5L, 20L & 210L
Place concrete in formwork (3 parts cement, 4 parts sand, 6 parts aggregate by volume in a typical mix) and wood float surface covering all stones. Brush, spray or roller on Cemix® R20 Retarder liberally, to the fresh concrete surface just as the surface water disappears, Protect the coated surface from wind, rain or hot sun. Within 12 – 24 hours after application remove retarded top layer of mortar with a stiff broom and hosed water, leaving a clean exposed aggregate surface. If extremely small is used, it is important not to start the wash off too early as bare spots may be created.
Appearance – Green liquid
Yield / Coverage – Approximately 5m2 per L.
Specific Gravity – 0.98
The data shown above reflects typical results based on laboratory testing under controlled conditions. Reasonable variations may occur on site.
It is important to agitate this product well before use.
Cemix® R20 Retarder has a shelf life of 12 months minimum when unopened in original containers.
Clean all tools with water & brush immediately after use.
The setting time will be influenced by air temperature, cement type, content and slump. If the surface is not washed off within 12-24 hours the surface concrete will set and reach full strength. A trial run is recommended before general application to determine timing and the depth of etch required.