Metal Casting Zone

This is something I have been working on for nearly six months. I finally have something to show for it and decided to bite the bullet and put it out there for everyone to peruse. This is the MKI version, as I get a few more projects off the list, I will start work on the MKII and hopefully come a little closer to what I had in my head for this. This one turned out a bit crude, but it does work.


This is the crucible I made with it.



It is epk clay/graphite/alumina with a small amount of 110 mesh sand. I fired it at white hot temps for about 45 minutes after ramping up the temp over a couple of hours. It sintered very nicely but it does have a small crack in the inside bottom.


I don't know if it goes all the way through, and I will be testing this one with aluminum and maybe brass. Here is how it goes together:




These are the patterns:


They were done as a near disaster in lost foam. They came out horribly rough and a bit distorted. it took several months on and off of grinding, sanding, and filing to get them to a useable point. I almost chucked em a few times in frustration. The bottom ring and top press were done in lost foam as well. The fit and finish isn't where I want it, the pics make it look a lot better fitting than it really is. This was to be my better mousetrap, and may still be with the MKII version. I would like to build them in several sizes and sell them, maybe even custom sizes. Whaddya think, guys?

i like it. crucible making is one of my next projects before i build my new furnace. i have a copy of the gingery method thanks to rob who obtained a copy for me. upon reading it i immediately thought of something similar for the mold but i was going to arrange things so i can use my 50 ton bottle jack to do the final press after ramming. i was going to make the outside mold square so i could put a long bolt through it. the inside similar to yours its a great idea and if the price is right??

Very nice, and one more completed project. If your anything like me you have probably added 10 more to the unfinished project list lol.
? will it hold up to an iron melt?

based upon my research i would say the mix that used was designed for brass and cant see any reason why it would fail.a glaze could be added.

That looks great OddDuck. Have you thought of doing a matchplate pattern with cores instead of lost foam?

Thanks guys. Yeah, Jammer, I have thought of doing a match plate, I have that method in mind when I finally have time to crank out the MKII. The execution on this one left a lot to be desired. The initial pattern was foam, but now I can use the aluminum patterns to make more, although I don't think I will cuz I aint happy with this version. Picky barstuhd, aint I? This one was more a proof of concept (and the fact that I'm too damn stubborn to give up on an idea easily).
XL, great minds think alike, that was my thought exactly with this one, just pour in a measured shot of clay mix, put it in the press, and out pops a crucible. I also though of using a vaccuum bag with it, that would provide quite a bit of pressure and maybe help make an even denser final product.
I haven't had time to do another melt with that crucible, and I hope it will stand up to iron. Crucibles are a consumable item when doing iron, and I wanted to come up with a way that I didn't have to spend 30 bux every ten melts or so.
I have thought of glazing it, there must be a glaze that will help the crucible resist the very fluxy iron charge. I have heard that they use magnesia in industry, but I am fresh out at the moment. Epsom salt is magnesium sulphate, I wonder if doing a wash with that would help?

$30 is cheap compared to what they here in oz. the cheapest is a no 4 at $85 plus postage. as luck would have it i found out about "lost and foundry" in spokane who can supply crucibles just!!!!!! as my stepson was in flight comeing back home after 2 yrs in SPOKANE!!!knows the place quite well and all that. he goes back in a bout a years time maybe eariler so i have a little while to get crucible making up and running. if i fail i will get him to get me some and send them over. i did chase some crucibles on ebay . they were found on old gold mining sites here and were made in britain about a hundred yrs ago.they went for more than a new one.

I think I saw the same ones, XL. I don't think I would trust a crucible that had been used a hundred years ago and then dug up. Might be a few structural issues. $85 for a #4? Wow. Is that $85 Austrailian or US? I don't have the link right handy, but Google a place called Legend Mining Supply, they are about the cheapest source of clay crucibles here in the states, and I have heard good things about their quality. They sell in cases of six, and I think a case of #10 clay-graphite is about $140. They probably ship international, but I bet it would be pricey. I'd offer to cast you one and ship it but again it would be quite uncheap. I haven't weighed the halves but I bet the ship weight would be at least 25 lbs.

OddDuck, what's the consistency of you crucible mix? Is it runny like a milkshake or a stiff dough, or fairly dry and crumbly? Anytime I think about making some, I wonder how to pack it in the mold without having seams and voids. I think liquid would fill the best but too much water makes some clays weak.