Mold Making - Mass Casting Complex Parts (with a Parting Line)


Introduction: Mold Making - Mass Casting Complex Parts (with a Parting Line)

When mass casting a part without a flat side, you must create a two-part mold. We create a two-part silicone rubber mold with a clean parting line and then cast the part with Repro.

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    use this mold to make a wax copy of your part then use the wax copy in a sand mold. the hot aluminum boils away the wax and takes its shape

    I think you're supposed to pour plaster to make metal castings, this plastic might melt. but you should be able to use same process, just swap out the polymer with plaster

    Can you make a mold of a whole tree of a model?

    Very cool. I have a question though, can you pour liquid plastic into these molds and harden the same way?

    Nice clear overview of the moldmaking and casting process! I'd like to see it with an even more complex shape, one that didn't lend itself easily to the wood baseplate method. Also, I can't be the only one who heard "spray-on vaseilne" and immediately started thinking up prank uses for that stuff. To be in high school again!

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    well now your not

    the plywood base could be replaced withclay, which is malleable and secure. Great instructable. 5*

    Every time I've tried to order products from this company I get nothing but silence.

    using plasticine instead of milled wood also kinda works for the parting line. just poke dimples in it for the locking mechanism. More ghetto but less time consuming. I love that fact you are wearing lab coats in all of this. It reeks of SCIENCE!!

    wow, neat videos... posting a lot of stuff eh?