ErictheRed1990 Posted December 9, 2011 Share Posted December 9, 2011 So really simple question... i have a general idea of forming one, BUT i havent seen the answers anywhere... Can i make them out of plain refractory cement? Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 9, 2011 Share Posted December 9, 2011 I know folks who've done it. What do you plan to melt? Quote Link to comment Share on other sites More sharing options...
ErictheRed1990 Posted December 9, 2011 Author Share Posted December 9, 2011 well thats the thing im not 100% sure... for starters just iron maybe just to get a feel for it.. whats the simplest thing to melt? Quote Link to comment Share on other sites More sharing options...
Jacques Posted December 9, 2011 Share Posted December 9, 2011 The crucibles I've got is made from graphite. If I were you I would buy the right stuff. Having played around a bit trying to make my own to melt aluminium the commercial ones are so much better and not expensive at all. Unless you would like to experience the pleasure of seeing a crucible failure. This remind me of that quote I've read once: "Molten alumnium vapourise flesh instantly." Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 9, 2011 Share Posted December 9, 2011 Iron is very far from the simplest metal to cast. If you're new, start with aluminum.And you need to do a lot of reading ahead of time, with a particular emphasis on safety. There's a good bit to learn. Lindsay Books sells a number of good titles. The books by Steve Chastain are very good. And as Thomas P always points out, you can get them from your library via inter-library loan. Quote Link to comment Share on other sites More sharing options...
dimenickel Posted December 9, 2011 Share Posted December 9, 2011 to make a good crucible is a difficult thing... especially one that is to hold liquid iron at 1535 cel.. the few i made from refractory cement or castable failed quite nicely - now i just buy clay graphites from vesuvius and have never looked back Quote Link to comment Share on other sites More sharing options...
ErictheRed1990 Posted December 9, 2011 Author Share Posted December 9, 2011 ah ok, well the problem around me is not much in the way of blacksmithing/ smelting shops so id have to order it..and not on much money. so what kinds of places have graphite..? Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted December 9, 2011 Share Posted December 9, 2011 So you want to possibly spend *more* money and risk extensive hospital time to make your own? And by "iron" you do mean cast iron and not mild steel right? Molten metal is much more dangerous than hot steel that may be hundreds of degrees hotter. I suggest you start hanging out at BackyardMetalcasting.com and find someone within a possible driving distance and get hands on training *before* you try it yourself. You do know that the protective equipment needed for casting iron will not be cheap right? Quote Link to comment Share on other sites More sharing options...
ErictheRed1990 Posted December 10, 2011 Author Share Posted December 10, 2011 yaaaa i know it wont be cheap to get started, im just looking into ways to get started the safest and most inexpensive as i can lol ....but i have no idea if this is true...but i heard aluminium is unstable when its being melted or w.e? if it comes into contact with any water? is this true? Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted December 10, 2011 Share Posted December 10, 2011 ALL molten metal can cause explosions when they come in contact with water! Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 10, 2011 Share Posted December 10, 2011 Water expands its volume by something like 1600 times when it flashes to steam. If it happens to be covered with molten metal, nasty things happen. Since nearly all molten metals have a melting point *way* above the boiling point of water, they will flash water to steam instantly if the two come in contact. If you put a skimmer that hasn't been preheated into a crucible full of molten metal, or pour a molten metal into a metal mold that hasn't been preheated, or add metal to the molten charge without preheating it . . . you get this:http://www.liveleak.com/view?i=93a_1251647793 This is the kind of thing I was talking about when I said you need to read up on the safety aspects of casting before you try it. Green sand casting involves moist casting sand. The difference there is that the sand is porous, which lets the steam escape without building up any pressure. Quote Link to comment Share on other sites More sharing options...
Kendall P Posted December 12, 2011 Share Posted December 12, 2011 You havent grasped the magnitude or danger involved in your "Just melt some iron" idea. Please transfer that enthusiasm to teaching yourself by reading a few books and checking out some of the many helpfull websites and previous threads. Quote Link to comment Share on other sites More sharing options...
