Blue Stuff
Blue Stuff - Is it art or science?
You may recall from a previous post, here, I mentioned I had recently purchased a load of second hand Space Marine minis to help boost my Warhammer 40k army. I acquired some bikes, some assault marines, some characters and some other random minis. Most of these were in good condition, although some of the bikes, assault troops and random minis had bits missing. I needed to replace the missing parts to allow all the minis to be successfully assembled.
I took a rummage through my bits box to see if I had anything spare I could use to replace the missing parts. In the bits box I found a few other tactical marines with parts missing, and so began the job of chopping up the models and assembling everything I had to hand.
At the end of this phase, there were still quite a few bikes, and a small number of assault and tactical marines with parts missing. As there were not too many missing parts for each mini, I decided to look online for spares. Wow! I had no idea buying 40K bits online could be so pricey. To just kit out the bikes alone with the minimum to make them functionable would cost somewhere in the region of £60, and so I decided I was going to try and replicate the missing parts instead. I only needed a few of each part, so I thought this was the best option.
I wasn't sure what my best plan was. Silicone moulds and resin pours? Push moulds out of Green Stuff / Milliput? Scratchbuild? I took a look on-line and found a few videos where folk used Blue Stuff (never heard of it) and Milliput to make one off bits for their minis. This looked exactly what I needed and so I took the plunge and bought two packs of Blue Stuff from Green Stuff World (and I picked up a couple packs of Green Stuff for the hell of it), oh and I bought some Yellow / Grey Milliput.
Blue Stuff is a thermoplastic resin; that is to say it melts when hot to become soft and malleable, and hardens when cold to the consistency of a hard rubber. Getting the temperature right for the Blue Stuff, getting the part aligned into the Blue Stuff correctly, and getting the amount of Milliput to fill the mould right were all trial and error. On the tutorial videos it looked simple and I can say now it was anything but, especially for my first few attempts. After several attempts I managed to get the hang of it and I started by making those items of low number requirement first. This way one or two casts and I am done to move onto the next one. The reuseablility factor of Blue Stuff is key here as even if your mould didn't turn out correctly, just re-soften it in hot water and start again.
The results were not too bad, especially considering this was my first attempt at making anything from Blue Stuff / Milliput.
I will continue to play with the Blue Stuff and Milliput as I still need one or two extra bits going forward. The temperature of the hot water to soften the Blue Stuff is important, too hot it sticks to everything including the container, too cold it doesn't shape well. I only made the Milliput in small amounts, generally just what was needed to fill the mould and no more. Mixing Milliput was also trial and error. Whilst it is forgiving in terms of ratios of the Yellow / Grey component to mix together, I found different batches had different curing properties, with some of the bits I made still soft the next day.
The Blue Stuff / Milliput worked out well as it was (reasonably) quick to make the mould, and the short cure time for the Milliput meant I could make several components across a full day. 
Milliput also did not stick to the blue stuff too readily, and scrubbing the Blue Stuff under cold water with a brush soon loosened any flakes of Milliput still adhering to the mould once demoulding was completed. The Milliput was also easy to work with in terms of removing mould lines and generally tidying up the item. This was mostly accomplished with a sharp blade, but a rotary tool and needle file helped out also.
J