like a really good price.
There's nothing to hold your sand together after the styrofoam is melted. Just add 10% bentonite clay (unscented cheap cat litter, crushed and sifted) and oil to your sand, compact very tight. One reason to oil is it has a much lower specific heat content than water and will not cool the flowing metal as fast as water.
The reason why the aluminum is not filling in the finer details is because your molds are too cool (room temperature) causing the aluminum to harden quicker. To fix this you can pour plaster molds, wait til they dry, then heat them in an oven or in or over your furnace and then pour the aluminum into them.
From what i have seen in these lost foam style castings is the sand needs to be wet with either water or a light amount of oil .... that way you can pack it a lot better
well everyone is giving you advice, and that is good. I want to say, nice job! you are realistic about your results and where you are. You searched for a way to get a better pour. Keep working, you'll be very successful some day.
I have to agree. You need more compacted/solid sand (or greensand) to use it. so that when the foam melts the sand doesn't fill in before the melted metal. I am guessing what your next video will be is will be blending kitty litter to make green sand.
Randall Lasini I am going to see if I can find some bentonite clay kitty litter. I think I will also try wetting the sand. Wetting might be enough. Thanks!
Support the mold with a couple drywall mud coatings thined with water. Maybe add little sand to the mud mix to minimize shrinkage. You should get a better surface finish But a bigger issue with the poor quality is the gasses in the foam need to escape. Maybe if the cups were right side up and the spruce fed into the cup from the bottom.
6:04 wow dude, congratulations! This is so fucking exciting. If I could live through two childhoods, this stuff would be a major part of the other one. "I not actually going to use it, I just want to see if it works." FUCK YEAH! You bring a tear to my eye, even though I'm only 24. Also, that cup you made was kinda cool as it was just after casting, with the foot. It was like a goblet.
Use 120 AFS Grain Fineness sand so you won't need to coat the foam with Styro Coat and you must use dry sand plus vibratory compaction when filling the mold. One other way is to just buy some Petro-Bond and 30 weight non detergent motor oil to bond the sand. I own a Non Ferrous Foundry in the USA and that's how it's done in my facility.
These are my favorite videos I think. I love the casting. I've seen one guy cast an ant hill it was really awesome. You should totally try it. Love your videos bro
oh.... other option. LOST WAX method. mix up a batch of paster of paris (50/50 mix with sand) and thoughly coat it (the heat sink) making sure you have the plaster in all crevices. Wait until it drives. then heat it in your oven up side down (lowish temp) to allow the melted foam to leak out. Then you can use the hollow mold braced in loose sand to stop it from tipping.
u need a vent on top and u need the cast to fill from bottom to top plus the sand needs to be sticky so it holds when the foam melts so it leaves a void vs filling in with sand
It looks like you are using regular sand and not green-sand. Basically you need to add a binder to your sand (fire clay or bentonite),a little moisture(very little) and mix until you can squeeze a lump of the sand in your hand and it holds shape. Also, a finer sand would help (you can try screening it thru a mesh (sieve or window screen) and use only what passes thru. Finally and most importantly, you need to create air holes. The sprue is not where your gasses should escape.Use small skewer sticks or some thicker stiff wire to poke holes in the sand until it touches your foam. make many of them. The foam vaporizes and needs to escape quickly or it will impede the aluminum flow.
+Makerj101 You still use green sand for lost foam. The point of lost foam is you can cast things that have a positive draft angle and cannot be released from a mold. The problem here was the heat nuked the foam, and the sand collapsed in faster than the aluminum could flow in.
In industry when making motor blocks they use slightly wet sand, so that it keeps its shape when compacted onto the model. This might let you make better casts as the sand won't collapse while pouring.
I love that you're showing and talking about what didn't work. Keep it up man, and great job.
I'm an engineer and was impressed with your crucible. Simple, effective, and easy to make. Awesome job.
I don't know your age but I think you are very young. You make me happy knowing there are young people out there that are interested in accomplishing something. I am a 54 year old machinist that had a father who was many things including a foundry man. I can't tell you how many times I kick myself for not asking him how to cast metal. Keep up the good work. You are an asset to your community and the world at large.
+Grady Bledsoe I just turned 20! Thank you! I will keep it up! I want to become a mechanical engineer I think! Not 100% sure yet. I've always thought machinists were awesome!
