Polyurethane Mold Making Rubber for Concrete & Stamping

Polyurethane Molds for Concrete & Stamping FAQs:

How to Use Concrete Molding and Stamping Rubber 75A Urethane

Concrete molds can be used for creating interesting or technical shapes out of pourable concrete. The polyurethane concrete molds are best suited for portions of concrete, and should definitely be included among your stamped concrete supplies.

Note that if you need finer detail, consider our Mold Making Latex or our AM 128 Brushable RTV Silicone. 

Polyurethane molds for concrete can be used for pourable concrete as well as hard rubber stamp molds. When mixing this product, use only clean plastic containers and stir sticks — paper, cardboard, wax and/or wood will contaminate your mold.

1. Shake both container A and container B vigorously about 30 seconds before pouring
2. Mix the two solutions in a clean plastic container (in a 1:1 ratio) for 60 seconds
3. Pour freshly-mixed urethane molding rubber into a second clean plastic mixing container and mix for an additional 60 seconds
4. Pour into your mold within 5 minutes of this subsequent mixing
5. Let each layer cure before applying a new layer

Pro Tip: Use AeroMarine Products’ concrete molding and stamping urethane rubber between 65° and 75°F in a humidity-controlled environment.

We’re proud to offer industrial-grade materials that provide durability and strength. Like our RTV mold-making kits and silicone potting compounds, this urethane rubber can provide the tear resistance your project requires.

How can I ensure that the concrete does not stick to my molds?

You can use the mold release spray that we sell with the concrete molding and stamping rubber. Please clean your molds thoroughly and dry them completely before your next use.

How easy is it to make my own concrete mold?

Our concrete molding rubber comes in two bottles: Part A and Part B. Mix the two parts at a 1:1 ratio in a clean plastic container.

Once you’ve opened and poured the polyurethane, be sure that you close the lid tightly to avoid moisture contamination or the polyurethane drying out.