This was my first attempt at making a mould. It was pretty cool and I learned a lot.
Special thanks to my brother for the high octane action shots.
So first we start with our nice mould box. With 20/20 hindsight I now realize I could have gotten away with maybe 2/3 of the silicone if I made the box a bit smaller.
Then sealed it all up (not enough!) Next I poured water into the mould taking note of how much, to calculate how much silicone rubber it would take. According to my reading, silicone and water are roughly equivalent weight.
And thank Christ I did because then all the water leaked out!
Left the mould to dry out over night. Silicone and water are not good friends.
Round two of sealing switched to the NSP Chevants clay it’s much stickier and did a better job. Oh, plus 4 more sticks of hot glue! All set for moulding! (Hopefully)
I’m using Pinky Sil silicone rubber – you just mix the two parts by weight – in this case about 900ml.
I’ve been hoarding yogurt pots for this occasion.
My mixing pots where not big enough for the amount of silicone, so I made up two batches. This might have contributed to the air bubbles on the back of the mould.
Tearing apart the mould box maybe the most satisfying part of the project.
Next step – cutting the mould in two.
I had to remove the sculpt first. I had super glued the stand I had sculpted it on to the base (which I wouldn’t do again).
I had to pull it off. It was quite painful 🙁
But there’s no turning back now, so I started cutting. This would have been easier with a second pair of hands but I still only have two. Jeez!
I made do by wedging the lid of an exacto knife in the gap.
As you can see the front has came out pretty damn good, the second half however has a lot of air bubbles, again I think this was to do with how I laid out the mould.
And I suppose if you’re going to have air bubbles at least they’re on the back and the two major ones are on the base, so we’ll call that a win and won’t do that again.
Spent twenty minutes cleaning tiny bits of clay out of the mould with a toothpick (and I should have spent longer).
Then cut some channels from the arms – I don’t think they really did anything but good practice.
I tested with water again for the amounts and again left to dry over night, resin also won’t cure properly if there’s any water left in the mould.
Ready for casting!
Casting with easy cure resin about 210 ml.
The resin had a two minute pot life which made mixing and pouring stressful.
Let sit twenty minutes the de-moulded it.
Well. So that looks kinda like honey comb.
But the resin has flowed all the way to the tip of the helmet and to both shoulders, so I’m pretty pleased with that for my first time. It looks like there was just a lot of air trapped in the resin.
The silicone picked up terrific detail and with no real mould line to speak of, so I’m very happy with that.
I’ve started to fill the holes and get it ready for painting.
Thanks for reading!