Sash and Sash Preparation
- Rabbet depth and rabbet width of sash openings are to be in agreement with Plexiglas® glazing design Tables 14(A, B, C, or D) or Table 15. Rabbet should engage the Plexiglas® glazing on all edges.
- Remove all projections, such as burrs in the sash rabbet.
- All surfaces of wood and steel are to be prime-painted by others before application of glazing compound or sealant. Aluminum sash is to be cleaned with recommended solvents to remove protective finishes and grease.
- Apply sealant manufacturer's recommended primer to the sash to ensure proper adhesion by the sealant.
Plexiglas® Sheet Glazing Preparation
- Accurately measure the inside width and height of each sash opening before cutting Plexiglas® sheet to size.
- The height and width of the Plexiglas® acrylic sheet are to be cut shorter than the overall inside sash opening dimensions to allow for thermal expansion by the amount shown in Tables 14(A, B, C, or D) for intermediate and large light glazing.
- After cutting the Plexiglas® sheet, the cut edges should either be scraped or sanded to provide edges smooth and free of chips or hairline cracks. This step ensures optimum impact strength.
- Unmask Plexiglas® acrylic sheet just prior to installation.
- Protect Plexiglas® acrylic from excess sealant smears with a paperback adhesive tape around the edges adjacent to the rabbets.
- The edges of Plexiglas® acrylic sheet are to be thoroughly cleaned with VM&P naphtha before setting in sash.
Specify sealants and glazing details. Suggested glazing details are shown on the following page for small, intermediate and large glazing. Sealants should be applied in accordance with the manufacturer's recommendations. The use of 1/8" thick neoprene setting blocks and acrylic terpolymer heel beads is optional.
Some gasket and sealant materials while in contact with Plexiglas® sheet could cause crazing of the sheet under certain conditions. Before using any such materials, the contractor should test them thoroughly, duplicating end-use conditions as closely as possible, to ensure their compatibility.
Cleaning and Finishing
- Glazing compound and masking paper adhesives are to be removed from Plexiglas® acrylic sheet by using a soft cloth wetted with VM&P naphtha or kerosene, followed immediately by a thorough cleaning with soap and water.
- Do not use razor blades or other sharp instruments, such as a putty knife, to remove spots.
- Clean Plexiglas® acrylic with a soft damp cloth or chamois, wiping the surface gently.
- Wash with mild soap or detergent and water, or household ammonia and water. Use as much water as possible in washing. Apply to large areas with a bristle mop used in window washing and to smaller areas with a clean soft cloth, sponge or chamois.
- If it is necessary to dry the washed surface, use a clean damp chamois.