Old N Rusty Posted December 12, 2011 Share Posted December 12, 2011 "More dangerous than a monkey with a machine gun". If you " just melt some iron" with a complete lack of training, or experience. You might find out what that means. Quote Link to comment Share on other sites More sharing options...
ErictheRed1990 Posted December 13, 2011 Author Share Posted December 13, 2011 obviously i was in over my head no point denying it, so i have been reading about it ...starting to.. lol thanks for the advice guys , more fun to read and do it right then end up killin myself yes? but i have another question, it being, i read about sand casting with silica sand... now..I use silica sand at my job with pools... its a ...whiteish harsh sand...is that the same kind mentioned? Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 13, 2011 Share Posted December 13, 2011 Yeah, basically, although commercial casting sands use specific mixes of different proportions of different grain sizes to give the sand the desired properties (porosity, green strength, moldability, surface finish, etc.). And of course it needs a binder -- bentonite clay for "green" (clay-bonded) sand, with just a little water. Quote Link to comment Share on other sites More sharing options...
Dodge Posted December 15, 2011 Share Posted December 15, 2011 That video still has me in AWE!! They put the crucible on the bench !! They are trying to put the flames out and they leave the crucible on the bench!!! :blink: Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 15, 2011 Share Posted December 15, 2011 I'm not sure what's burning, but it looks like they may have a metal plate about 1/4" thick on the part of the bench where they're working, although even that doesn't seem adequate to me. You can see a square, gray, metallic looking, plate, roughly 2'x2', sitting on the bench in the closeup right before the eruption. The ingot mold seems to be on top of it. Again, that still doesn't seem like enough to me. That mold will get hot, and so will the plate. Quote Link to comment Share on other sites More sharing options...
ErictheRed1990 Posted December 15, 2011 Author Share Posted December 15, 2011 well man ! comon they are Professional look at em, id trust em! ;) Quote Link to comment Share on other sites More sharing options...
MattBower Posted December 15, 2011 Share Posted December 15, 2011 Clearly those guys didn't have adequate training, but I'd expect whoever set up the lab (and I'm sure it wasn't them) to know a little better. Quote Link to comment Share on other sites More sharing options...
ramsies11 Posted February 18, 2012 Share Posted February 18, 2012 those kids were extremely lucky. they wernt wearing hardly any safty gear at all. Quote Link to comment Share on other sites More sharing options...
Bentiron1946 Posted February 20, 2012 Share Posted February 20, 2012 Lindsy Press has a booklet on how to make your own crucibles suitable for casting aluminum but it takes a fair amount of work to make them, it just isn't that simple. I got to an iron pour in New Mexico every March and there for toting the molten cast iron from the coupla to the molds we line metal waste baskets or 5 gallon buckets with refactory material and when we tap the coupla we fill these up. However by the time the pour is over they are pretty much used up. There is a vast difference between using refactor material as a linning and useing it for the actual crucible, graphite in my personal opinion is still one of the safest crucibles. I have paticapated in pours where we had to use a fork lift to get the crucible out of the melting furnace to pour a life sized man and these crucibles were all graphite and they were not home made concoctions either. Quote Link to comment Share on other sites More sharing options...
MattBower Posted February 21, 2012 Share Posted February 21, 2012 those kids were extremely lucky. they wernt wearing hardly any safty gear at all. Indeed. But the biggest problem of all is that they didn't know what they were doing. No one had told them to preheat the ingot mold to drive off moisture, and even the supervisor who came in at the end didn't seem to grasp the problem (although, in his defense, he hadn't had a lot of time to think about it). That's why I've posted this video several times. I think it drives home some important points. Now imagine if that were 20 pounds of bronze or cast iron instead of a pound (or whatever) of aluminum. Quote Link to comment Share on other sites More sharing options...
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