Ideal for school projects, hobbyists or artists.
Mixing Directions: We suggest approximately 1 part water to 2 parts plaster, however this will vary with temperature of water used and prevailing weather conditions.
Water should always be added to the mixing tray first then sprinkle or sift plaster into the water in small quantities and gently mix with spatula.
Tap sides to vibrate and release air bubbles.
When mixture is a smooth, even consistency and a uniform light grey color it is ready to pour into mould.
Never use bare hands to mix or stir plaster.
Why you should buy plaster of Paris
For artistic purposes, plaster of Paris is the ideal type of plaster. Some people think that plaster is plaster, and that “plaster of Paris” is just a fancy title without any special meaning.
The truth is that plaster of Paris is specially formulated, and the formulation gives the plaster unique properties that make it highly suited to art and also certain other purposes.
The important ingredient in plaster of Paris is gypsum (in fact the correct name for plaster of Paris is actually gypsum plaster). The gypsum is super heated, which changes the molecular structure. The resulting powder can be turned back into gypsum by adding water, and that is why the plaster hardens to a firm surface.
However, the interesting feature of this reconstituted gypsum that makes it so suitable as an art material is that even after hardening, the surface is still very workable. You can sand it, sculpt it, etch it, paint it… it’s wonderfully versatile and can be used in so many different ways.
How to make coloured plaster of Paris
Everyone knows that plaster of Paris is very white. That’s a property of the gypsum. However, if you mix the plaster powder with tempera paint powder, it will create beautifully tinted plaster, which opens up even more possibilities.
You will need to be careful, of course, because by adding the paint powder, you are actually introducing what is called an adulterant. This affects the chemical formula of the resulting plaster and can affect the properties of the end product. It’s all about the ratio.
You want to be aiming for a ratio of about 5 parts plaster powder to 1 part paint powder (5:1 ratio), and you can experiment with minor adjustments to get the ultimate balance of vivid colour to product strength.