We started work on the bottom windshield fairing, following the EAA method, by sanding the metal and the plexiglass, applying structural adhesive to the surfaces, then applying a small layer of filler to the joint (being careful to not let much of it go inside):
Windshield joint with sanded metal and plexiglass
Applying filler to windshield joint
Windshield joint with adhesive and filler applied
It was then time to apply the "fake prepreg" strips of fiberglass - a 2.25" strip with 2 layers of fiberglass. To make it easier to work with, we chose to split it roughly at the middle, with each layer being a couple inches offset to make an overlap near the center:
Laying up fiberglass on top of the prepreg plastic
Pre-pregging by squeezing the resin into every part of the fiberglass
Cutting the prepreg into 2.25" x 3.5' offset strips
Windshield joint fiberglass after curing
Once that cured, it was time to apply another layer of filler (a little thicker this time, meant to give it shape), followed by another couple layers of prepreg fiberglass:
Windshield joint after sanding the first layer of fiberglass
Patricia performing "precision guesswork", shaping the filler to follow a nice curve
Windshield joint with filler applied to its full extent
Windshield joint with a second fiberglass layup applied
The fiberglass overlap with the column needed some significant sanding to make a smooth ramp down to the door surface:
Windshield joint, sanded where it meets the column
It was then time to apply the Aeropoxy Light filler, which is a very thick but also very light paste:
Mixing Aeropoxy Light filler
Aeropoxy Light (with black tint) applied to the windshield joint
Sanding the Aeropoxy left some clear high and low spots, which were then filled with polyester icing, which was itself sanded and primed, then the primer was fine-sanded smooth, yielding a nice finished fairing:
Sanding Aeropoxy Light
Sanded Aeropoxy showing some high and low spots
Polyester icing applied to fill irregularities in the surface
Finished windshield fairing, primed and sanded
We also filled the gap behind the fairing where the windshield meets the cabin cover column, with black-tinted resin, to reduce the chance of future cracking of the fairing:
Gap between the windshield fairing, the windshield and the cabin cover column
The minor imperfections around the transition will become Jonathan's problem :)
We started the windshield installation by carefully determining the centerline of the airplane, and matching that to the center of the windshield:
Using the laser to find the center of the fuselage, to align the windshield
That is, until we realized the center of the windshield is BS and totally irrelevant given the irregular shape :) and instead we simply adjusted it to a position that seemed to make more sense and look good, trimming the edges as we went until we got a gap of less than 3/32" all around the cabin cover flange. We then marked it and trimmed down to get the actual consistent 3/32" gap, using arbitrary markings to realign:
Alignment markings on the windshield and fuselage
Trimming the windshield with a sanding disk
We sanded the cabin cover flange until the fiber was exposed (same as for the windows), and did some more minor adjustment of the flange and windshield edges to keep a consistent 3/32" gap:
Fuselage taped up for sanding the windshield flange
We then taped up the windshield - the top following the Silpruf process, and the bottom following EAA's process:
Windshield with external tapes applied to it
Windshield with interior tapes applies to it
Fully-trimmed windshield held in place by clecos and clamps
With the window ready to attach, I also fabricated and attached the 5 clips that are supposed to hold it in place:
Metal clips for holding the windshield
Windshield held in place by metal clips
We then followed the same process as the windows' for the top edge of the windshield, applying Silpruf, installing spacers, waiting for 12h, then trimming the spacers and gluing it in:
Windshield with a first layer of Silpruf applied to the top edge
Windshield attached to the top flange with Silpruf
We had tried to keep the cleco holes relatively shallow to reduce the change of hitting the conduit behind them, and that worked fine initially but during that final attachment some clecos just didn't take - cleaning off the Silpruf around them and from the clecos themselves helped (I guess the Silpruf was acting as a lubricant and making the clecos slide out?), but we also added some clamps to lower the pressure against the clecos.
We also already marked the edges of the fiberglass fairing, which is what we'll tackle next:
Bottom windshield fairing space taped up for fiberglass layup
After the Silpruf on the rear windows had cured, we removed the clecos, and they held!
Rear window attached in place, without clecos holding it
With this, we repeated the same process for the door windows, startin with trimming the windows and sanding the door flanges (only enough for the fibers to show):
Door window flange, sanded until the fibers show
We trimmed the windows to leave a 3/32" gap, then drilled those gaps for clecos (and unlike the rear windows, on these the holes did not go all the way through, which is convenient since finishing will be easier (no repainting the inside):
Right door window held in place with clecos, after trimming
We taped up the area where we didn't want Silpruf, and attached spacers with RTV:
Left door with protective tape and spacers glued on
A first layer of Silpruf is applied to the end, then let cure for ~24h:
Applying Silpruf to the door window edges
Spreading Silpruf into a thin layer on the door window edges
Right door window with Silpruf applied, and the first tape removed
We then apply a second thin layer of Silpruf to the window, and a thick layer to the window flanges:
Applying Silpruf to the right door flange
Right door window set in place with Silpruf, held at the right depth by clecos
Left door window set in place with Silpruf, held at the right depth by clecos
We had a bit too much squeezeout on some of the inside edge, and too little on other parts, so a lot of adjusting of the inside finish had to be done:
Cleaning up the excess Silpruf that squeezed out of the inside
After removing all the Silpruf-cutting tapes, the end result was pretty good:
Right door window installed in place, after the inside edges were cleaned up and the tape removed
With this, the only part of section 45 remaining is installing the (dreaded) windshield.
