The 5 Best Plaster Of Paris [Ranked]
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Are you a DIY enthusiast looking to do things like patching plaster walls without the help of a professional?
If yes, using Plaster of Paris can be a great option to get a beautiful and successful outcome.
This environmentally friendly casting material comes with a lot of advantages over other similar materials.
This has proven to be an amazing material that greatly helps in interior construction because of its properties.
From repairing cracks and holes in plaster walls, ceilings, and drywall to being used for sculpting, modeling, casting forms, and many more – Plaster of Paris can be your go-to option if you want to do a wide range of repairing or crafting related things yourself.
Comparing The Options
- Conventional mixing ratio -- 3 PARTS WATER : 4 PARTS PLASTER
- Perfect Plaster Pottery & Ceramic Casting Material is specially formulated to create the most accurately detailed and high quality casts from your molds
- Great for plaster repairs; hobby molds; and casts
- The professional's choice for casting medium.
Plaster of Paris is a quick setting plaster generally used when someone is looking for a shorter set time.
While this material is perfect for larger repairs, it needs considerable skill so it’s suggested to employ a craftsperson where intricate or significant work is required.
Though Plaster of Paris is a widely used material in the fields of art, architecture etc, you should always buy the product from good online retailers or artist’s supplies shops.
You should also note that this is usually considered a safe material for common use but isn’t regarded as dangerous if worked with responsibly.
However, creating a cast enclosing any part of your body using this material can be potentially very dangerous, especially if the cast’s thickness exceeds a couple of millimeters.
If you are looking to perform some exterior finish, you shouldn’t use the Plaster of Paris as the material can’t be used in a damp finish.
In addition, if you have a tight budget, this may not be the ideal material for you as it’s more expensive compared to cement or cement lime plaster.
Also, if you need some professional help for applying the Plaster of Paris, that cost would be comparatively high.
Plaster of Paris or gypsum plaster is produced by heating powdered gypsum at a very high temperature (Source).
When combined with water, the material forms a paste that will harden within minutes, creating an exothermic reaction that means it warms up.
As it sets, a solid matrix is created, offering a smooth and solid shape.
One of the biggest advantages of using this material is that there’s very little volume loss and thus, casts made with this are true to the proper size of the mold.
Additionally, it forms a thick surface that can resist normal knocks after drying and isn’t likely to cause any cracking of surfaces.
Apart from offering a great decorative interior finish, tiles and blocks made with this material come with the specific advantages of high fire resistance and lightness.
Aesthetically, ceiling designs made with POP are quite easy to construct.
It’s just a matter of workmanship and creative designs.
And probably that’s the biggest reason a huge variety of Plaster of Paris ceiling designs can be found almost everywhere these days.
This material is also extensively used for general building operations and creating pre-formed building products such as plasterboard, blocks, tiles etc.
Plaster Of Paris Molds
Plaster of Paris doesn’t usually crack or shrink when dry which makes it an ideal medium for casting molds.
It’s generally used to precast and hold different parts of ornamental plasterwork placed on cornices and ceilings.
These molds are often made with additives that improve dry strength, green strength, castability, and permeability (Source).
For instance, magnesium oxide and talc are sometimes added to reduce setting time and prevent cracking.
The plaster pattern is commonly made of metal and is typically coated with some anti-adhesive compound that prevents it from getting stuck against the mold.
Plaster of Paris molds are inexpensive, reusable, fast to create, more accurate compared to steel molds, and can be changed easily.
Plaster of Paris crafts are something that can be made for profit or for fun.
You can always start with an easy project and see what it takes to make awesome artwork.
As this material dries quickly, you can get on with finishing a project quickly.
In addition, you can purchase it at almost any hardware store, where the price would be much cheaper than purchasing it at a craft store.
Even if you are a busy parent and want to keep your kid engaged in a creative manner, POP is a great raw material that can be used by the little ones to create beautiful artifacts.
Here’re some great craft ideas that your kids would really enjoy.
You can conveniently use POP for patching walls by following some simple steps.
First of all, clean the area that you plan to repair with a damp brush or rag and a mild cleaning solution.
Make sure that the area becomes free of grime, dirt, and loose paint or plaster.
Then mix POP with water to make a smooth paste.
Remember to mix up the amount what you’ll actually need because the material hardens quickly.
Now, lightly moisten the area you plan to plaster with a damp cloth or sponge.
This would help the wet POP to adhere better.
Then fill up the crack or opening with plaster with the help of a putty knife.
Now, smooth it flush with the rest of your wall surface.
Finally, apply a high-quality interior paint to the patched area once it’s completely dry.
Let the paint dry completely and decorate with paint or wallpaper as desired.
You can watch this video to learn about the process in detail.
How To Mix
While mixing the Plaster of Paris isn’t difficult there are some important steps that you should keep in mind.
Supplies you’d be needing include POP powder, water, spoon, mixing containers, measuring cup, petroleum jelly, and plastic mat or newspapers.
First of all, cover the work area with newspaper or the plastic mat.
The ideal ratio of a POP mixture is one part water to two parts of POP powder.
Now, measure out both the POP powder and water and keep them in different containers.
Then start adding the POP powder to the water in the mixing container by sprinkling the water over the powder.
Remember not to add the powder in a single spot, try to cover as much area as possible instead.
Then use a spoon to disperse the powder completely into the water and get rid of any air bubbles.
Continue adding powder and once you find that it’s almost covering the water’s surface, start stirring the mixture.
Keep on stirring until the mixture reaches a smooth and uniform consistency.
Finally, if you wish to make colored Plaster of Paris, just add some acrylic paint or poster paint once the mixture gets a smooth consistency.
This video should help you get a clear understanding of the process.
Plaster of Paris comes with an easy-to-mix formula that mixes with water and dries to a durable, dense, and smooth and bubble-free finish.
Though the material sets in a couple of minutes, it takes around an hour before it’s ready to be removed from a mold while taking 24-48 hours to cure fully.
This quick setting time is one of the biggest reasons for which the material is being heavily used by real estate contractors and builders.
Plaster Of Paris Painting
Once you have created something using Plaster of Paris and are now planning to paint it, there is a certain method you’d need to follow.
First of all, let your POP project cure, harden, and completely dry before you start to paint it.
Don’t attempt to paint wet as that might result in a ruined project.
Now, prime the POP by applying acrylic gesso with the help of a paintbrush.
It’d seal the plaster preventing it from absorbing moisture.
Now, allow the gesso to completely dry and start applying the paint.
You can use acrylic paint as it dries quickly, making it an ideal paint for Plaster of Paris.
To apply the paint, you can use cotton swabs, sponges, paintbrushes, and even toothpicks.
It’s important to lay down a disposable tablecloth or a sheet of painter’s plastic before you begin the painting work.
It’d help you avoid getting all over the table or floor.
And remember to keep the curing plaster beyond the reach of children as it becomes very hot during the process.
How To Make Plaster Of Paris Stronger
It’s a fact that Plaster of Paris is brittle and unlike a plastic, for example, it’ll break.
It’s the key reason for which many people have had difficulties while making POP castings.
However, these days, there are some manufacturers that use a solution which could harden the plaster from the outside first and faster.
This prevents the moisture from leaving and creates a harder and stronger overall plaster.
As a result, the final product becomes better and comparatively stronger than the ones made using the traditional Plaster of Paris.
You can get the solution either separately or as part of the POP mixture.