Please excuse the simplicity of this video, this is my very first attempt at making a video ever, so it’s a little rough. I wanted to show how easy it is to cast small details like iconography in Green Stuff using Blu-Stuff as a mold. I started with some icons I sculpted myself for a Minotaurs Space Marine chapter that were sculpted for a client building a Badab War force. There are three sizes of icon, one for each, power armour, terminator armour and vehicle. I made the mold by mixing two equal sized lumps of grey and blue parts of the Blu-Stuff putty and splodged (technical term) it in place. Because it cures so quickly it needs to be applied to the surface you are casting after about 1 minute from the start of mixing, it is however very soft (more so than other silicone putties) and mixes incredibly easily.
Because of the time sensitive nature of this part I opted to not to try to video that part. One of the best things about Blu-Stuff is that is doesn’t stick to anything. First mix greenstuff in a soft mix of 2:1 yellow to blue. Start by pressing it into the mold with wet tool. Because the GS doesn’t stick to the mold you have to keep the tool well lubricated at all times else you’ll end up pulling it out the mold as you try to press it in.
As you fill the mold, try to avoid trapping air between the Green Stuff and mold. If you see little lumps appear on the surface of the Green Stuff that means there is trapped air underneath, so it is best to start over. As you work, the mold will often have too much Green Stuff in it, carefully wipe away the excess around the edges. It doesn’t matter if there is some left as it can be easily trimmed later, very much like flash on normal castings.
I tend to keep this excess GS to one side to help me gauge when it will be ready to remove from the mold, as I can poke it and tell how much it has cured. I generally wait one to one and a half hours before carefully removing the GS from the mold with a scalpel and transplanting it onto (in this case) the correct shoulder pad. This is very much like applying a transfer onto a shoulder pad. It can be moved and is still tacky enough to stick to the plastic but can be done (if you are careful) without damaging the detail.
Another example of masters and molds for Space Marine chapter iconography.