Make a ceramic slab with a rolling pin and shims. Take 2 fingers away from the edge of the object and cut a circle (use the compass).
Place the object in the middle, wrap a plastic sheet around it with adhesive tape and seal the base with more ceramic.
Prepared and cast the plaster, place a wooden slab over the mould and wait 30/40 minutes for the plaster to react.
Once the plastic sheet has been removed, flatten the base of the mould to be able to turn it with a flat and stable base.
Once you have turned the mould and removed the initial ceramic circle placed at the base, make holes in the thickness of the plaster to create the joint for the second part of the mould (the object in the photo used to make these holes is beautiful; note the coin at its end). Cover the wires with a truncated ceramic cone so that you have in the centre of the mould the hole from which the liquid ceramic will be poured.
Wrap the mould once again with a plastic sheet to make the second casting of plaster.
Open the mould by inserting water inside so that it helps to draw the object out.
This whole process was done on the last day of December when the workshops were open (13.12.2019).
Today (06.01.2020) I went back to the workshop to pour ceramic into my mould for the first time.
Once the mould is completely dry, it was closed with a lever-locking strap that locks the two parts perfectly.
I filled two pitchers with liquid ceramic and poured them into the mould until it was completely filled.
Once passed 30 minutes in which the mold has absorbed water (as we can see in the picture) turn the mold upside down and leave it to dry for at least an hour.
At this point we just have to open the mould. Before doing so we turned it over to try to separate the ceramic walls from the plaster.
Once we had opened the upper part of the mould we cut the cone created by the sprue and, putting a wooden slab underneath, we turned it upside down.
The siren came out immediately and the details of the inscriptions are all there.
Now we have to wait for it to dry before we can cook it.
I had already done the whole process of making this kind of molds several times but I wanted to get Tas to help me to get new advice from a professional. Learning his process was really useful, he showed me tools that I had never used before and removed doubts about many steps I was doing roughly.