making a (more) permanent mold from cement/concrete for aluminum castings?
I've been looking into aluminum casting for a while now (done it once or twice with different "furnaces")
Now I'm reading alot about lost foam casting (sounds interessting too)
But I was thinking; do you think (/have experience) that I could make some kind of "permanent" mold out of some kind of cement/ concrete/ fireclay mixture for casting similar pieces several times??
I was thinking, when you make the furnace(s) you make a cement/ concrete/ fireclay mixture that can withstand the temperature, so shouldn't it be able to withstand the temperature of the aluminum being poured into it also?
(and therefor be able to make the mold out of)
- I was thinking to use a special type of cement ment for use around a fireplace.
What do you know/ think of the idea?
- and also; is there any (other) cheap/ "easy" way to make permanent molds for several similar castings? (at home/ the backyard)
PS. not important but I've made/ used a coal fired furnace, a gas (butane) fired furnace and now I'm about to build an electrical furnace (for the sake of expence and time of heating up)... I'm trying to make some casting sand/ green sand, but the ingredients looks to be rather difficult for me to gather (In Denmark Europe)