Thanks, I like your experiments.
I like that you put your failed attempts on the videos. there is nothing worse than watching polished videos. I like the learning process you go through. Cheers mate.
+Rob Molyneux Thank you! I'm glad there are some people out there like me that appreciate rough videos that include failures! :)
Hi Makerj
If you want to cast thin pieces, you have to heat your mold (sand/plaster mix) and then pour your metal.This will give the metal a chance to fill the cavity before it gets cooled by the wall of the mold. We have previously discussed this. I regularly cast 0.3mm ( 0.0118110236 inches) wall thicknesses using this technique/principal. Keep up the good work...it's impressive how far you have gotten through your own efforts.
electro1622 I will hopefully be trying using plaster casting soon. I bought some plaster recently and really want to try lost wax or lost styrofoam. I just need to get around to doing it! Thank you!
2 things:
First, your sand needs a wetting agent. Something like gummy, used motor oil or heavy silicone oil works well for sand casting aluminum. If you do that, the sand won't fall out of the packed cup as easily (no more tape) and it will pick up fine detail better. You can use other chemicals, but do not use something that attracts moisture as that can make the sand casting dangerous. I like heavy automotive greases but you can mix ingredients a bit. There's a number of lithium greases that would probably work well for this.
Second, your aluminum is seizing. You need to heat the mold.. Heating the mold prevents the aluminum from losing heat as rapidly, allowing it to flow as a liquid for a longer period of time. Even bulky pours can seize if there's a narrow gap between large volumes. Sand that can be packed tightly and hold's it's shape during heating allows the mold to be pre-heated which slows the rate of cooling during a pour and decreases the likely-hood of the aluminum seizing in an odd place.
Just going to point out used motor oil can be carcinogenic. New motor oil is safe.
Use casting sand, not play sand and pack the sand down firm. That will give a better surface finish.
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Learn more from our failures than our wins. I admire your energy and enthusiasm. Well done!
Cast the cup from the bottom up. The other way up from the way you are casting now. ( Also no problem filling the cup with sand) Your sprue goes down the side to the bottom. add straws to the top of the cup to allow it to vent out of the sand. At the moment you have no way for the gasses to escape and be replaced by the metal. Regards, Matthew
Absoutely classic engineering science. Finding what does and does not work in this way is what has led to the greatest inventions. Voted.
[I'd give this guy a job any day. He has a good engineering mind]
+Peter Hodgkinson Thank you! :)
+Makerj101 use finer sand and do a better job at compressing it, try layers.
KIDS LIKE YOU MAKE ME HAVE FAITH IN THE NEXT GENERATION. KEEP EXPERIMENTING AND DOING COOL SHIT.
I like how you used the soda straws to cast as well, gives me a really good idea for a project that I might do in the future!
I used to pour flowers and insects out of steel alloy back in the day. I never used sand because it's not holding well. I used to pour plaster around them on a vibrating table so all the air gets out. Before pouring the metal, the form was heated in an oven. Then, I used to melt the metal right in the mould, using a oxygen flame. Then we would spin the mood in a manual centrifugal machine. The pour was perfect every time, details like the hair on the spider's legs was visible while using quality dental chrome vanadium alloy.
So your problem is the mould and the feeding. Use thinner sand or plaster to increase the detail. Make the feeding rod smaller with a cooling reservoir on it, (usually a bump close to the object). Most of all, heat the mould up as close as you can to the melted metal temperature. Your mould is so cold that it cools off the metal, that is why your pour is not complete...
Let me know if you need more hints like the DIY centrifugal machine. Cheers!
Impressive video! To the point. I like the editing style and cocise explinations.
Oh i would never expect to see you here.
Just a tip. Cover the polystyrene with a coating of dry wall plaster. Mix with water to a slurry and paint on, or spray the cup with water and dust plaster over to get a thin coating. Let dry completely.
This will prevent the dry sand from collapsing into the mold as the polystyrene is vaporized. Cheers Cam.
The failed cups would make cool ashtrays. Leave the sprue and use a small round file to make a couple slots to hold cigs.
+beetlewing LOL yeah that would work! Prob is I don't smoke and I never will!
+Makerj101 As a smoker, stay that way, however it doesn't mean you can't profit off of our stupid choices
Is possible casting a cup from copper.
