metal casting.. tricky question. molding/casting a 2 sided coin

ok...

been doodling (only thing i can really do while on percocet :lol) and i have an idea for a coin i would like to replicate. i have some pot metal, and i have some slight talent, and can get some silicone.

only problem i am having is how in the world do i do a coin with both sides? a one sided coin is easy, but the 2 sided looks like its going to be a pain. i was thinking of a small "vent" hole to let the metal go in, and another "air" hole and just sorta snap the excess metal off when i demold it. that might be kinda hard to go since this coin is going to be a little thin. not the giant 3/16" wide that i think molten metal needs to flow properly.

so.... any ideas on this? im a little lost. i know i am probably missing something obvious but like i said, doodling and cant wrap my head around this one.

i do plan to sculpt the coin, or maybe recast a coin that i modify with a slightly different "back". and no, this isnt a POTC coin or any movie prop related coin. its from a book. just wanna make that clear.

any advice is welcome
chris

For a coin you need to spin cast it.
here is a link so you can see what the procedure is
http://www.tekcast.com/sixeasy.htm

This is a moderate priced unit. However you can make your own spin caster if you have the tools and parts. The spin caster uses a vulcanized mold but I have seen it done with RTV. There is also a putty called Quick-Sil http://cgi.ebay.com/Quick-Sil-Mold-Making-...1QQcmdZViewItem

Becareful of spin casting. It litterally will shoot you with hot lead.

you dont HAVE to spin cast it... i do a lost wax for my wolf coins, i add a small pour sprue to the part and pour rubber around it, then cut it free, you can then make wax casting, OR you can get a high temp rubber and pour pewter directly into the rubber itself... you can buy a less than expensive pewter pot on ebay and then have fun...

i guessing here but could you mould the coin with a over pour flange then pour the metal in the open faced mould and then press the top of the mould over that?

For what your suggesting the lost-wax process is best as you can attach several sprue's to your coin as you both want to be able to pour and vent to allow the air out as you pour the hot metal in , filing and trimming once cold with a fine Dremmel works best for me , I've made a lot of replica medals this way.

For what you want to do - lost cast wax is the best and most effective to use, I've produced dubloons and other items medals in exactly the same way

I have a friend that does those. He uses a sand mold and makes a small trench to pour the metal into.

FYI - I did some fake coins for my brother's church a few years ago. The coins were modeled on coins from the time of the birth of ******. They were extremely thin and cast just fine using OR-8 lead free pewter in a hand carved soapstone mold (less then 1/8 inch in thickness, just a little over a dime's thickness).

Tim/Theatrix
Welcome to Pewtering.Com

I've already gotten the coins finished up, and don't really need to do anything else with the project, BUT please feel free to continue the advice train.

It's helpful, and I am sure other people will be able to use the advice you guys have.

It's one of the reasons I love this board

Thanks!!
Chris