The sliding windows have always been hard to open and close. Pretty quickly I could see that the aluminum end pieces on each “Plexiglas) window sash were rubbing on the tracks that the windows slide in. Removal of both end pieces allows easy removal of the actual window pane, by warping it slightly to get it out of the tracks. To remove the aluminum, I used a putty knife between the “glass” and the aluminum to break the bond of the RTV that was used to fasten the end pieces to the “glass”. Then a whack with a small hammer at the bottom to the end of the putty knife freed it from the glass. While the aluminum was off, I shortened each piece by less than 1/8″. While the two panes were out of each window I cleaned the tracks with a toothbrush and Simple Green. In the shop, cleaned out the slots in the end pieces with a putty knife and 5/32″ welding filler rod to remove all the old RTV. Also, shortened the plastic panes’ (height) by a table saw blade’s thickness to make them easier to slide in the track. Sanded the edge to remove any burrs.

Reassembly:

Inserted the outermost pane into its track Then added the end pieces after adding new RTV to the groove in each piece. On several windows, the outer pane, when opened, pushed the fuzzy furring/weather strip out of its track. Was able to push it back into place then crimped the ends of all tracks with pliers.

Knobs: I thought that adding small knobs to each window ‘sash would make them easier to operate. (There are already holes drilled in the “latch”side of each sash.) I looked high and low for a knob small enough to fit the location. Maybe 3/4″ diameter by 1” tall. I have yet to find anything that will work.