Thread: Sand casting?
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Unread 24-06-2009, 18:23
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Re: Sand casting?

Quote:
Originally Posted by Wayne C. View Post
you might try ceramic shell or some sort of investment casting instead of sand. If you can make a wax model of what you want or a rubber mold of the original you can fill with wax you may be able to do the burnout in a ceramics kiln or similar oven.

What kind of equipment do you have?

Erik is right that the undercuts that the center around the axis will be a real bear to cast. How big is this hub? The thinness of the spokes will also be an issue requiring pretty hot metal.

Of course if you are casting ferric stuff expect oxidation to be an issue. Any time you cast a very reactive metal (iron, copper etc) it is a good idea to cover the crucible with an inert gas like Argon.

YEARS ago I worked as a caster with precious metals and some brass/bronze. I can see how I would make this with the equipment I had then but all that was investment based and not too improvised.

Hope it gives some ideas
My boss seems to think that this part is either too big for investment casting or that the process is too cost prohibitive to be viable for the number of these we'll need.

Ultimately, they'll be produced for us by a vendor, so it's not a matter of equipment, just a matter of design. I'm trying to faithfully recreate this part, for the most part, but I'm trying to be cognizant of any changes I make and how they'll affect the casting process.

The undercut inside the sphere is the most challenging part, I think. We're not entirely sure why it was manufactured that way in the first place. We considered that it might have been to keep the wall thickness as uniform as reasonably possible, but that sort of effort was not made anywhere else on the casting.

Edited to add: The part is, at its widest, about 20" in diameter and about 12" tall.
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Last edited by Madison : 24-06-2009 at 18:29.