I brought an 'Apple of Eden' Assassins Creed - Origins replica and was pretty disappointed with the look so I thought 'I've got access to silicone rubber and casting resin - I'll make my own!'
The following step by step guide of how I made my own Apple of Eden using a simple rotocasting by hand technique, will I hope inspire you to try out this great technique.
By creating a split silicone rubber mould, casting a replica metallic piece using metal powder and finishing the piece to bring out the metallic effect. I created my 3D hollow sphere using the rotocasting by hand technique which meant that I didn't need a rotocasting machine and I used a much smaller amount of resin, keeping costs to a minimum and trying and testing a technique which I have no doubt can be used for future projects.
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Step 1: Materials
Silicone Rubber and Catalyst - I used Easy Composites CS25 Silicone Rubber and Catalyst
Fast Casting Polyurethane Resin - I used Xencast® P2
Mixing Pots and Sticks
Something to make a container - I used Signboard
Cutting Board, Craft Knife, Ruler, Pen
Glue Gun and Tape
Black Spray Paint
Prepare the work area - cover work surface and wear protective clothing.
Step 2: Creating a Split Mould - Bottom Half
- Using modelling clay I embedded the original sphere up to the halfway point.
- Then I smoothed the surface of the modelling clay.
- I keyed the surface with an acorn nut and created a snug container around the clay.
- Next I weighed out the correct amount of silicone and catalyst and mixed them together until I achieved a consistent colour - mixing steadily to minimise air bubbles.
- Then I poured it over the original by approximately 5mm and left it to cure (as per the manufacturers instructions).
Step 3: Creating a Split Mould - Top Half
- When the silicone had cured, I removed the container and removed the modelling clay carefully - making sure not to move the original.
- Then I rebuilt the container around the bottom part of the mould.
- Next I brushed petroleum jelly on the silicone to stop the two parts of the mould sticking together.
- Then I repeated the silicone process as before and poured over the part to create the top part and left it to cure.
- Once it was cured, I opened the mould and removed the original.
Step 4: Casting the Metallic Apple of Eden
- First I mixed the metal powder into a small amount of resin (Part A) to make a thick/slushy mixture, for this sphere i used bronze.
- Next I mixed an equal amount of Part B resin into Part A and brushed on to both parts of the mould.
- This resin cures really quickly (starting to cure in around 3 minutes), so I had to work fast.
- Then I mixed up a lighter resin and metal powder mixture and poured into one half of the mould.
Step 5: Rotocasting
- I quickly sealed the mould using tape all around.
- Next I hand rotated or rotocasted the mould until the resin was well on the way to curing - the Xencast® P2 resin that I used cures fully in under 30 minutes, but the initial cure is slowed down by the addition of metal powder so for this particular sphere with bronze powder I rotated for at least 10 minutes to be on the safe side - I set myself a timer and did a little work out!
- When I was confident it had cured enough to stop rotating I left it to cure for the remainder of the 30 minutes.
Step 6: Revealing the Metallic Effects
- When I demoulded the sphere I noticed that it didn't look metallic at all - so I needed to uncover the metallic effect. It looks like this because a thin layer of resin forms over the metal particles.
- So I abraded the surface using sand paper, steel wool and polish.
- Then I used black spray paint and when it was dry I used steel wool to bring out the detail, contrast and highlights.
- It looks brilliant and because of the bronze powder feels cool to touch and has a good weight to it unlike the original shop brought plastic sphere.
Step 7: Apples of Eden - Finished!
You can create different effects using different metal powders- I rotocasted in plain resin too which I rotated for much less time and also used copper which gave a different metallic result.
The best discovery from this project for me was not just achieving a result like this - but equally finding a way to rotocast by hand a hollow 3D shape with no pour holes, vents and very little work to do to the finished piece - (except the metallic finishing effects), meaning that the costs are kept down and expensive additional equipment wasn't required.
I think that by using this technique and a fast cast resin like the P2 you could create decorations, props, other 3D hollow shapes and other larger scale projects.
Once you have created the Silicone Mould (top and bottom) - you are realistically looking at a casting and finishing time of around 1 hour or less per piece!