Since last week I've fleshed out the armature with plasticine using the drawing of alice as a template...
Next is a close up of the foot to show the plasticine and how it is shaped to fit the shape of the shoe, when the mould is made and the model is cast in silicone, the silicone should fill where the plasticine currently is so that the seam where the feet are attached should be disguised...
The photo below shows the armature once I'd finished covering it in plasticine, though it still needs a little work to smooth out the surface more before making the mould...
I made a box for the mould using cardboard and lining it with parcel tape. I drew around the model and made it shaped around the model rather than square as this will reduce the amount of vinamold I need to use...
The top of the neck will be sticking out of the mould as mentioned in a previous post, this will mean I can trim off excess silicone to make it fit snugly against the head when I glue it on, this will also leave a hole into which the silicone will be poured...
I was a little concerned about using the Vinamold as I didn't have any proper equipment to melt it. I looked online to find any other suggestions for melting but they all sounded a little unsafe, like using a chip fryer, or melting it in the microwave in 10 second bursts. It had been suggested to me to melt it in the oven, but it needs to be melted at a temperature of 140 - 150C and our oven currently doesn't have a working thermostat so the chances of burning the vinamold were pretty high, and burning the vinamold ruins it and reduces the amount of times you can reuse it. In the end I decided to just use a pan, this would allow me to keep a close eye on the vinamold and I could take is off the heat if I thought it was over heating...
The vinamold had arrived in a big slab, so I cut strips off then diced it so that the pieces were smaller and so would hopefully melt easier... it looked a bit like cheese...
I had started by using a larger pan of boiling water and placing the smaller pan over it so that I wasn't heating the pan directly but I couldn't get the vinamold hot enough, so eventually I just used the pan directly on the heat. This actually worked well, I kept a close eye on the vinamold, stirring it and adding the diced pieces a few at a time. When it melted it was a bit like the consistency of custard...
Once all the lumps had melted I poured it into the mould, this will provide a base for the model to lie on when I make the bottom half of the mould. I gave the mould a little shake to level out the vinamold. Once it had cooled and solidified I decided I wanted the base to be a little thicker, so I repeated the process and added a second layer...
Once this has cooled the next step will be to tidy up the model and try and get a smooth finish, then i'll place it on the layer of vinamold and pour more melted vinamold into the box halfway up the side of the model, then i'll brush on a layer of PVA to create a barrier before adding a 2nd, final layer of vinamold. To this layer i'll had some doweling or something similar to ensure that the pieces of the mould line up properly when I put it back together.
Once problem I have found with the vinamold is the bubbles, even when it has first been poured it's thick and removing bubbles on the surface is difficult, I tried to pop a larger one with a craft knife but this didn't work. I could only advise taking care when stirring to avoid trapping air in the mixture. I also don;t know if i had managed to burn it or not, maybe if i had burned it i'd know, but i'm not sure if it discolours or something... might be worth investing in a thermometer.
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