Next I made the resin master copy. I poured resin into the mould and weighted and left it overnight to set. When I removed the master copy I split the mould and left a small hinge on tinsil underneath to reduce the seamline. The horn had come out really well and picked up all of the detail, it had a few bubbles in it but these were bubbles in the resin and not the mould. The next stage will be a test piece in expanding rigid foam.
The rigid foam piece was really easy to mix and ready to de-mould in around 15 minutes. The first piece had started to kick as I was pouring it into the mould and also overflowed a lot. The foam did not make it all the way to the end of the mould so even though it picked up all of the detail really well it did not work as a full piece. I made another foam piece and only used around half as much and spent only 10 seconds mixing before I started to pour it into the mould. For this piece the foam made it all the way to the end of the mould and overall it was very successful.
I then started to colour the foam failed piece for practice and used pros-aide to varnish it and greasepaint to colour it. When I was happy with the colouring I added some moss to the ridges and I think that this was really effective.
Ok, first post back after deadlines and decided to try to keep the blog going. This blog doesn’t need to be handed in for marking any more so its going to be a bit less formal/academic, I can even put smiley faces in now 😀
Most of the work was still being marked when I got back but I was allowed one of the horns so I straight away got it moulded and cast! I finally decided on a complete silicon mould where I placed the horn in a box and flooded with silicon. Because of the size of the horn I ended up using almost a whole tub of tinsil which is crazy and I’m probably not going to be able to do the other horn in the same way because of the cost of material, but its good to be able to try different ways. I think next time I’m going to try a silicon brush mould with a plaster bandage jacket.
I poured a thin layer of silicon in the box first and allowed it to cure for around 2 hours to make sure I didn’t miss any of the horn in the mould. Once that was cured enough to support the horn I poured in another small amount of silicon and placed the horn on top. I then flooded the box with silicon until the horn was completely submerged. I got rid of as many bubbles as possible and left it to completely cure overnight.
Once the silicon had cured I removed it from the box and started to cut the horn out. De-moulding the horn was a lot harder than I was expecting and because of the way the horn bent back on itself I had to break it in Several places in order to get it all out. Overall though I’m quite confident that the mould has been successful. Next I’m going to create a resin master copy so that I will always have a more robust copy to fall back on.When it comes to removing the master copy from the mould I think that I will have to separate the mould into two parts to get the horn out intact.