Make a Mould of Your Thumb With PVA and Cornstarch

I was looking for a way to make a mould of my thumb to create plaster thumbtacks as a fun afternoon projects for kids. I had limited supplies at home and no way to get anything delivered on time, so I used this old recipe for home made air dry clay using only two ingredients - PVA glue and cornstarch.

PVA glue

cornstarch

plaster for casting pva

paint

small magnets or thumbtacks

strong glue

Mix one part glue and two parts cornstarch. Have more cornstarch at hand in case you need it later. Mix it in a bowl, then knead it on a flat surface.

You have to continue kneading and adding more cornflour, even if it feels like it's too dry. It might feel dry, but it won't be ready until it holds its shape instead of spreading. Pinch a portion of the clay with your fingers, if that indent doesn't change- you are good to go. If it spreads out- you need to add more cornflour and knead it more.

Place clay it in separate small, separate containers lined with cling film (for easy removal). Coat your finger with a thin layer of vaseline (or oil) and press your thumb all the way into the clay and gently pull out. Immediately after that, mix a small amount of thin plaster and pour it in. Move it around to distribute it evenly and leave it to set for 1 hour.

After one hour, use cling film to pull the whole clay block out of the container and use your fingers to remove thumbs. Gently clean them with your fingers, to uncover the details and leave it aside to dry fully. Plaster will be too wet to sand yet. You can reuse the 'clay' and create more thumbs, it will still be wet enough for 1-2 tries.

After all your thumbs are out of the clay and dried completely, use sanding paper to gently remove any imperfections. Use a knife to carve small holes for magnets or thumbtacks. Dust the particles of plaster with a stiff brush.

Use acrylic paint to colour the thumbs and nails.Seal with a sealer.

Use strong glue to add small magnets or actual thumbtacks.