Interesting experiment. I did the same thing with the foam cups back in 1969, when lost foam castings was just getting started. If you want to use some really good sand that is easy to get on ebay, buy a bag of Petrobond. You won't have to mess with water because it has a binder that won't evaporate. Petrobond will provide many good molding opportunities for you, and lasts forever. Keep up the experiments. It's great to see an inquisitive mind fooling around with foundry methods.
Good video - as you can see from the comments a finer end product will mainly be the result from using finer packing materials (find sand, pulverized kitty litter etc..) but what's great about your process is it teaches the beginner the process and by doing it this way and then changing a little here and there you really develop an understanding of how it works and how to perfect it. - cheers!
+Dave Tipton Yep! Thank you! :)
Thank you for including your failures as well as your successes. Too many of these videos gloss over the trial and error part of figuring this stuff out. Great stuff. =)
Erik Thank you for seeing it that way! :) a lot of people criticize me for showing my failures. Thank you! :D
Makerj101 i think its the sand your using that is causing the issues, as the foam is being burnt away the sand is collapsing into the cavity before the aluminum can cet there, look at getting propper casting sand or green sand as its called. you can also make it, loads of vids on youtube for you to learn how to make it
chaos Regular play sand is fine for lost foam. Green sand doesn't work weel because you can't pack it properly. He could try a plaster shell. I think the type of foam isn't right. Ilso his set up needs some work.
chaos your right its the sand he isn't getting good forming sand , either get thing sand and moist it up like building a sand castle
chaos Yeah I'm planing on making some green sand really soon! Thank you!
Those experimental heatsinks turned out excellent brethren!!! Just refer to them as Art Pieces and you're golden!
The proper way to do it is to make a clay slurry. Then paint that slurry onto the polystyrene (all over except pouring hole) and let dry before you cast. This not only holds the model together when it is to be cast, but also keeps all the detail too.
Not sure if you found out yet but your problem is the sand. you need a sand that will hold some water so its sticks to it self and hold shape better. look up videos on green sand or how to make green sand
+yoududeuser yeah ok that's why there are like 1000 CZcams videos of exactly what I'm talking about. Instead of being a moron why don't you look up the videos that already show people doing exactly what I'm saying.
+yoududeuser sorry I apologize. Dealing with trolls today.
+yoududeuser Because you're being a moron, spewing false information and potentially scaring some people.
A good saying you should follow: If you don't know what you're talking about, keep it to yourself.
+yoududeuser Seriously, dude - you contradict his solid advice screaming, "NO!" - so he is justifiably compelled to scream over YOU. Then you go and get all butt-hurt. Ridiculous. He did not owe you that apology, so don't go thinking you deserved/earned it.
+AGENT CHAOS Naaaaah, that's bullshit. You end up with a shit ton of steam in your cast, ruins surface quality. I tired it, was aweful, upgrading to real casting sand shortly.
Wrong sand Mate, research for the right sand and keep at it, you're an inspiration to many.
hey man. i just had some thoughts from my own personal experience on how to cast whatever you want quite easily. I do some lost foam casting and normal flask castings, but i use greensand for both.
The advantage of green sand is its a bunch of sand particles coated in bentonite clay. It holds whatever shape you mold it to quite well. you can basically take a normal object of any material, make a mold of it with that sand, and its holds the shape for the metal while it's poured in.
but the reason i suggest it is because it looks like as the foam burns out your sand shifts and cuts it off. if you used green sand it wouldnt move and it would just cast the object you're after quite accurately.
I went to petco and bought some natural terrarium sand for reptiles. mostly because its super fine sand, and its already filtered for any larger rocks and such.
a 10 lb bag is 15 bucks. then i mixed that with a 1 lb bag of bentonite clay. which i purchased for about 5 or 6 dollars off of ebay.
the trick is to mix the two together really well dry, then slowly use a spray bottle to add water and keep mixing, just until you can squeeze it and it holds it shape without crumbling super easy. you want clean breaks.
keep it in a sealed container. don't let it dry out. and after each use i take all the hard dry bits and break them back up and mix them back into the sand and add more water if necessary. you can re-use it hundreds of times.
hope this helps :D
this helped me alot, thanks mate!
This is great! I actually enjoyed seeing you learning from the early casting, because I think it will help me avoid those mistakes. Great job, and keep on making!
