Prosthetics - Running the silicone flat moulds and latex ears!

Flat Moulds:

This was the first time the student had attempted running a flat mould. This mould had been made to add some extra details to the final design. Eject-It spray had been applied before three layers of alcohol based cap-plastic were applied. 20g of silicone was made, 5g of part A and B of platsil gel 10, and 10g of Smiths prosthetic deadener. Multiple issues arose with this first run. The silicone did not fully set, and it seemed that maybe the cap-plastic hadn't been applied thoroughly as the silicone appeared to have bonded to the mould. This did ruin this mould.

Figure 1 - First flat mould after silicone poured in (Brown, J. 2021)

Figure 2 - First flat mould after silicone had set (Brown, J. 2021)

Luckily, the original sculpt was still intact so this was remoulded in silicone.

Figure 3 - New flat mould (Brown, J. 2021)

By this point, the cap-plastic had been changed to the acetone based, after having experimented with the snap moulds. Greater care was also being taken to ensure the entirety of the mould had been coated before the silicone had been poured. This was done in three layers. This mould was now starting to work, and some pieces were finally being created. The silicone had also been changed to PlatSil gel 25 and LV deadener.

Figure 4 - First successful flat mould pieces (Brown, J. 2021)

Figure 5 - First successful flat mould pieces (Brown, J. 2021)

These pieces were coming out really well, however the encapsulator was a little too thick. When blended with acetone, the edge was very stiff and prominent. However, the cap-plastic was now to be applied with an airbrush, which solved the issue of the thickness. 

Figure 6 - Flat moulds done with airbrush cap-plastic (Brown, J. 2021)

Figure 7 - Flat moulds done with airbrush cap-plastic (Brown, J. 2021)

Eye Flat Moulds:

For the new eye flat mould, petroleum jelly was used as a release agent, acetone based cap-plastic was being used, which was applied with an airbrush in 5 - 6 layers at a 1:8 ratio. The clay for this sculpt weighed 12g so this was the starting line for the quantity of silicone. 6g of deadener and 3g each of A and B. As there had been a lot of prior practice, it did not take long to get a good piece from this mould. Special care was taken to ensure the entire mould had been coated in encapsulator, as the student did not want a repeat of the very first flat mould. 

Figure 8 - First and second eye flat mould runs (Brown, J. 2021)

This was run a few times to experiment with the colour, and there were no issues occurring with this mould.

Figure 9 - Final run used for final image (Brown, J. 2021)

Latex Ears:

This process was entirely new to the student. They only had chance to attempt this a couple of times, however a good result was still achieved. Petroleum jelly was applied inside the plaster mould as a release agent, then 5 to 6 layers of liquid latex was applied, ensuring each layer had set before applying the next one. The student found this process to be fairly simple. The main issue that occurred was that the points in the mould would take longer to set than the rest. This resulted in the first piece being de-moulded without the pointed details.

Figure 10 - First run of latex ears (Brown, J. 2021)

Figure 11 - First run of latex ears (Brown, J. 2021)

This was attempted again, this time a hairdryer was used to help make sure the latex had fully set inside the mould. 

Figure 12 - Second run of latex ears still inside the mould (Brown, J. 2021)

This run had worked and did produce a set of latex ears.

Figure 13 - Successful pair of latex ears used for final image (Brown, J. 2021)

Figure 14 - Successful pair of latex ears used for final image (Brown, J. 2021)

These came out really well, with the exception of the left ear. This was the one that had previously come out incorrectly, and it seems that the liquid latex that hadn't set fully on the first run, wasn't cleaned out well enough and did distort some of the details. They were still usable and were used for the final image. 

Figure 15 - Latex ears used in final image (Brown, J. 2021)

-Jess

Figures:

• Figure 1, 2 - Brown, J. (2021) York College.
• Figure 3, 4 - Brown, J. (2021) Leeds.
• Figure 5 - Brown, J. (2021) York College.
• Figure 6, 7, 8 - Brown, J. (2021) Leeds.
• Figure 9 - Brown, J. (2021) York College.
• Figure 10, 11 - Brown, J. (2021) Leeds.
• Figure 12, 13, 14, 15 - Brown, J. (2021) York College.