in place, I cut struts to fit between the frame and lifeline brace. The struts are cut 1/4- to 1/2- inch longer than the distance between the frame and bent brace. I also had a pocketful of wood shims to fine-tune the pressure on the frame and window. The brace flexes as pressure is applied and the struts interact. With the window in the opening and fixtured from the outside, I carefully cut the protective paper with a razor knife, following the inside opening. It is impossible to cut the paper without scribing the acrylic as well. Do not worry: the scratch does not show after the installation is complete.
Certain urgency We double-checked the fit and confirmed that all the tools, braces, shims, and rags were ready. The process took on a certain urgency once the adhesive started to flow down the mixing tube. It was time to commit. Plexus MA320 is a two-part meth­acrylate adhesive mixed 10 to 1 by volume. This ratio is metered in a special dispensing tube with a caulking-gun­like dispenser. The components are combined in a static mixer attached to the end of the dispenser. The working open time is 8 to 12 minutes depending upon the temperature. I set a timer, and my wife, Sandy, monitored the countdown as		I started applying the adhesive to the window flange.It was difficult to squeeze the dispenser gun while tracking an even bead, so I made sure I had a goodly amount applied to the flange and tooled the adhesive smooth with my finger before inserting the window. (Wear gloves, don't get this stuff on your skin. -Ed) A putty knife might work as well. To assure a minimal adhesive thickness, we scattered 0.030-inch glass beads on the wet adhesive. Sandy and I placed the window in the opening and erected the fixture. We inspected the gap between the acrylic and cabin trunk and added more adhesive if it was not filled. Then we tooled		the joint off with a finger and removed any excess globs with a scraper. Fixture time is 30 minutes. A cautionary note: mask the area around the window opening well; once the MA320 cures, it owns whatever it touches. Forms a bead Some adhesive extrudes to the inside of the window and forms a bead. It is easier and much cleaner to deal with the excess after the MA320 has cured. I scored the bead by tracing the inside of the opening again with a razor knife. The protective paper acts as a release layer and carries the excess adhesive when peeled away.
				I was dissatisfied with the distribution of adhesive on part of one flange; I either had insufficient clamping or too little adhesive. Structurally it was sound, but an irregular line was visible from the outside. It was clear that the flange was not completely wetted. I masked the inside of the window and window frame with low-adhesion masking tape and forced more adhesive into the joint with a 2- inch putty knife.. The gap filled smoothly. With that long day of work completed, Sandy and I can now enjoy a fresh, clear view out the cabin windows. Sandy meticulously waxes, polishes, and varnishes, but replacing the windows added a sparkle we had not seen in years. Twenty years from now we will be ready to do it again.

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