The heatsink with the straws turned out really cool. Great video.
Your furnace is more innovative than anything I would build.
Great job. I learned the straw vent bit. The option with the thin wall stuff would be to pull a vacuum on the vents. Just an idea.
On thin sections the foam outgases then the sand collapses before the metal can fill the void. Two things you could try --
1) make a very thin slurry of plaster of paris and paint it on. Once you get the thickness you need bake it dry. NOOO wet plaster! Then follow your normal LFC methods.
2) Find a high temp paint that you can coat the foam cast with. You will have to experiment here, many paints have esters that eat the foam, some don't. Once coated follow your LFC methods.
This provides a skin to resist the void collapse so the metal can fill the void. Good vid.
I would say try making the sand a little more damp. Green sand is typically what is used for casting, you might want to experiment with that.
s28400 Yeah I think I will try dampening the sand. Thanks!
Thank you for the tips, im learning something new every video from you!
All the problems you are having are due to your sand.
You need to make yourself some green sand. Plenty of advice online and youtube.
Matt
Matthew Gischus I will see if I can find some bentonite clay kitty litter. I think I will also try wetting the sand.
Mike Studmuffin Yeah it totally could. But as long as you don't use much water it's fine. Green sand has water in it(except the oil based stuff). But it's only like 3% water or something. At those amounts the steam can escape fast enough through the sand. A volcano of molten aluminium would not be fun hahaha
Makerj101 If you are looking for bentonite, I would see if there are any small well drilling companies around your area. They use Bentonite clay powder that is so fine it's amazing. Its used as a drilling lubricant. That way you don't have to fiddle around trying to grind kitty litter to a powder. In a lot of cases, you can tell them what you are doing and they might even give you a little in exchange for showing them what it will be used for. Also, I think farmers Co-ops will sometimes have it, used for various things like sealing the bottom of fish ponds and such. Thanks for sharing
Maybe use water to pack the sand but then let the pot dry out in the sun for a day, I'd say cook it but it could melt the styrofoam. Blow dryer in a cardboard box?
Good job. Its nice to see someone as young as you taking an interest in doing things like this. If you ever go to Pick-N-Pull auto salvage, look at the aluminum cylinder head castings and you will see nice clean imprints of styrofoam forms.
kimmer6 what you in calgary
Nope, thousands of miles Southwest.
The casting (green sand) idea many are propounding here is what you need, but be very careful with what you pour and wear at least boots and a face shield when you do it. You will need exhaust vents too as this gets really dangerous if you have an area of sand that is surrounded on all or most sides (as in the case of a downward facing cup) by molten aluminum. You'll get superheated steam in an instant (from the moisture in the greensand) and, if it has nowhere to vent, it will cause a small explosion in the molten aluminum by trying to escape through it, potentially showering you with the hot aluminum. Anyway, it's wonderful to see a young person interested in interesting things rather than pursuing nonsense. Keep up the good work and keep experimenting and it will pay big dividends later.
Wow dude. Based on your voice, I always thought you were like 13! But then you had a beard.
Brandon D LOL yeah I'm 19!
+Brandon D me 2
You did a good job with your early attempts! Cope, drag, sprew, riser, gates, are all terms you need to know a little more about. Green sand is a combination of clay, sand and water. It is has been awhile since I took my foundry class in college but I will tell you there is already some good information in the comments down below. I don't remember any oil used for any castings in my foundry class. I had also forgotten about parting dust until a friend reminded me when we were pouring stuff in his back yard foundry. A good parting dust for a home foundry is baby powder.
You need to use green sand. The metal is more dense than the sand you're using and it is pushing the sand out of the way which is affecting your detail and resulting in the incomplete molds. You also need to compact the sand in layers around the mold as tightly as possible. Make or buy some green sand and you will notice a world of difference.
your video quality is great and you're very informative. stick with it man because watching you try and learn how to do it is even more entertaining and educational than most videos on similar topics.
start a gofundme for your videos! it's worth a try!
earned a subscriber and a thumbs up in the first 60 seconds, good job man!
Nice vid thanks. Like other people said green sand would help. Or an alternative is to paint on a thin layer of plaster, over the foam. It takes time as the plaster has to be well dry before you pour, but hat will stop the dry sand collapsing in and spoiling the casting.
