For grounding the engine (and thus the starter and alternators) I decided to both install the Vans-recommended (OP-37) grounding straps, and one to the firewall grounding block - that gives me redundancy (it's still an electrically-dependent airplane), and has little chance of creating a ground loop. I drilled up the engine mount tabs for AN5 bolts (did I mention drilling hard steel in a hard-to-reach spot is a pain?), removed the powder coat from approximately the contact area of the ground strap terminal, and attached them:
Engine mount hole for grounding
Engine mount hole for grounding, with powder coat removed
Grounding strap between engine and engine mount
Grounding strap between engine and engine mount
Grounding strap between engine and firewall
We also used ProSeal to seal all the antennas - this made a bigger mess than expected and required quite a bit of cleanup to get a smooth fillet (a hint we didn't see or think of in time was to apply masking tape to the antennas to make a clean edge):
Sealed COM, Stormscope and ELT antennas
Sealed GPS antennas
Sealed TAS antenna
Sealed transponder antenna
Sealed GPS antenna before cleanup
Sealed GPS antenna after cleanup
We installed several more ClickBond fasteners, for the forward and tailcone servo wires, the top forward conduit wires (away from the screws that attach the cabin cover), and the remaining overhead console fasteners:
Heat tee servo wires secured to tunnel wall
Tailcone vent servo wires secured to the ceiling
After installing the fuel pump, we ran the remaining wires through the forward tunnel, connecting the GHA15 and the stick grip connectors on both sides:
Tunnel wiring secured around the fuel pump
Stick grip connectors secure in place in the tunnel
Stick grip connector coming out of the tunnel
There's not a lot left to do with avionics (well, at least compared to how much we've done so far) - once the tunnel is fully closed up, the alternator regulators are connected, and I update the firmware on the O2 sensor controller, the main things left will be securing the firewall-forward wiring, installing the overhead console inserts, and actually installing the panel and avionics permanently in place.
We re-ordered the coil packs to keep the cables a bit more organized:
Spark plug wires after changing the order of coil packs
I re-terminated the EFII ground lugs to use the ground tabs (and leave the larger bolt for the main engine grounding):
EFII ground wires connected to grounding block
After securing the sensor cables (oil pressure, oil temperature, fuel pressure, manifold pressure) inside the cockpit, I cut them to length and terminated them on the sensors - most of them were Metri-Pack 150 pull-to-seat connectors, which are slightly annoying since you have to crimp with the wires running through the connector:
Sensor Metri-Pack connector assembly
Sensor wires connected to FWF sensors
Oil temperature sensor connector
For securing the ignition and sensor wires around the cylinders, I couldn't find a bracket with the shape I wanted, so I 3D scanned the side of the engine and made one:
Spark plug wire bracket in 3D-scanned engine
Spark plug wire bracket design
A 3D-printed prototype showed that I had the right measurements off of the 3D scan, but it also seemed a bit flimsy, so I iterated to make a beefier version. Given the position of the injectors, I'm also not sure that top hole will be very useful:
Test spark plug wire bracket in place
Besides that, in favor of finishing the wiring behind the firewall, we organized, trimmed and terminated the alternator regulator wires that come from the FWF. This area is very annoying to access and I regret placing the regulators there already, but with some contortionism and a lot of patience, we got it more or less organized:
Original wiring mess near the alternator regulators
Wife doing contortionism to organize the alternator regulator wires
Slightly more organized wiring underneath the alternator regulators
We still need to replace the zipties with wax lacing and connect a couple more wires in that area.
With that side's lengths also set, I terminated the starter annunciator connection, with the inline resistor (installed in a Z shape with heatshrink, as the VP-X manual suggests), as well as the alternator field outputs:
Starter relay with all inputs connected
Next I'll make more of the spark plug wire brackets and finalize the rest of the FWF routing.
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 :)
