How to Use Plaster of Paris

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How to Use Plaster of Paris

Plaster of Paris is a wonderful art medium that is easy to use for creating things from moulds and free form artwork. It's a powdered substance that becomes a pourable mixture when combined with water. The mixture is light and thin enough that it fills in even the finest details on the mould. When it dries, the resulting piece is smooth with fine details. The surface receives paint well, allowing the artist to create an infinite number of different looks from the same mould, making it very versatile and a great way to encourage and use creativity.

Cautions When Using Plaster of Paris

Plaster of Paris hardens quickly and produces heat while curing. It is important to not immerse hands or body parts in the plaster in a way that can trap them when it dries. Do not use hands to mix it. Also, before mixed with water, the fine plaster particles easily float on the air, so take caution to minimise this and do not breathe in the dust.

Step 1: Prepare

A great first step that ensures success while using Plaster of Paris is to take measures to prepare the area and tools before beginning the mixing process.

* Cover the surrounding area to protect it from the Plaster of Paris.

* Be sure that the mould, cast, or whatever the plaster is poured onto is clean of any dust and debris.

* Prepare a container to mix the Plaster of Paris in. A bowl works fine, although a container with a pour spout makes some jobs easier. It should be clean of any residue.

* Have all the necessary ingredients and tools on hand. This includes the Plaster of Paris, water, a measuring jug, mixing container, and stir stick.

Of course, different projects may require additional steps or supplies. Because it hardens so quickly, it is important to think the process through beforehand and make sure that all necessary tools are handy and all surfaces are prepared.

Step 2: Combining the Plaster of Paris with Water

It's important to follow the directions on the package, if there are any. Generally, the proportion of Plaster of Paris to water is a 2:1 ratio, with two parts Plaster of Paris to every one part water. Add the water to the container first, and then slowly add the Plaster of Paris, sprinkling it across the entire surface and allowing it to settle before adding more. Air bubbles should rise.

Continue adding the plaster until the occasional, small, almost dry island of plaster stays on the surface. These should appear when about two parts Plaster of Paris have been added, but the water temperature and the brand of plaster may affect that.

Step 3: Mixing the Plaster of Paris

Avoid stirring the Plaster of Paris any more than necessary. It is important to remove all air bubbles from the mixture, and over mixing introduces more air. These bubbles can show up in the project and may detract from its looks.

While adding the Plaster of Paris to the container, air bubbles should rise. They should continue to rise afterwards, and vibrating the container or tapping the sides of it encourages this. Once most of the air is out, use a stir stick or disposable spoon to gently mix the Plaster of Paris to ensure its smooth, even texture. Stir it as little as possible.

Step 4: Pouring the Plaster of Paris

Letting the mixture sit for a moment or two allows the plaster to absorb the water and release all the air, giving it an even consistency. Pour it slowly, allowing it to spread out and cover all the areas and details of the mould. Add it a little at a time, letting any residual air bubbles escape and letting the mixture cover evenly.

After the mould is full, take care to smooth out the surface of the Plaster of Paris, evening it out and filling any empty spaces that may have appeared as the air escaped. It dries and hardens very quickly. It is possible to start working with the project within 30 minutes to an hour after pouring. Letting it sit longer, though, allows it to thoroughly set and dry. Therefore, whenever possible, let the Plaster of Paris mixture sit overnight or even over several days before handling.

How to Buy Plaster of Paris on eBay

Plaster of Paris is a great art medium to work with because it is easy for anyone to use successfully, it produces great results, and, best of all, it is very inexpensive to purchase from art supply and craft stores, as well as from online merchants. All art and craft supplies are very affordably priced on eBay, and shopping there takes away the need to leave the craft room or art studio.

When shopping for Plaster of Paris on eBay, pay close attention to how much is included in the purchase. It is available in a number of different size packages, including 1kg, 5kg, and 25kg. Also, check out the seller's other items. It is possible to ship more than one item together if ordering from the same seller, which can make it even more affordable to purchase extra Plaster of Paris or the moulds to pour it into.

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