5.3.5 Install Windows in Doors

The first step for installing the windows is to cut the opening for those windows. Unlike the rear fuselage windows and the front windshield, the markings the factory makes on the doors is only a “suggestion”. The manual recommends that the builder extend the lines from the rear windows through the door and to the front. That’s easier said than done with a curved fuselage, so I decided just to use some string lines and a lot of measuring. You can see how I did that below. (The original factory markings are below the masking tape. If I had used those markings I would have cut into the strengthening beams the factory installs in the doors.) And just to make sure that what I had marked here works, I placed my 1000 watt work lights on the outside and then looked at my markings from the inside to see if everything lined up ok. In some cases I had to adjust the masking tape slightly to get everything to work.

Fuselage - Door Window Pre-Cut Markings

The door windows are supposed to line up with the rear fuselage windows. Here I'm using string lines to try to get that as close as possible.

Before installing the windows in the frame, I need to grind down the edges so that the business part of the window sits flush (or as flush as possible) with the outside of the door. I got them both close, but not perfect. I’ll have to do some work on the outside of the door to help them appear to look flush. Everything is a tradeoff, it seems, when trying to install these windows!

Fuselage - Door Window Trimmed

Before installing, the window edge needs to be trimmed down so that the main window part sits flush with the outside of the door.

In the photo below, the frame in the door where the window sits gets slathered with Velocipoxy and Micro-balloons. That helps to lock the window into place, but eventually, more Velocipoxy + Micro gets slathered over part of the inside frame of the window as well. All of this is exposed area so in the end, the epoxy-created “frame” needs to look really nice. That turned into a bigger pain than I thought it would.

Fuselage - Door - Window Epoxy Prep

The area that the window sits in has Velocipoxy plus Micro-balloons placed in the edge to glue the window into place.

The windows that get installed in the fuselage are fairly easy to fit. See Section 5.1.0. I can’t use the “popsicle stick” method for holding these windows in place while the epoxy cures, so I came up with the clamping method as shown below. Basically, I bought a bag of L-brackets at Home Depot, bolted them together back to back, then added some rubber bumper thingies similar to those used on cabinet doors to provide pressure. I screwed those to the stiffeners around the doors (the holes later got covered over with finishing epoxy). Other builders use other methods but this seemed to work for me.

Fuselage - Door Window Fitting

Using some homemade clamps to hold the window in place during the trimming process to get it to fit.

In order to get the window to lay flush with the outside, I needed to do a lot of grinding around the perimeter of the plexiglass. (See above.) That means, of course, that the window needs to be trimmed oversize - small enough to fit into the area of the door for the window but large enough to fit into the actual window hole in the door! In the photo above you can see a black Sharpie marking around the perimeter. That’s the part of the window that gets epoxied and matches to the opposite side of the window that actually is visible.

Fuselage - Pilot Door Window

Using clamps and a weight to hold the window in place while the epoxy cures.

The window needs to be firmly locked into place while the epoxy cures. I’m using both the L-bracket clamps and one of my “weights” to hold it down. While I tried to get the original layer of Velocipoxy with Micro Balloons as smooth as possible, it didn’t really happen. Since I needed to fill the holes where the clamps were, I used that excuse to work on sanding out and filling with more epoxy to get this looking as nice as possible. None of this area gets covered so what you end up doing here is for all of the world to see.

There’s a panel that covers up the mechanics for the door latch. The construction manual kinda leaves it up to the builder to decide how best to do that. Well, some builders made foam and fiberglass “mounts”, others used small chunks of wood, etc. I bought this dowel rod from the hardware store. It’s about an inch and a half in diameter. In order to get the cover to sit close to flush with the door frame, each dowel needed to be one inch high. I set up my chop saw for 1” and sliced off a bunch of pieces from the dowel rod. Once that was done, I drilled a hole through the center to let a #6 screw pass, drilled another shallower hole just deep enough for a #6 nut to sit flush, then used structural epoxy to glue in the nut as well as to glue down the standoffs. It actually worked well. (The screws you see in the photo are temporary screws that have the threads covered with grease to keep the nut holes from getting filled with epoxy. Once the epoxy cured I removed those screws!)

Notice that I have a couple of not really parallel lines drawn on the door's fiberglass. I had to estimate where the arm rest would sit on the door. (I purchased the side stick option and that kit includes arm rests that get mounted to the door for resting one’s arm when flying with the side stick.) I couldn’t place any standoffs in that location since the arm rest pieces would cover them up.

Fuselage - Door - Cover Standoffs

These simple standoffs are structurally epoxied to the door and will be used to hold down the door cover.

And here is a photo of one of the installed door panel covers. Eventually this panel either gets painted (probably not) or covered with upholstery (probably). Those same stainless screws and decorative washers get used to hold the covered panels in place.

Fuselage - Door Panel Installed

The door panel is trimmed to size and is now screwed down!

Both doors are now mostly complete. I still have some finish work both on the inside frame around the window as well as the outside of the door around the window. More photos showing that process when I actually get around to doing it!

ui© John Trautschold 2018