nick  05/07/2005 - 19:10  Painting   
[This article is actually from our forums if you wish to see the original it can be found here]

First of all, I'd like to point out that there is nothing wrong with casting small items like purity seals and icons. There is even a tip in WD301 (UK) about making casts of purity seals, so apparently GW are fine with it as long as it is for personal use only.
Second, I was inspired to do this by Athamas' Tyranid carapace shield, so he deserves credit for this too!

Anyway, here's how I did it.

Items needed:

• A base or another sturdy flat surface to make the mould on. (you’ll need two)
• Green stuff.
• Oil (as a release agent).
• A tool like a modelling knife or a sculpting tool.
• The item(s) you want to cast.

Making the mould

Take a slottabase, it doesn’t matter which variety (square, round) as long as it is closed. Make sure it is large enough to fit the item you are going to make a mould out of. You can also mould multiple items in a single base if the items are small enough (or the base large enough).
For the purpose of this tutorial I will use the smallest of the square bases and will use it to make moulds out of two items: A Dark Angel banner top, and an Inquisitorial seal.
First, fill the base with green stuff and flatten it at the top.



The next step is to take the items you want to cast, and paint them with oil (I use sunflower oil).
Then, carefully press the items to be moulded into the green stuff. Bear in mind that with this method, you can only cast one side of the object.

It helps to get a good impression if you take something flat (like a coin, or another base) to evenly press the item into the green stuff.
After you have pressed the item into the green stuff, wait for it to set properly.



After it has dried carefully remove the items, and if all went well you’ve got yourself a mould!




Casting

Once you’ve got your mould, it is time to start casting.
The first thing you should do, is paint the mould with the oil. This should make it easier to remove the cast once it has set.
Then, prepare some green stuff and roll it into balls or sausages roughly the same size and shape as the recesses in the mould



Then, press the green stuff into the recesses with a flat surface like a coin or a base. It helps to paint that surface with oil to prevent the green stuff from sticking to it and ruining your cast.
Wait for the green stuff to set.



When the green stuff is set, carefully remove the cast from the mould. It should look something like this.



When the cast is removed from the mould, you can cut it from the ‘flash’. I found that curring horizontaly works best. The best way to do this is to lay the cast flat down, and start cutting where the cast meets the ‘flash’. You should now have something that looks like this, the final result!



The possibilities are endless! For example, the angel on my Dreadnought Sarcpohagus is a GS cast.