I'm pretty sure part of the issue here is with the type of styrofoam you used. Some styrofoam is very light, while some is denser. Styrofoam cups (and plates and bowls) are made of slightly denser styrofoam, and some of them have a slightly plasticized surface to prevent leakage. So, rather than instantly vaporizing, they melt, producing a barrier to the clean flow of aluminium. I have cast some very thin styrofoam sheets successfully when I used expanded polystyrene insulation that I cut into thin sheets myself, rather than using pre-made thin products such as plates and cups.
God I wish the internet was around when I was your age. Nicely done :-)
you'd have better luck if you used something to dampen the sand...either a finer grade greensand using water, or an oilsand so it can be compacted and will retain it's shape better
find an old metal shop text book and study up on some of the methodology (or check on line, there's lots of good resources; just google "lost foam sand casting" casting using lost foam is very workable and allows for complicated detail that is otherwise impossible in an ordinary cope/drag format. But you need something to stabilize the sand while the foam is melting away. One site I know of on CZcams, he coats the foam in wallboard mud, gives it a couple days to dry hard, then fills in around it with sand. Such a method can give truly impressive results....
wd40 seems to work well for firming up the sand. Makerj, your sand is caving into your mold as the foam melts faster than the metal can flow. it doesn't take much to hold the sand for a split second longer and improves pours dramatically.
I think the problem is thinner sections solidify very fast and don't let molten metal to go further. You may add additional runners to these sections.
I found this really fascinating. As already mentioned by others, I suggest you have some exit vents to aid the flow as well as the entry point. This will be even more important once you start wetting the sand as I think right now most of your air is escaping through the dry sand. I'm looking forward to watching more of these vids as you progress along your road to discovery. Makes me want to have a go!
Love your videos. Keep the good work.
Greatings from Brazil
Some suggestions:
Try manufactured sand. It has sharp, angular particles that interlock and cling together.
Make a wooden frame, place it on a board and put the polystyrene cup inside, right-side-up. Then fill it and surround it with 'green' sand. (slightly moistened sand.) Inverted the whole assembly sharply onto a flat surface. (concrete or granite should be okay.) The base of the cup should now be on top and that is where you pour.
Maybe I'm wrong, but I think that aluminium heatsinks are made in bulk by machining solid blocks of aluminium, because not even with perfect sand (or plaster or ceramic) casting can you get heatsinks as perfect as when you machine it. That's why the compressor blades of the turbochargers are made by machining too.
Take kitty litter and pulverize it the consistence of talcum powder. mix it with fine plaster sand. Your sand needs to be moist but not too wet. About like what you would need to make a sand castle. Put foam in sand and tamp it. you will get good results.
+Jeff Stone LOL I just posted a video about this a couple of hours ago! czcams.com/video/DCYUgq-Awfg/video.html&lc=z12jjphojui0hzk0u22uvrdqrm2tgljrn04 Thank you!
Plaster is not that expensive and it provides better insulation as to not let your aluminum loose as much heat so you can get much thinner casts! You can also crank the heat up waaaaay more. If you cast the Styrofoam inside the plaster I don't see why you couldn't get much better pours! Just make sure to get all those air bubbles out
Another idea would be to cast the Styrofoam inside the plaster and burn it away inside of your furnace! This would also allow for all of the moisture to be removed from the plaster. If you do a 50/50 sand and plaster mix you could also play around with making some reusable molds but it'd take a little bit more planning and possibly some more failures! Let me know what you think!
You need to make channels coming off the bottom of the cups so that the air can escape. The molten metal is getting air trapped and hardening before the metal can make it all the way to the bottom.
Hey young man do some research on making green casting sand I think its hot enough but the sand is closing in on the foam that is why the double cup method worked better. good hobby keep it up.
