DIY White Cement Screed Mix

The easiest way to get into cement is by casting into pre-made molds.

- cement will take the shape of whatever it's poured into and can have a surprising amount of detail.
- a fun way to see what we're working with is with silicone ice molds, just make sure that you don't use them for anything edible after you've used them for cement.
- since cement has aggregate, we'll have to take that into account before starting a mix.
- even pea gravel aggregate can be much too large for small molds, so consider what you are casting into to determine if you need or want to remove aggregate.

Before pouring your cement mix into the molds, it's a good idea to use a release agent, this will make removing the cement from the mold after it has cured very easy.

The Pacifica mold release agent Works perfectly to line your mold. Spray the release agent into the mold, ensuring coverage in all nooks of the mold. Be careful not to spray so much that the release agent pools and causes drip. If you use linseed oil, apply a thin coat and be careful not to make pools of oil in the mold.

Mix the cement until a good water-to-cement ratio is achieved, then scoop a small amount of the cement mix into the molds. Using a thin stick or skewer to poke the cement into all areas of the mold.

Smooth and level the mold with the trowel, remove any excess cement and clean up the edges so there's less over-pour flashing that needs to be cleaned up later when the cement is cured. Then, vibrate your mold to release any air bubbles and allow the mix to settle in the voids of the mold. Using different techniques, vibrate the mold to release any air bubbles.

Shake the mold, tap it, vibrate the table by striking a hammer around the mold, or use a power tool like a sander to cause the mold to vibrate and release any trapped bubbles. Since these molds are silicone, you can also stretch and warp them to help get air bubbles out in addition to the vibrating methods.

Any over-pour of cement will set around the backside of the casting, this excess pouring is called flashing and can easily be removed. Since flashing is so thin it can be broken off with your fingers, and the edges can be smoothed over with 120 grit sandpaper.
Making solid cement casts is easy, just remember the basics: Achieve a good mix, use mold release, and vibrate our air bubbles.

Use the Pacifica cement oxide dyes if you want to add some colour to your creations!

Cement typically takes 24 to 48 hours to dry enough for you to walk on it. However, cement drying is a continuous and fluid event and usually reaches its full effective strength after about 28 days.

It might take a little longer in the winter to cure because of the colder temperatures.