Metal Casting Zone

has anyone used one or has plans for the building of one??

this is kinda what i have in mind. checkout the thermite castings.
www.theodoregray.com/PeriodicTable/Elements/026/index.s7.html#sample14

Hi.
I designed a thermite powered furnace I call the starchamber. You can see a rough sketch of the basic design and a type of steel I made, plus a cheesy video of it in action here... http://www.knifemakerforums.com/showthread.php?t=66

this is great! harnessing the power of thermite and doing something useful with it.its my ambition to build a small furnace.

xlchainsaw wrote:
this is great! harnessing the power of thermite and doing something useful with it.its my ambition to build a small furnace.
I've got lots of notes and pictures, if you need them.
That furnace is mainly designed to alloy reactive alloys. You can simplify it for simple steel or alloys. I am designing a titanium version to start trying making new titanium alloys, but that one wont be on the boards soon, (advice from my patent lawyer)

Let me know what you need, Jerry

Jerry Bennett wrote:
xlchainsaw wrote:
this is great! harnessing the power of thermite and doing something useful with it.its my ambition to build a small furnace.
I've got lots of notes and pictures, if you need them.
That furnace is mainly designed to alloy reactive alloys. You can simplify it for simple steel or alloys. I am designing a titanium version to start trying making new titanium alloys, but that one wont be on the boards soon, (advice from my patent lawyer)

Let me know what you need, Jerrysure will! im just finishing my lathe (gingery) that i cast bits for and then im ready for the next project. my shed is filling with aluminium grindings and i have plenty of rusty steel and fire clay.im thinking of making molds out of fireclay and letting the charge just drop and fill. i watched your vids and as i live in the city i will have to watch the smoke part! something about the size of two paint cans together???

xlchainsaw wrote:
Jerry Bennett wrote:
xlchainsaw wrote:
this is great! harnessing the power of thermite and doing something useful with it.its my ambition to build a small furnace.
I've got lots of notes and pictures, if you need them.
That furnace is mainly designed to alloy reactive alloys. You can simplify it for simple steel or alloys. I am designing a titanium version to start trying making new titanium alloys, but that one wont be on the boards soon, (advice from my patent lawyer)

Let me know what you need, Jerrysure will! im just finishing my lathe (gingery) that i cast bits for and then im ready for the next project. my shed is filling with aluminium grindings and i have plenty of rusty steel and fire clay.im thinking of making molds out of fireclay and letting the charge just drop and fill. i watched your vids and as i live in the city i will have to watch the smoke part! something about the size of two paint cans together???

That's good you save your aluminum fines. That's what I do. Keep in mind that some aluminum is alloy, like 7075. It contains a fair amount of copper and zinc. The zinc will burn off, but things like copper, will end up in your steel. You don't want that.

The iron oxide is best purchased from a pottery supply. It is very pure and fine, (important. more surface area for the aluminum to grab the oxygen atoms). The size of the aluminum fines is not as critical as the iron oxide. Be sure to buy iron oxide II or III, the red stuff and not the black. Fireclay works well. Even better with a little magnesium oxide.

You need to pack the charge very well and use a small mild steel plug at the bottom.
This will make a slower, hotter, more controlled burn and a better cast. Save the slag, as it in itself is a good refractory. In fact, it will line the reaction crucible as it burns from the top down, to bolster the refractory. Remember, a thermite flame burns from 7 to 8000F. The liquid iron is from 4 to 6000F, depending on the size and duration of the charge.

Here is a vid of one of my early runs. I set it up to drop into a crucible, that is in a charcoal fire, fed with a draught. It melted through the side before tapping. Quite spectacular, but notice it's still under control. I designed an integrated furnace to utilize the heat better. enjoy. http://s63.photobucket.com/albums/h151/BrentFinnigan/?action=view&current=MOV01705.flv&refPage=&imgAnch=imgAnch1

wonderful vid. from what you have shown and some fine tuning i think a thermite powered furnace is the way to go especially if it had a crucible in it. it sure beats waiting a hr just to melt enough iron for a small part that alone 1/2 a bottle of gas!

xlchainsaw wrote:
wonderful vid. from what you have shown and some fine tuning i think a thermite powered furnace is the way to go especially if it had a crucible in it. it sure beats waiting a hr just to melt enough iron for a small part that alone 1/2 a bottle of gas!
Yes, you are right!
You get about 45% of the total weight of a charge, as iron. I would stop at about a 12 pound charge. I've done 1, 12 pounder. It's about all you can handle at home, without some serious industrial size equipment. That means you are limited to about 5 pound ingots

Let me know if you need more info. I'll share what I got...

i will start by mixing a bit up . i think it time for me to slowly build up experience handling the stuff. im taking it for granted that you have made and used copper thermite!!but one question we asked here. can brass be made into a thermite???a couple of members here have been playing with their furnaces and have suffered melt down!! they think as i do that they hit the "thermite" button accidently because extra high heat and sparks were noted above usual.both have been melting brass and aluminium regulary.they think as i do that some brass was in the bottom of the fire and some aluminium dripped on it and mixed .....coupled with high heat ....ignition!!!!!!!??????