How to make precast concrete molds

There are many projects that can be facilitated using precast concrete molds. Use them to create steps or balustrades for a building. Create accent pieces like birdbaths or sculptures and anything else you can think of. Using molds made from materials poured right on site makes it easy to create those pieces for immediate use. You can even make multiple castings without delay. Here are the steps to making precast concrete molds.

The first step is to seal any holes in the items you are using as casting molds. You might use caulking or any other sealing agent. Let it dry and add a second application. Let the agent go over the bucket or container you use to form the mold. Latex or rubber is ideal and often used because it is resistant to abrasion and tears.

You will create your mold’s pattern by placing objects in the bucket. Be sure to leave a gap between each object in your mold. Overlapping gaps lead to weakened areas of the mold which could make it tear. After you have arranged your objects you will pour the rubber or latex over the top of them. Let the rubber or latex dry completely.


The ideal solutions for the casting are found at specialty mold rubber manufacturers. A mixable form makes it even easier to cast your mold. Pour enough of this mixture over the objects to cover them, too, but do not cover them completely. Let the rubber or latex dry thoroughly.

This step should take just one day. Once the rubber has dried you can remove your mold right out of the bucket or container. You will know that it is completely dry if it slides right out. There are some molds that require the help of a razor blade or a utility knife to cut the mold free. There will be some overlap on your mold. Trim it away.

The last step to creating the precast mold is spraying it with a concrete releasing agent. Pour the cement over the mold and let it dry. Your objects will be ready for use, and the mold will be ready for another casting right away. These molds last for a long time and handle many castings which allows you to save time, effort and money. You can make any precast concrete mold you choose right on site so be imaginative.

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