Use 2 X 4's or 2 X6's to make a good drag (the bottom part of your two part system), use the same thing to make a cope. Fill the bottom with your green sand (clay water and sand combination) set the cup full of moist, not wet sand (packed as tight as you can without breaking the cup) on the bottom half of the mold you cold cut Q-tips in half to make a fair number of gates running off the top, which is now the setting on the bottom half of the mold. Set the top half of the mold on top of the bottom half and use a regular number two pencil to make a riser. Fill the top half of the mold with more green sand. Once it is all packed into place you should be able to separate the top and bottom half of the mold you can then cut a runner to the riser into the bottom half of the mold. You can also remove the Q-tips. The gates will provide extra heat down at the bottom for the thicker part of the cup. Use something round to make the sprew and make it conical near where you are going to pour it in. With green sand you should be able to remove the thing you used to make the sprew, just like you can remove the number two pencil before you pour. The only thing you are trying to melt away is the foam cup. I was not able to read all 495 comments, but you sure got a lot of peoples attention if you got that many comments. Good job.
Myfordboy on youtube uses washing soda to degas his aluminum. Also recommends only using previously cast aluminum rather than extruded or tin cans. I'm impressed with what you are doing. Thanks for sharing.
Oh and excellent work. It's so nice to see a bright young mind doing hands on stuff and learning as you go! Stay safe.
Great work! You've got the right idea...always look at the outcome and ask yourself " is this what I expected".If the answer is "no" then formulate more questions! Be careful of using water and sand when casting molten metal!! Green sand must be proportioned very carefully!! Too much water and the molten metal will cause the water to instantly vaporize and potentially cause an explosion (just watch some of the videos of folks melting aluminum pop cans).
Keep experimenting....
Here's a hint... It looks like most of your metal is solidifying in the sprue! What about positioning the heat sink foam molds horizontally in the sand and feeding the metal through several sprues (a manifold) to distribute the molten aluminum more effectively.
i honestly dont know much about aluminum casting, but it looks like you are using regular sand as opposed to the red sand meant for casting, which feels more like clay than sand. if that is the case, the problems you are facing may be due to the sand collapsing in on itself as the styrofoam burns faster than the aluminum can flow in. but that is just a guess, based on being a mechanical engineer, and not being an expert on casting or anything
Brilliant these things are a work of art , no matter the imperfections , keep it up , Nice
Oil the sand a bit and ram it into the mold. You'll have to work out a sequence to keep the styrofoam from collapsing. Also consider making a core from the inside of the cup and then fitting a negative of the outside of the cup over it. The thin styrofoam seems to be able to keep the aluminum out of the cavity by gas pressure or cooling of the metal.
You should use "green sand" dampened to do deep foam and fine casting. Plaster of Paris is the norm though.
You can get a better copy of finer objects if you use the plaster method and not have as much rough texture.
Also to make small things like jewelry, shims, pins, etc. you maybe should cast them in a flat down position, take you damp sand and carve out the designs and pour them. after they cool hit them with a bench grinder carefully with a fine wheel to trim them up and smooth them out. Again you can plaster cast them too.
Not in the sake of saving power and time you can try the DIY arc furnace method by using carbon rods, fire brick and an MOT. This will eliminate the need for a crucible as you can bore the brick out and even give it a pour spout. There are youtube videos on how to build one cheap using MOTs.
An arc furnace can get hot enough to melt aluminum and even steel in a very short time. I am designing one myself to have for when I need a special custom bracket, or spacer or whatever made from steel, copper, brass, etc.
Seems like a useful thing to have in the shop.
ElfNet Gaming I am going to try to find some bentonite clay kitty litter to make some green sand. I also really want to try lost wax casting using plaster. I bought some recently so hopefully I'll get around to it soon!
Yeah Grant Thomson! I've seen those mini arc furnaces and they are awesome! I have some nice big carbon rods too! :D But they are kinda antique so I'm not sure I want to use them...
Those rods are TOO BIG! use the rods from spent 6v batteries like Grant did. That's what I'm going to use.
ElfNet Gaming True. I have a couple from AA batteries but they are a little small I think.
Hey, I actually think the pouring went wrong because the sand collapses under it's own weight. The bottoms of the cup melt and the sand just sags down in. This might well be the reason of the fails. You could use denser sand types that come pre-mixed with a type of oil to preserve shapes inside.
Good video. You show it all, not just the successes. Keep it up and we all learn. Thanks
Aluminum ashtrays!!!! I woulda been so happy with this 😂
To be more precise the foam is not all really being melted by coming into contact with the metal. It is burning from the heat that precedes the metal so that the sand collapses. I agree that wet sand or some other sand will hold its shape longer as the foam burns out.
