JAHN M125

Thin-set Mortar

This single-component, cementitious, mineral based mortar is designed for the restoration of many masonry surfaces. It's ideal for repairing thin spalls and filling cracks or voids. Jahn M125 is completely vapor permeable and contains no latex or acrylic bonding agents or additives. M125 is formulated for compatibility of many masonry substrates and is available in Custom Colors.

Features And Benefits

*Single-Component: Mixes with water only, improving quality control and consistency of application.
*Contains No Latex or Acrylic Bonding Agents: It protects the substrate by allowing salts, water vapor, and liquid water to reach the surface, preventing failure due to salt expansion or freeze/thaw cycles.
*Tenacious Adhesion: Strong bonding capabilities without relying on synthetic bonding agents.
*Factory Controlled: No field chemistry resulting in product variation.
*Custom Colored Upon Request: Closely matches existing masonry. Choose from Standard or Custom Colors.

Application Procedures

Surface Preparation
Surfaces to receive M125 must be sound and free of all dust, dirt, grease, laitance and/or any other coating or foreign substance which may prevent proper adhesion. Remove all loose and deteriorated masonry from the repair area using manual or pneumatic cutting tools. Do not install M125 on unsound masonry.

Mixing
The mixing ratio is approximately 3 1/2 to 4 1/2 parts powder to 1 part water by volume (or until material is easy to spread), depending on temperature and humidity. More water may be required as ambient temperature rises. The mixing may be done by hand or by mixer, stirring until the mortar is thoroughly mixed. The mortar should be the consistency of putty. M125 may also be mixed using a slow speed drill (400 - 600 rpm) equipped with a Jiffler-type mixing paddle. For best results, add the powder to the water slowly. The working time will vary, depending upon wind, temperature, and humidity. Using excessive water in the mixture may affect the color of the repair.

Application
Moisten the substrate using clean water. Jahn Mortar should be applied to a well-dampened surface (with no standing water). If the surface is allowed to dry out before applying M125, this step must be repeated. This is very important.

For a smooth finish, build up material flush to surface. The waiting period before finishing will vary, depending upon wind, temperature, and humidity. After initial set, trowel the M125 to achieve the desired finish. For a rough textured finish, build up material beyond the surface of the original stone. After achieving initial set, scrape away excess mortar until the desired profile is reached.

Curing
Periodically mist M125 repairs using clean water for at least a 72-hour period. The timing for initial misting will vary with ambient conditions. Hot, dry conditions may require misting in 30 to 60 minutes. Cooler, damp conditions may require waiting several hours before beginning the curing process. Mist several times a day. Should access to the repairs be impossible over a period of time, plastic may be used to cover them temporarily. The application of plastic, however, does not remove the need for normal curing techniques.

Clean Up
Remove uncured 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 around the patch (staining of adjacent masonry). Cured mortar may only be removed chemically or mechanically.

Safety Requirements
It is recommended that safety goggles, gloves, and a dust mask equipped with P-2 filters (or equivalent) be worn for protection while mixing.

Limitations.
* Do not apply Jahn Mortar to a frozen or exceedingly hot substrate. The applied mortar must be protected from extreme heat, freezing, excessive wind, direct sunlight, and rain. Ambient temperature range should be 40° F to 90° F with low to average humidity.
* Do not add bonding agents to Jahn Mortar or use them as surface preparation materials.

Packaging and Coverage
M125 is available in 2 and 5-gallon pails. This will cover 0.2 cubic feet and 0.5 cubic feet respectively.

Storage And Shelf Life
Store material in a dry area away from direct sunlight. Ambient storage conditions should be in the range of 40° F to 90° F with low to average humidity. Average shelf life is 6 months in original, unopened packaging.

Technical Data
Jahn M125 - Thin-set Mortar

Warning
Not for internal consumption. Keep out of reach of children and animals.

Product data last updated 8/2002