The Cherubs part II

5 March, 2012 – 11:30 am


The next stage was to cast the clay models in plaster.

I separated the cherubs in order to cast them more easily. I scored a line to distinguish between the front and back-this allows me to see where the two halves will be for casting. I pushed in brass metal shim along this line to give a barrier against the plaster.

The first layer of plaster is a very thin coloured layer-the reason for this will become apparent later.

I applyed this first layer to both halves of each cherub, making sure to completely cover the features and not to trap any air. I allowed this to dry before applying the second and final layer.

It is very important to have a good knowledge of this process and the drying times of plaster, it ‘goes off’ all of a sudden and this is the best time to layer on the plaster.
I was very fortunate that my Grammar school had a 3D department where I learnt all about working with clay and plaster. My degree in sculpture focused on portrait and figurative modelling in clay and plaster, so I have a good deal of experience with these processes.

If you would like to learn more in a hands on environment please get in touch via my contact me page

Once the outside of both cherubs were completely covered in plaster-except the centre line I allowed the plaster to dry out. The centre line now gives me an in and very carefully I prise the halves appart. The clay inside must be dug out completely-but carefully in order not to scratch the mould.

Once the inside is completely clean, I brush a barrier on the inside as I now start to pour in the plaster , carefully so as not to trap any air. The liquid plaster will suddenly ‘go off’ this is when the ability to ice a cake comes in handy! Using a spatula I smeared the plaster being careful not to get any on the joint.

Once all halves are done I put them together lining up the edges so the final cast will be a perfect replica of the clay model. I used hessian sacking and more plaster to bond the two halves together. I then poured some plaster inside to join the two halves on the inside. Don’t fill up the inside, it isn’t necessary and wastes plaster.

You may have noticed that the older of the two cherubs didn’t have it’s wings-this is because it would have been too dificult to cast it with them on. I put them on once the casting was completed.

Once the casts had dried out completely I was able to start chiselling off the outer skin of plaster. The thin layer of coloured plaster now comes into use, it gives me an indication of how close I am to the actual cast.

Well you can now see the finished casts. If I want to change any detail or add any more plaster I can.

Next stage is the sawing of the actual stone 🙂



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