Your Creativity and Imagination is quite Unique...Nice
I use casting sand, and when I am about to start the mold, I use baby powder and brush it on the original... then when I use the casting sand, I pack it in... use some method of vents, similar to the straws you used.
hope these tips help you out.
make sure the casting sand is NOT dry... has to stick to itself.
have fun!
What type of sand are you using? You do know that casting requires a special silica sand? Just an idea, thought it might help.
If I can suggest using wet sand as it will be more structural when the foam is melting away. In your heat sink the sand is filling in faster than the molten aluminum after the foam melts. Good luck
love ur alluminium casting vids!
carson1_1 Thanks!
Smart kid.. outstanding. Its great to see your learning. Keep going.
+Al Libowitz Thanks!
This is absolutely amazing, you did a great job. Even better results then linustechtips who tried to make a heat sink
that is the coolest intro ive ever seen
Your problem, in regards to casting the cups, is that you're using 1 large sprue leading to the thin bottom of the cup and expecting that you don't have so much heat loss that it allows the molten metal to travel all the way (again, along thin walls, exposed to lots of cooling sand) to the lip of the cup....
You need more channels, leading to the outer edges of the cup bottom, from the main sprue, which will allows more heat retention... You should also heat your metal WELL ABOVE the actual melting point (at least several hundred degrees fahrenheit) so that as the metal cools it doesn't solidify immediately upon contact with the sand.
+digitalmunky Thank you very much for the helpful tips! I will try some of them on my next castings!
yeah i think the problem your having is the sand its too loose and instead of the gasses venting out the pour hole or vent holes they are out gassing form the whole mold so your getting a rough cast.
you are really good at this, im amazed and cant wait to start doing this.
Awesome work man I really like how convenient that electric furnace is!
Your gonna go a long way, kid. Good work!
Yes oil in the sand and tamp it in. they usually have a spru and a riser vent, also dusting it with talc will make finer detail.
the commercial casters dip the Styrofoam in a slurry of alumina powder , you may try plaster of paris to give it a coat of light skin , let it dry and you got a perfect cast.
+sam terian I read that a slip made from powered drywall patch (mix it yourself, not the premixed) works well.
Wow, nice video! That cup is awesome! Maybe if you just try it another time it will be perfect. You could sand down a little bit of the top part and keep it on the stand, then polish it, would be nice :)
Nice experiments, gives me some inspiration for when I start again with casting, when I have time, and the weather is good at the same time. Would really love to have a furnace like yours. Electricity isn't that inexpensive, I'm sure charcoal is more expensive. I'll keep looking and saving up, sometimes they're affordable second hand.
Keep experimenting, love these casting video's, I learn a lot through them!
Triangle_DIY Thank you! Yeah it would be pretty nice if I put some elbow grease into it!
Yeah but I think you can buy a lot of charcoal for the price of a furnace! So a furnace would probably be cheaper in the long run. But yeah I would go for a used one if you can. If you are ambitious enough you could build your own. There is a tutorial on it. czcams.com/video/en4yhzLuD9A/video.html
And another
czcams.com/video/KQ7C7Hh-PD0/video.html
Or you could build a simple arc furnace:
czcams.com/video/JIlZsuRc9jQ/video.html
Makerj101 Yes, that's true, you can buy a lot of charcoal for the price of a furnace. But the electric furnace seems so much easier, you don't have to mess with charcoal and keeping the fire blazing etc. How much space do you have in your furnace? Second hand furnaces go for around 75-200 dollars here, if i'm patient enough I think I could pick up one for 75 dollars wich is not very bad I think. I'd rather buy one than build one. Hard to get the materials and not very cheap either. An arc furnace is really cool, maybe I'll try something like that in the distant future :P
Triangle_DIY True. It's pretty small. I wish it was bigger. It's approximately 5 inches wide, 3 inches tall, and 6 inches deep. It's a good size for small things but I can only fit a tiny crucible in it. I would love to put a bigger crucible in it. I also can't cure large plaster molds and things like that in it. But it is pretty nice. $75 dollars sounds like a really good price.
There's nothing to hold your sand together after the styrofoam is melted. Just add 10% bentonite clay (unscented cheap cat litter, crushed and sifted) and oil to your sand, compact very tight. One reason to oil is it has a much lower specific heat content than water and will not cool the flowing metal as fast as water.
