ADITIVES

Retarder

Set times of all Jesmonite Composite materials can be extended by the addition of Retarder to increase working time. There is a Retarder for AC100/200/300, and a separate Retarder for the cement based material AC730. Please note that the end user should perform tests in the workshop environment, as extremes of temperature and humidity can effect set times. A guide to addition rates is covered in the Instruction sheets available to download in 'the knowledge' section of this website.

Thixotrope

Thixotrope is added so that the viscosity of Jesmonite can be adjusted to the users preference. This is particularly useful when applying a Gel Coat into a mould. By adding Thixotrope it is possible to apply a controlled 1mm ? 3mm layer of material without it running off the mould surface. This also prevents glass reinforcements from showing at the face of laminated objects. Thixotrope can also be used to make the material into a paste, which can be used as a repair filler, and jointing paste for bonding two laminates together.

Acid Etch

Acid Etch is used to expose the fine decorative aggregate in Jesmonite AC730 materials. The acid removes the cement rich film from the surface of objects moulded in AC730 to produce a stone finish. When diluted with water it can also be used as a cleaner for removing marks from AC730. Please refer to the AC730 users guide for further technical information.