Darth Vader Medalion Casting

I wanted to make a medaillon for a friends mom cause she really LOVES Star Wars
and especially Dart Vader.

For my Darth Vader medallion ( to get a necklacepiece) I used a piece of isolationfoam from my attic.

I used a hotwirefoamcutter to get the rough shape
and an X-actoknive to smooth the edges.

I used a stencils I found on the internet
and drawn it on a piece of paper which I then glued on the piece of foam.

To get the details from the stencils to be shown on the foam I just traced the lines with a pencil.

After tracing every line of the stencil
I took the paper away and carved some parts deeper with a sharp knive.
So I could create some depth and texture.

I wanted to see if putting my piece of foam in some plaster and casting it that way if it would work.

I mainly did this because I wasn't sure if I used sand that all details would be shown that nicely...


I casted it with my homemade foundry (I don't have any pictures of that because I forgot)
but it is just made from an old steel pot with a pipe for extra airsupply with a hairdryer
and as fuel I used charcoal.

As you can see casting with foam and investment doesn't work.

I think it's because I forgot to put airvents in the plaster and while the foam wa burning away the hot gasses didn't have room to expand and that's why it didn't completely cast that well.

At the time when I made the investments I made 2 others but I am affraid that when I would bust them out of the plaster they would get destroyed.
So I am going to try and burn the foam as best as I can, and try casting them.

the other two I made is a bust of Saurons helmet and a falconhead (because my totem in the Scouting is Falcon)


I hope you guys enjoyed my instructable and my explanation why I failed.
Sorry if my english wasn't that good (it's not my native tongue)