The reason why the aluminum is not filling in the finer details is because your molds are too cool (room temperature) causing the aluminum to harden quicker. To fix this you can pour plaster molds, wait til they dry, then heat them in an oven or in or over your furnace and then pour the aluminum into them.
From what i have seen in these lost foam style castings is the sand needs to be wet with either water or a light amount of oil .... that way you can pack it a lot better
That sprew made it look like a cool goblet you should leave it that way
well everyone is giving you advice, and that is good. I want to say, nice job! you are realistic about your results and where you are. You searched for a way to get a better pour. Keep working, you'll be very successful some day.
I think your crucible is brilliant. Thanks for sharing!
I have to agree. You need more compacted/solid sand (or greensand) to use it. so that when the foam melts the sand doesn't fill in before the melted metal.
I am guessing what your next video will be is will be blending kitty litter to make green sand.
Randall Lasini I am going to see if I can find some bentonite clay kitty litter. I think I will also try wetting the sand. Wetting might be enough. Thanks!
This dude is a engineering wiz!!!
Support the mold with a couple drywall mud coatings thined with water. Maybe add little sand to the mud mix to minimize shrinkage. You should get a better surface finish
But a bigger issue with the poor quality is the gasses in the foam need to escape. Maybe if the cups were right side up and the spruce fed into the cup from the bottom.
6:04
wow dude, congratulations!
This is so fucking exciting.
If I could live through two childhoods, this stuff would be a major part of the other one.
"I not actually going to use it, I just want to see if it works." FUCK YEAH! You bring a tear to my eye, even though I'm only 24.
Also, that cup you made was kinda cool as it was just after casting, with the foot. It was like a goblet.
Use 120 AFS Grain Fineness sand so you won't need to coat the foam with Styro Coat and you must use dry sand plus vibratory compaction when filling the mold. One other way is to just buy some Petro-Bond and 30 weight non detergent motor oil to bond the sand. I own a Non Ferrous Foundry in the USA and that's how it's done in my facility.
+Michael Nedesky In my newest videos I show how to make green sand and I cast a nice flywheel with it. Thank you!
Hey if you use damp sand/ clay that you really pack around what your molding it will help improve the quality of it
HunterPayne4 Yeah I'm gonna try that! Thanks!
These are my favorite videos I think. I love the casting. I've seen one guy cast an ant hill it was really awesome. You should totally try it. Love your videos bro
Ron Covenant I really want to! Thank you!
Right on. Good to see a younger fellow interested interested in real life skills. Keep practicing. :)
oh.... other option. LOST WAX method. mix up a batch of paster of paris (50/50 mix with sand) and thoughly coat it (the heat sink) making sure you have the plaster in all crevices. Wait until it drives. then heat it in your oven up side down (lowish temp) to allow the melted foam to leak out. Then you can use the hollow mold braced in loose sand to stop it from tipping.
Randall Lasini I also want to try lost wax! I bought plaster recently so I will hopefully get around to doing that soon. Thank you!
u need a vent on top and u need the cast to fill from bottom to top plus the sand needs to be sticky so it holds when the foam melts so it leaves a void vs filling in with sand
It looks like you are using regular sand and not green-sand. Basically you need to add a binder to your sand (fire clay or bentonite),a little moisture(very little) and mix until you can squeeze a lump of the sand in your hand and it holds shape. Also, a finer sand would help (you can try screening it thru a mesh (sieve or window screen) and use only what passes thru. Finally and most importantly, you need to create air holes. The sprue is not where your gasses should escape.Use small skewer sticks or some thicker stiff wire to poke holes in the sand until it touches your foam. make many of them. The foam vaporizes and needs to escape quickly or it will impede the aluminum flow.
Don't you need to add somthing to the sand and pack it down to make it bond together so when the syrofome melts the sand doesn't cave in?
Brad R That's for green sand casting. This is lost foam casting which is a little different. You can use dry sand with this method.
+Makerj101 You still use green sand for lost foam. The point of lost foam is you can cast things that have a positive draft angle and cannot be released from a mold. The problem here was the heat nuked the foam, and the sand collapsed in faster than the aluminum could flow in.
In industry when making motor blocks they use slightly wet sand, so that it keeps its shape when compacted onto the model. This might let you make better casts as the sand won't collapse while pouring.