Many of the recipes, props, and tutorials that are shared to create creepy looking Halloween props are created using monster mud. Monster mud is a blend that is applied like paint to props in order to create a hard shell exterior to make them hold up outdoors. Here’s how to make your own…
MYO Monster Mud
What is Monster Mud used for? Well, to create fantastic props, like the Eternal Wait shown above. Cotton Mop strings can be dipped in the monster mud and draped over a plastic skeleton or skeletal prop to create the effect.
You’ll Need:
Drywall Joint Compound
Exterior Latex Paint, stirred well
Drill Mixer Bit
Bucket
Attach the drill mixer bit to the drill and open the joint compound. This is a prepared compound, not the dry kind that you add water to. The mixture needed is 5 parts Joint Compound to 1 part Latex paint. How much you mix is completely up to you for the project you need.
For example, if you need 6 cups of mix, you’d use 5 cups of joint compound and 1 cup of latex exterior paint. If you need about a gallon worth you’d use approximately 12 3/4 cups joint compound and 3 1/4 c. paint.
It doesn’t matter what color you use, but it is recommended to use dark grey or green, etc to make it blend in easier for your prop. Combine the ingredients in a bucket, Mix with the drill bit until it’s very smooth.
How to Use it
Apply the monster mud over burlap, paper mache, etc painting it on. It will take about 24 hours per coating to dry, so keep that in mind. Do not apply it too thickly or it will crack. Repeat layers as needed.
How to Make Monster Mud – Watch the Video:
How to Seal Monster Mud aka Monster Mud Waterproofing
Once the creature dries completely, you might find yourself worrying about how you’re going to preserve it. Luckily, if you’ve used exterior latex paint, as recommended, the monster mud has a natural seal built in. While this is generally moisture safe, you’ll want to ensure the monster isn’t left in the pouring rain.
If you’d like to display the monster mud creations on a covered porch or patio, they should be just fine. We leave ours out for about 8 weeks every year with no ill affects.
If you’ve used indoor latex paint, you’ll want to apply a waterbased polyurethane. If you’d like you can apply this using a spray bottle in a well ventilated area.
Another option is Dry-Lok, which comes in two colors, white or gray. Keep in mind that this will affect the final coloring of your monster mud creation.
Image Credit: The Eternal Wait by Mike_Pants
The 5:1 ratio of joint compound to latex paint is pretty thick and perfect for a variety of applications, like troweling it onto fake gravestones, or hand application to wall panels to create a faux-stone texture.
By mixing the ratio 2:1 the monster mud can be applied by brush, or shot through an air-powered texture sprayer.
If you need a variation, you can use powdered thin set joint compound. Thin-set can be sold as floor tile mortar or ceramic tile mortar. This is a more budget friendly option, as it’s considerably cheaper.
A couple of benefits to using the thin-set is that it offers a better bond, increased strength (so it’s great for props that will be outdoors for long periods of time), less shrinking as it dries – which means fewer cracks, and it doesn’t degrade in water. The gritty texture feels a lot like stone.
The mix ratio should be 1:1 for a thick version and 1:2 for thin-set brush on or spray on applications. When using the thin-set mortar, I like to seal my creations with Thompsons water seal.
Thank you, we soaked a few pieces of cheesecloth into the mixture, then draped it to create a ghoulish outline, I wanted to add a bit more texture to it. The air-powered texture spray idea is brilliant.
For those of you wondering about the durability of Monster mud, it’s is strong but brittle. The main ingredient in most brands of joint compounds is gypsum or chalk. If you want added strength, use the thinset mortar instead of joint compound.
Although adding latex paint to it makes it more flexible, it does very little to make it weather resistant. You definitely want to use the Dry-lok that’s recommended in the post.
How Strong is Monster Mud
While Monster mud is quite strong, it has a tendency to be brittle as a result of the chalk or gypsum based texture compound. By combining a quality joint compound with a decent exterior paint, the creation will dry to a stiff faux-stone like consistency.