Introduction: Homemade (Oil-based) Modelling Clay

I enjoy stop motion animation, so was inspired to attempt making my own plasticine.

It's not exactly cheaper than buying the factory made plasticine, but its fun for a rainy afternoon so the kids can stay entertained.

My recipe is experimental, so I'll attempt to keep improving it. These measurements will give a soft textured plasticine modelling clay.

Step 1: Collect Your Ingredients

As this recipe was rather experimental - I kept adding ingredients until the texture of the plasticine seemed malleable and firm enough to sculpt.



The recipe was based on Wikipedia's description of the history of plasticine - calcium carbonate, wax, petroleum and mineral oil. 

The closest thing to calcium carbonate I have is a material to make fillers for tiles and concrete and also called hydrated lime - the stuff used to make your own paint.  Some recipes online recommend paraffin wax. Others say this will result in a crumbly mix. Also there are toxic fumes to consider when remelting paraffin wax. On the other hand beeswax is quite safe.

Calcium carbonate / calcium hydroxide powder is available at any hardware store. Wear a dust mask and eye protection for safety when handling lime powder / sand - also during cooking is advisable. Fumes rise up when mixing calcium carbonate with water and begins to heat up and bubble when away from the stove. (Can damage the lungs and respiratory system if inhaled. I was coughing for weeks).

("Lime is an alkaline substance and therefore, caustic. You need to wear gloves, long sleeves, and eye protection to avoid the possibility of lime burns." - Janine Bjornson (Green Home Natural Building Plaster)



Beeswax has the advantage of being remelted over and over, so I decided on experimenting with beeswax, that way I can constantly adjust my recipe until I'm happy with the texture. It has a pleasant fragrance as well.

So after a bit of mixing and adjusting -  these were the final measurements to make a cup of cream-coloured  plasticine.

(You need two old pots for melting everything - not to be used with food ever again)

Ingredients

1 A4 sheet 100% beeswax (70g-100g)
6 teaspoons mineral oil (baby oil)
optional - 1 tablespoon liquid paraffin
4 tablespoons petroleum jelly (vaseline)
2 tablespoons 100% coconut oil / linseed oil
3/4 cup limestone powder (calcium hydroxide ie. hydrated lime)


Purpose of ingredients
According to Wikipedia, the original recipe by William Harbutt in 1897 is kept secret.  But then lists the ingedients - "Plasticine is composed of calcium salts (principally calcium carbonate), petroleum jelly, and long-chain aliphatic acids (principally stearic acid)."
Beeswax is the binder and helps the dry and oily ingredients to stick together.
Coconut oil and linseed oil both contain 8% stearic acid which helps the stay smooth in a way the mineral oils and petroleum oils do not
Liquid paraffin - preservative (optional I do not personally use this in this recipe, because of the fumes, I believe beeswax to be safer)
Limestone powder gives bulk and body to clay

Step 2: Melt Ingredients

Ingredients

1 A4 sheet 100% beeswax (100g)
6 teaspoons mineral oil (baby oil)
3 tablespoons petroleum jelly (vaseline)
2 tablespoons coconut oil / linseed oil
1/2 cup limestone powder

Place some water in the larger pot.  Bring to boil.

Place the smaller pot inside.

Break beeswax into smaller pieces.  Melt at medium heat. 

Step 3: Add Limestone Powder and Oils

Stir in 3/4 cup of limestone powder.  Stir until all lumps are smoothed.

Add baby oil, coconut oil / linseed oil and petroleum jelly last 30 seconds of stirring well before turning off heat. 

Quickly pour onto trays / plates lined with aluminum foil. 

It will harden quickly - in around 10 minutes.  Check the texture by rolling with your hands.

If the texture is too firm place modelling clay into double pots again, reheat on low and add more lime powder, petroleum jelly and mineral oil.  Cool again. 

TROUBLESHOOTING Texture Problems


Too crumbly - Increase the amount of wax and oils to increase stickiness and soften texture of overall mix. The mixture should become more malleable and thinly rolled sections will no longer fall to pieces.

Too firm - Add more oils and limestone powder.  It should become more sticky. If the ratio of beeswax is larger compared to the other ingredients, the modelling clay will be quite firm. This is perfect for finer sculpting.

PS. Its possible to experiment with turpentine and linseed oil for softening or thickening your mixture - but away from the stove for saftey.
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Watch this instructable as a 1 minute MOVIE (for visual learners who prefer watching instructables to reading them)

Step 4: Colour You Plasticine

Ideas for colouring your modelling clay -
Add tumeric for bright yellow.
In the pictures above I added 1 tablespoon of dried colour pigments to my mix
You could experiment with oil paints for colouring.
Store in an air tight container.


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It's interesting to note that oil paints contain the same ingredients in this experimental plasticine recipe with the exception of whiting or lime powder (calcium carbonate).

Step 5: What You Can Do With Plasticine?

Check out this instructable for modelling tips which will help greatly with creativity.
https://www.instructables.com/id/How-to-draw-anything/

Animation, casting, stop-motion, jewelry, plasticine paint-by-numbers gifts - possibilities with plasticine are endless!
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Here's a quick tip on warming a cold lump of your modelling clay easily.
1. Tear clay into small sections. Wrap in plastic wrap.
2. Place boiling water inside hot water bottle. Cover with plastic bag.
3. Place small clay pieces around plastic bag. Cover again with another plastic bag and wrap tightly with towel or other material.
4. The clay lumps will soften within 5 minutes.