Set times of all Jesmonite composite materials can be extended by the addition of Retarder to increase working time. This Retarder is for AC100, AC200 and AC300, and a separate Retarder for the cement based materials AC730, AC830 and AC930.
Please note that you should perform tests in the workshop environment, as extremes of temperature and humidity can effect set times. Addition rates can be found in the individual composite user guides.
Jesmonite Retarder can be added to the pre-weighed liquids to extend the pot-life of the mixed material.
Typical inclusion rates are between 2g–8g, however a small test is recommended, as the precise timing is dependent on both temperature and mix size. 2% addition will make the set time approximately 25-30 minutes.