IMPORTANT: Retarders are not interchangeable for AC100/200/300 vs AC730, ensure you use the correct retarder.
The working time (also called pot-life) of mixed Jesmonite is approximately 8-15 minutes depending on your environment and mix size.
The addition of the appropriate retarder can extend this closer to 30 minutes at a maximum inclusion rate of approximately 2%.
The typical inclusion rate of AC100/200/300 Retarder and AC730 Retarder is approximately 2g-8g per kg of mix. Please perform tests in the workshop environment as varying temperature, humidity, and mix sizes can affect set times and pot life and the necessary addition rate will vary.
The Jesmonite mix starts to harden way too quickly to be able to get creative with colour mixes etc. when pouring multiple items. The retarder is absolutely essential!
I was skeptical about how this would affect the mix and setting time, but it really works! It's been so humid here and I've been struggling with the jesmonite curing almost immediately. This has extended my working time so I can make multiple pieces with one batch of mix. Highly recommend!
With the right amount, the retarder did extend the potlife of my mix. I was able to gain a few more minutes to be able to switch colors.
The retarder really helps extend your working time. Ensures I have enough time to pivot or adjust, like when I decide to change up the colors 👍🏽