Directions for applying Mr Crystal
Description
A cement based waterproofing compound that chemically reacts with moist cement based substrates forming insoluble crystals in the capillary tracts of the substrate waterproofing the concrete yet still allowing the surface to breathe.
Coverage
1 Kilogram will treat 4.5 metres of crack.
Surface Preparation
Apply to cement based surfaces that are free from dirt, dust, grease, oil, efflorescence and other contaminants. With tanks and troughs you can use a scraper and wire brush. Using an angle grinder will give fast accurate results. With a grinder, remember, you are not trying to cut concrete, just "bullying" the contaminants off the surface. Structure to be repaired must have basic structural integrity. Clean out and patch cracks larger than 0.25mm thick with a sand and cement render. Use caustic soda solution to clean oil contaminated surfaces then thoroughly hose down to completely remove contamination. Wet down thoroughly the surface to be coated immediately prior to application.
The above photo shows a trough being cleaned down thoroughly in readiness for a Mr Crystal application.
Temperature
For best results, apply Mr Crystal when outside temperature is between 10C - 25C.
Mixing
Mix only the amount that can be used in 10 -15 minutes. Mix .5–1kg with water and bring to a thick paste. Mix thoroughly and add water or product to bring the mixture to a thick creamy, yet just paintable consistency. The final ratio should be about 1kg powder to 375 mls. water.
Application
Mr Crystal can only be applied to wetted cement-based substrates (splash some water on the crack as you go). Apply a strip of mixture 60mm wide with the enclosed brush directly over the crack, working the mixture well into voids. To prevent segregation and keep a uniform mixture stir the mixture frequently during the application and dip brush deep into the mixture so that a thick coat can be applied. You may notice that the first coat appears patchy. As this first coat begins to go tacky, apply a second coat. The "tacky" first coat will "grab" the second coat enabling you to build the mixture up to a total of 6mm thick.
Where to apply Mr Crystal
Mr Crystal can be applied over or adjacent to cracks, suspected weak points, cold joints, porous surfaces, around fittings. Mr Crystal can be applied to either side of the face of the concrete. Mr Crystal migrates through the voids in the concrete and has been known to migrate up to 400mm from the point of application. The resultant crystal growth is the waterproofing effect of this product. The raw product itself is not waterproof (in fact, it is highly absorptive by design).
When applying Mr Crystal where there is flowing water, remember not to be too concerned that some product may wash off. It is important to focus on the intact material (that hasn't washed off) to ensure that it is correctly applied, cured and stimulated.
Tip: If the water is running down a vertical crack and washing the material off try this. Take some short drinking straws, squeeze one end into the crack and leave at a sharp downward angle. This will take a good bit of the water away from the wall. A piece of tie wire with one end flattened will also be effective. Even a shovel or hammer handle leaned against the leak will divert some of the water away from the area to be treated (much like how water runs off the end of your finger in the shower) They can be removed as product hardens.
Curing
Protect the surface from rain or frost during initial cure. (Aprox 2-3 hours). Water cure the treated surface by mist spraying with water 3-4 times daily for 3 days if you wish to hasten the crystal growth. This is helpful on structures that are not intended to hold water. (Eg. Concrete silo bases) In the case of tanks, troughs etc. simply putting some water back in will provide adequate hydration. Even 20 litres of water added to an empty tank with lid replaced will provide a good humid environment to hasten crystal growth.
Tip: On a sunny or hot outside wall, draping a wet bag over your work will help.
