Final Cast

Casting

Silicone

Fibreglassing

First I added a layer of gel coat until it was completely dry(took around 40 mins -1hr 30). This is gel coat with 2% catalyst. Then another gel coat with fibreglass sprinkles in it so that the fiberglass matting will cling better. I waited until it was sticky but the gel didn't come off on my glove (took about 30mins, but can take longer on a cold day). Then I painted resin with 2% catalyst onto fibreglass matting onto my piece using a paint brush to dab into the small spaces.

 

 
 Once both sides are dry, there's a loooooong process of getting the clay off the fibre glass mold. But it is very satisfying when it is clean.

 

Then so that the two sides of the mold will fit together, i sanded then edges and drilled holes through both sides so that i can but a nut and bolt through later to keep it together.

Molding

Silicone mold supported by a fibreglass jacket.
I made this jig below, so that I could roll out slabs of clay in the same thickness. Then I added them on top of the cling film and smoothed it all together. But I didn't want to push too hard, so that I didn't ruin the sculpt below.

Here I have added keys and along the split line, on the sides and around the bottom edge so that the silicone will fit nicely into the fiberglass mold and the detail will line up properly.









Paint the edge with blue PVA, so that the fibreglass won't stick to the wooden board

I have added a clay funnel that will later be used as a pouring hole for the silicone.







Then I added vac formed plastic to create a shim. There were a lot of gaps so I simply filled them in with sellotape

                                

Preparing the sculpt to Mold

I made a wooden back for the head to lie against and for the flange to be made on. Then I covered it in cling film.



 

I had never made a mold before this, So I have taken lots of photos so that I can use it next time. I am making a matrix mold.

Final Sculpt before molding and casting

I have taken a photo of the sculpt before I mold and cast it, in case anything bad happens in the process, so that I still have evidence that I have done it.