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Discussion Starter #1 (Edited)
I just noticed this section, I actually joined for the RC section but this iz really cool.

I did a build a year or two ago that I hope is ok to post here. It's 1/64th scale but it's an RC car. I did the build for a micro rc modding site's (bitpimps) end of the year contest. It's all aluminum, based on a 1/64 RC Muscle Machines donor. I cut the chassis and cast selected parts in aluminum. The parts were sand cast from the donor cars parts. I almost burned down the garage with my home made charcoal foundry, and I nearly dumped melted aluminum all over my feet.

It runs, but not well. It was too heavy and the tires are too hard for good traction, but it did kind of drift. Oh, well I guess I should say it ran-- the battery is now dead.

Oh yeah, btw, there are two bodies because the painted one was pitted badly and I had to use filler on a couple of deep sections but I couldn't see throwing it away.

Anyway, here's the highlights:





The body was molded from a diecast and cast in aluminum:


I couldn't decide whether to paint it or polish it so I made two bodies:

 

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Nice work. The foundryfire story is a hoot! I would say that the Cobra ran true to form...not much traction and always in a drift...maybe not for a pro driver but thats how I would drive it:thumbsup:
 

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Discussion Starter #9
Thanks all, I'll have to start doing some diecast projects soon. I'm glad I'm not the only one who can't leave well enough alone.
 

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Outstanding!

I worked in a factory diecasting aluminum and mag and in an iron foundry where we did sand castings. I did a home project sandcasting lead but it was a slightly larger project, not nearly as finely detailed, so I know what you mean about pitting. I used an iron skillet on a gas stove, but lead melts at about half the temp aluminum does.

Keep up the good work. :thumbsup:
 

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Discussion Starter #17
Outstanding!

I worked in a factory diecasting aluminum and mag and in an iron foundry where we did sand castings. I did a home project sandcasting lead but it was a slightly larger project, not nearly as finely detailed, so I know what you mean about pitting. I used an iron skillet on a gas stove, but lead melts at about half the temp aluminum does.
Cool, have you ever worked with tin? Or a tin alloy? I have been wanting to do some more precise casting using latex molds but, of course, they wont take the heat that aluminum requires to melt. I'm wondering how quickly a tin alloy will cool, and if I can make hollow casting with it by pouring the extra out of the mold before it solidifies? If I'm remembering right it melts at around 450F, so it might cool too quickly.

OH, and thanks for the arm welcome everyone.
 

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Cool, have you ever worked with tin? Or a tin alloy? I have been wanting to do some more precise casting using latex molds but, of course, they wont take the heat that aluminum requires to melt. I'm wondering how quickly a tin alloy will cool, and if I can make hollow casting with it by pouring the extra out of the mold before it solidifies? If I'm remembering right it melts at around 450F, so it might cool too quickly.
No, I don't even know where you'd come up w/ tin.

Lead melts around 600F so it's not too hard to get melted down, if you want to try it. Aluminum needs around 1300F to get molten enough to work with. Zinc is lower, but I don't remember the exact temp. Forget magnesium. Maybe you could try melting down a couple old donor cars to see how that works. That's what I'd try first, it may work out or not.

The way a hollow casting is made is by making a cast of both sides and joining the two together, leaving a hollow port known as a gate to pour the metal down through. Both sides are done in a box of sorts, then clamped together so each side lines up to form a cavity of the whole part. The sand was firm enough that they just placed the blank, a car in this instance, on one side then the other side was placed down on top of it to make the cavity. Take it apart and you have both sides of the mold. I doubt you'll get the sand firm enough to do that, but that's how it's done in a foundry. You'll have to do both sides independently most likely. They also make a hollow place for the overpour to come out, if you want to do it right, but you might get away w/o it if you know how much to use. That will also let the air get out easier. After it cools you just cut off the gate and grind/file it down smooth.

I used water, just enough to make the sand stick together enough to form, but water and molten metal don't mix so be very careful or it will pop out and go everywhere. They had a powder they mixed w/ the sand called seacoal that helped the sand to stick together at the foundry.

At the diecast factory we painted our ladels w/ this brown powder stuff (to keep the metal from sticking on the ladel) you mixed w/ water and let dry good before you dipped the metal to pour into the machine.

Good luck. If you have any questions or run into problems let me know and I'll try to help you out
 
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