Q: What is Rapid Set® Mortar Mix?
A: Rapid Set® Mortar Mix is a blend of high-performance Rapid Set® Cement with washed plaster sand. It provides rapid strength gain, high durability and low shrinkage. Use for horizontal, vertical, and overhead plaster and concrete projects. Simply mix with water and it will reach structural strength in one hour.
Q: Is this a modified portland cement product?
A: No. The high-performance properties come from the Rapid Set Cement in the mix.
Q: How soon can I color coat?
A: Apply color after the product is hardened and dry which usually takes 1 to 4 hours.
Q: How soon can Rapid Set be painted/coated/sealed?
A: Rapid Set reduces the waiting time prior to coating. Under dry conditions, water based coatings such as latex paint can be applied after the products is hardened and dry which usually takes 1 to 4 hours. Solvent based and Impermeable coatings such as oil based paint and epoxy can be applied in 16 hours. Experience has shown that some coatings can be applied in much less time. Follow the coating manufacturer’s recommendations for surface condition.
Q: Is a bonding agent necessary?
A: Bonding agents are not required. Proper surface preparation is the main component in achieving a good bond. If bonding agents are desired, they should be used as a supplement to good surface preparation, not as a substitute.
Q: Can I blend other products with Rapid Set Mortar Mix?
A: Blending with other products may give unpredictable results and is not recommended. The use of Rapid Set approved additives and various colors are acceptable.
Q: How thick can I apply this product?
A: From ½ inch to 6 inches.
Q: Is Rapid Set Mortar Mix air entrained?
A: Rapid Set Mortar Mix is air entrained except for the product made in California.
Q: How do I mix it?
A: Just add water. The use of a mechanical mixer such as a mortar mixer or drill mounted mixer is recommended. To maximize working time, organize work so that all people and equipment are in place before mixing.
Q: How do I place and finish it?
A: Using traditional methods, place and strike-off to desired level. Rapid Set is fast and does not bleed water so apply your final finish immediately after placing. Organize your tools and people so you can work quickly. On flat work, fill to full depth and proceed horizontally. Do NOT place in layers.
Q: How do I cure Rapid Set Mortar Mix?
A: Water cure all Rapid Set Mortar Mix installations. The objective of water curing is to maintain a wet surface until the product has achieved sufficient strength. Begin curing as soon as the surface has lost its moist sheen and continue for a minimum of 1 hour.
Q: What are common applications for Rapid Set Mortar Mix?
A: Rapid Set Mortar Mix is an all-purpose repair product. The most common applications are vertical and overhead applications, and general concrete repair.
Q: How do I increase the working time?
A: You can increase the working time by lowering the mix temperature or using set retarding additives. Lower the mix temperature by keeping product cool and using chilled mix water. Rapid Set® SET Control® additive will increase working time and is available through our Concrete Pharmacy®.
Q: Can I use color?
A: Yes. The color of Rapid Set Mortar Mix can be modified by using dry powder pigments designed for use in cement mixes.
Q: How do I prepare the surface?
A: Roughen the surface and remove all damaged or contaminated concrete. Make sure the repair surface is not contaminated by oil, paint, acids, dirt or other materials that will prevent a good bond. Immediately prior to placement, saturate the repair surface with water then remove any standing water.
Q: How much do I need?
A: One bag of Rapid Set Mortar Mix yields approximately 0.5 cubic feet. That is one square foot, six inches deep. For plastering, it will cover 8 square feet at ¾-inch thick. If you need an answer more specific to your application, use our Concrete Calculator.
Q: Can I use it in wet applications?
A: Yes. Rapid Set Mortar Mix is made with Rapid Set® Cement, which is a hydraulic cement. A hydraulic cement hardens under water.
Q: What is the shelf life?
A: When stored in a dry location, in an undamaged package Rapid Set Mortar Mix has a shelf life of 12 months.
Q: Does temperature affect Rapid Set Mortar Mix?
A: Cold temperatures will slow the setting time of Rapid Set Mortar Mix and warm temperatures will speed it up. Greater changes in temperature will have a more pronounced affect.