INSTRUCTIONS: JAHN MORTARS
Mixing: See Mixing Chart for mixing ratio of dry mortar to water. Depending on temperature and humidity, more water may be required as ambient temperature rises. See data sheets for specific instructions and substrate preparation. Do not install feather-edged repairs with Jahn Mortar. Using excessive water in the mixture may affect the color.
Application: Repair Mortars: See data sheet for specific instructions on all individual mortars. Remove all unsound material from substrate before patching. General Instructions for Patching: moisten the substrate using clean water. Jahn Repair Mortar should be applied to a glistening wet surface. If the surface is allowed to dry before applying mortar, this step must be repeated. The next step of the application is what CSP has termed the "Peanut Butter" coat - an 1/8 inch thick layer mixed to the consistency of wet putty. Apply the "Peanut Butter" coat to the glistening wet vertical substrate, then trowel the drier Jahn Mortar (see chart for mixing ration) into the "Peanut Butter" coat. IMPORTANT: to achieve proper bond, the "Peanut Butter" coat must not dry out prior to the application of Jahn Mortar mix! Build the material out beyond the surface of the original masonry. After achieving initial set, scrape away excess mortar until the desired profile is reached. Due to the effects of heat, humidity, and wind, the waiting period for scraping should be determined on the job. In hot weather the mortar may require scraping within a short time, while in cold weather the wait time may be several hours. Repairs should not be floated or heavily troweled to achieve the finish, since this can alter the texture, porosity, and color of the material.
Curing: Periodically mist repairs using clean water for at least 72 hours. The timing for initial water misting will vary with ambient conditions. Hot, dry conditions may require misting within 30 to 60 minutes. Cooler, damp conditions may require waiting several hours before beginning the curing process. Mist several times a day in hot weather.
Clean Up: Remove mortar from the perimeter of the repair before it dries using clean water and a rubber sponge. Repeat several times with clean water to prevent a halo effect on the adjacent masonry.