Oil cooler mount modifications

I started section FF1 even before having the FWF kit by assembling the oil cooler box (which I got along with the finish kit).

Oil cooler clecoed to itself

Riveted oil cooler, clecoed to the firewall

I went with one size higher for the actual cooler - the Airflow Systems 2007X instead of 2006X - so I had to modify the mount to fit, by removing the top row of nutplates and attaching them to an angle instead:

Oil cooler mount on top of the oil cooler, for measuring hole positions

Trimmed aluminum angle for attaching nutplates to the top of the oil cooler mount

Oil cooler mount with nutplates on an angle on top of it

Then, per Airflow's instructions, I added a tuning vane to reduce the air pressure difference between the two halves of the cooler, and attached it in place with angles:

Adjusting the tuning vane's position to the center of both openings

Tuning vane with angles for attachment

Tuning vane riveted inside the oil cooler mount using angles

Tuning vane riveted inside the oil cooler mount

Now I'm back to waiting for the engine to arrive before I can continue this section (I've already ordered it from Barrett, a few months ago before the price increases :) ).

Time lapse:

Total engine installation rivets: 43
Total engine installation time: 7.6h

Baggage area O2 mount box

I made progress on the EDS-4IP cylinder install, first by attaching the brackets:

O2 cylinder mount brackets and straps in place

I got the loaner O2 cylinder from MH, and checked that it was properly aligned - but also realized I had the wrong metal straps, so I'm exchanging those for shorter ones:

Mountain High O2 cylinder strapped in place

I designed a box to protect it (and even allow lightweight items to be on top), and had it laser-cut and CNC-bent:

Laser-cut, CNC-bent parts upon arrival from SCS

That almost fit well, but was too close up against the rear seat, and made me realize I had a twist in the right baggage cover that needed to be accounted for in the design:

First version of the O2 box, sitting in a tight fit

Significant angle difference on top cover of the O2 box due to twisting

Small gap at the aft portion of the O2 box

Tight fit of the O2 box against the rear seat

Also, the company that CNC-bent them for me apparently doesn't have enough precision for making matching parts (I asked, they basically said that's how it is), so for the second iteration I switched to Oshcut, which was a bit more expensive, but parts were spot on:

Misaligned holes made by SendCutSend

Space inside the box for the cylinder attachment

Second version of the O2 box sitting in place

that was almost perfect, except I forgot to account for the different thicknesses, leaving a tiny gap - so I adjusted again and got just the front lid done again, which fixed it.

Much smaller gap on version 2 of the O2 box

I then match-drilled the box onto the right baggage cover, drilled for nutplates on the cover, and deburred everything:

O2 box (version 3) match-drilled into place

Right baggage cover drilled for nutplates to attach the O2 box

Last on the box, I added a couple of stiffener ribs to support a little bit of weight on top - I made sure to position them away from the attachment straps:

O2 box ribs match-drilled into place

On another baggage area leftover item, I had one rivet left to attach the upper baggage door seal channel, which unfortunately required removing the bolts that join the longerons together - since I had the top forward tailcone skin off, I remove them and set the rivet:

Last, hard-to-reach rivet attaching the upper baggage door seal channel

Next will be applying primer on the O2 box parts and riveting it all together.

Time lapse:

Total baggage area rivets: 637
Total baggage area time: 60.6h

Cabin cover finishing started

We removed the cabin cover for the last time to finish it up.

There was a pretty big gap between the cabin cover and the overhead console (about 1/4") - I sanded the cabin cover surface a bunch to reduce it, but it became clear that there was no way I was going to close the gap fully without making the fiberglass pretty thin (or getting to the foam core), so instead we built up a "shim" down from the cabin cover to meet the console:

Gap between the cabin cover and overhead console

Laying up fiberglass shim for the overhead console

Overhead console in place to form shim

Overhead console shim after curing

No more gap between the cabin cover and overhead console

With that, I finished drilling the overhead console to attach it (when we previously detected the gap, we had only made a couple of holes - just enough to keep it in place but not enough for the attachment later):

Overhead console clecoed in place

I also made holes for running wires between the console and the switch pod:

Wiring holes on the overhead console

Wiring holes with the switch pod in place

I also attached the ventilation flanges for the overhead console, and riveted the baggage bulkhead channel to the top bulkhead - this may make it a bit harder to rivet the tailcone top skin later, but I didn't really have a choice due to the ordering of attachments:

Overhead ventilation flanges riveted in place

Finally, I started sanding the uncovered parts of the cabin cover, but that's one large exercise in patience, so there's a lot more to do there.

Time lapse:

Total cabin cover rivets: 64
Total cabin cover time: 77h

Interior covers priming and painting

I installed the remaining nutplates for attaching the interior panels:

Interior panel nutplates installed

It was then time to prime and paint most other cover panels:

Applying primer to cover parts

Getting soaked by a burst water hose while washing parts with Prekote

Primed and painted cover parts

I riveted the nutplates and splice plates that go on those:

Painted/primed mid cabin side covers with nutplates on

All cover panels in place

Painted seat back brace closeout, with O2 fill valve brackets riveted in place

Time lapse:

Total access cover and floor panel rivets: 596
Total access cover and floor panel time: 44.1h

Tailcone avionics and battery mounting

Before joining the tailcone to the fuselage, I cut and drilled a tray for avionics (to be refined later when I actually have the avionics to mount):

Match-drilling the tailcone rails to the avionics rack

Avionics rack screwed in place

With my intention of using 2 EarthX batteries, I had to figure out how to attach them (the standard bracket doesn't do a good job since the batteries are smaller).

Physical parts for the battery installation

 I took that as an excuse to learn Fusion 360, model the parts, and sketch some ideas there:

I started with some custom brackets to attach it to the existing structure, unmodified:

Higher "shelf" for the second battery

Battery hold-down bracket that only attaches the EarthX vertically

Battery hold-down bracket that fits the EarthX shape all around it

Those would work, but they add some weight and are not really "elegant" solutions, so I tried a few options with EarthX's official box (which I also had to model):

Attaching the batteries with the EarthX official box

Attaching the batteries with the EarthX official box, laterally

(if these models are useful to anyone, you can find them here)

I showed this to Van's support and they didn't like the idea of the underlying ribs being loaded asymmetrically, so I ended up cutting both sides and using their battery boxes:

EarthX battery boxes

The goal is to double-flush rivet them (with a spacer inbetween), so I had to do some testing on thicknesses and rivet lengths before cutting the spacers (ended up with 0.063" for the spacers):

Double-flush rivet thickness testing

Battery boxes clecoed together with spacers

Machine-countersunk battery box holes

I cut of the sides of the original battery mount and attached the new joined boxes to it:

Modified battery mount

Battery boxes on the new battery mount

After primer, I'll rivet this all together and effectively complete section 10.

Time lapse:

Total tailcone rivets: 1866
Total tailcone time: 231.8h