1. SURFACE PREPARATION: Remove loose or flaking concrete with a wire brush or sandblast the surface to insure proper bond of the crack paste (#1002 FS, #1004 FS, #1305 FS, #1183). Use the POLYBAC#20 Solvent to remove dirt, grease, paint and remaining contaminants that may affect the adhesion of the epoxy. Always wipe the surface prior to applying the epoxy no matter what method of removal is used, ie. power washing, sandblasting, wire brushing, scraping, etc.

2. INSTALLING INJECTION PORTS: Surface mounted ports are most commonly used for injection into concrete. Mix a small amount of the crack paste and apply to flange portion of the port careful not to cover hole. A small amount is needed to "tack" the port in place. Place port directly over crack and press firmly to insure good bond. The ports are placed 8-10 inches apart on 10 inch width concrete. Drill ports can be used for wider cracks or in corners where surface mounted ports cannot be utilized. Closer intervals are required when using drill ports or injecting hairline cracks. Surface mounted ports eliminate the chore of drilling into the concrete thus reducing labor, time, and clean-up.

3. SEALING THE SURFACE: The #1004 FS (no-odor) and #1002 FS (odor) are the recommended crack pastes used to seal over the surface mounted ports and exposed cracks. The paste is formulated to cure within 20 minutes at 75° F. The more paste that is mixed at one time, the faster it will cure. Mix in small amounts to avoid waste.

   The fast setting crack pastes give an excellent surface seal with high bond characteristics which allows injection under extreme pressures. The entire exposed crack should be covered with the paste leaving only the port holes uncovered. The paste should extend 1-2 inches on either side of the crack and feather-edged to reduce seepage.

   The crack paste is cured and ready for injection when you cannot make an impression in it with your fingernail. It the concrete is cool, mix a larger portion of the crack paste and apply it in thicker layers to cure faster.

   Structural cracks move when concrete goes through a temperature cycle, which occurs normally over a 24 hour period. Surface seals will frequently crack from movement if not restrained by epoxy injection. This condition requires the scheduling of injection within 6 hours after sealing the crack.

4. INJECTION: Using either the POLYJECTION machine or the POLYJECT #1001 injection cartridge, inject into the lowest port on the wall until the epoxy begins to flow from the port above it. Plug the first port with the cap provided and move up to the next port, repeating the procedures until the entire crack has been filled with the epoxy.

   Wide cracks will accept epoxy freely and do not require high pressure. Tight cracks, however, may require intermittent injection at higher pressures. Slow, constant pressure is recommended to reduce the possibility of leaks or blow-outs. If you feel pressure building within the cartridge, allow a few minutes for the material to seep into the crack before applying additional pressure. Remember, liquids cannot be compressed and need time to penetrate the crack.

   Hairline cracks will require special care. The injection epoxy will perform best at temperatures above 75° F. Hairline cracks will accept a smaller volume of epoxy in a given period of time but will penetrate a large area of cracked surface. Patience is required to effectively seal a hairline crack.

5. FINISHING THE REPAIRED STRUCTURE: After 24 hours at room temperature, the injection ports can be removed. This allows adequate time for the epoxy to cure and penetrate into the cracks. The ports can be removed by striking with a trowel or hammer. If cosmetic appearance is preferred, the surface seal can be chipped, ground (with sanding disc), or burned off. The epoxy is paintable if grinding is not desired. Wear protective clothing and breathing apparatus while grinding or burning.
   Caution: Burning of crack paste may produce toxic fumes.

This is a general guide to injecting POLYGEM’s epoxy in clean, dry cracks. Please contact POLYGEM's technical service department for additional information on injecting in other specific applications such as: Actively leaking cracks, moisture or oil saturated cracks, cracks with voids and slab delaminations.