Rear Window Installation

Finally it was warm enough (sounds like we were due, huh? No, we're really lucky this year to get a warm spring-like weather just around New Year's - it was at 78F today!! God, I can so see the envy in your face :-) ).
I didn't feel like finding excuses to not work on the plane any longer and so I just removed the tarp from the fuselage and started fitting the rear window. Remember, I ordered the plexiglass version of the rear window which is provided by Carl Eldridge and is fuel resistant and mine is also tinted to reduce the heat in the cockpit and of the fuel a bit. The Lexan version Van's provides is pre-drilled so you can cleco the window to the rear and side skins before match-drilling the front to the rollbar. Well, it's not that easy with the plexiglass version. First it is not pre-drilled so you will have to align it by yourself as well as stabilize it during the first holes drilled.
Furthermore, there is a section in the center rear that interfere with some brackets on the inside of the cockpit and the window has to get trimmed to clear these brackets. Not too much though to leave enough beef for the screws to hold the window onto the sheet metal.


This shows the right side bracket in question. See the little cut out that allows the window to pass the bracket. That has to be trimmed off. I used the Dremel cutoff wheel and the sander piece to trim this.
The way I marked the area was by sliding the window in place and pushing as much aft as possible until it hit the brackets. Then I aligned the sides to so they were even and then I marked the bracket area which is right around the outer forward screw holes.


The blue marks show what to remove. I repeated this step around 4 times until I had a good and tight fit.

The next challenge was to support the window against the gravitational droop to accomplish a better fit during drilling.
I used a piece of 2x4 to do that.



With these problems all out of the way I started drilling on the rear holes as the front stays well in place just by its own weight. The aft section not so much as it held to the sheet metal by the eventual screws only. Also I used an older #40 drill bit that I drilled into concrete to dull it up enough to not crack the plexiglass.



This is as far as I went on the rear side before I switched over to the rollbar match-drilling. I felt I needed some better support for the front before finishing the sides as I think this will result in a better fit that way.



I couldn't finish the job as I ran out of clecos. Partly because I needed the #40s in the rear to hold the window to the sheet metal (the Lexan takes #30s there as it is pre-drilled) and partly because the plexi is a bit stiffer than the Lexan and likes more screws holding (and forming) it to the rollbar. I'll order some more and then finish the task. It looks really nice so far.