Cabin cover sanding

To make the upper portion of the bulkheads nest properly against the cabin cover, I marked the contact area between them, and sanded that flat:

Bulkhead attachment surface after only partial trimming

Flattened bulkhead attachment surface

For the door inside flanges, I read several reports of people that trimmed too much off and had to rebuild it (VAF post) and recommendations to not fully trim it until I'm fitting the doors (VAF post 1, post 2), so I trimmed it but gave ample margin from the suggested 1" from the bottom, and from the side scribe lines:

Markings for cutting the inside door flanges, well below the target 1" distance from the bevel

Plenty of margin between the scribe line and my cut

Inside door flange, trimmed far from the scribe line

I looked at several photos from other builders (like these and these) and they all seem to have trimmed more than this, so I should be fine with final-trimming later with the doors. I do plan to use the McMaster-Carr seal (post).

I realize this means there'll probably be a second cut later to adjust these, but at least I can drill and countersink the holes along the flange without interference.

Towards the end of this process, I found the the Dremel rotary tool actually cuts the fiberglass much more easily than the oscillating tool, and while it makes a bigger mess, it's basically a "directed jet" of fiberglass dust, so as long as I stay away from it, I actually get less fiberglass on myself:

"Working with fiberglass is not messy at all", said no one over

Besides that, I had several more passes of trimming the various flanges to fit well.

Cabin cover fitting well on the fuselage

Now that it fits properly, I can start drilling the attachment holes.

P.S.: OMG I hate fiberglass. How do people find it fun to build entire airplanes out of this?

Time lapse:

Total cabin cover rivets: 0
Total cabin cover time: 27.6h

Cabin cover started

We got started on section 43, the cabin cover, which is the largest fiberglass part of the build. It starts with making some markings for later drilling the door flange:

Cabin cover door flange hole reference markings

It quickly jumps to trimming and sanding the cover. We trimmed the edges with a Dremel oscilating tool, then sanded with a combination of an orbital sander, sanding block and Dremel rotating tool, and that has taken almost 10 hours of work so far:

Trimming the mid-side skin flange on the cabin cover

Sanding the cover flanges

And more sanding of the flanges

The corners of the door flange need some additional sanding and a notch to fit around the mid-cabin deck flange:

Notch on the corner of the door flange

After 5 attempts and many hours sanding and trimming, the cabin cover finally fit properly:

Cabin cover fitted against side skin and tailcone bulkhead

Mid-side skin flange clearing the longeron

Tailcone forward top skin fitted over the cabin cover

Victory! Cabin cover fits!

In the process, I also found that the scribe lines are pretty much useless, since they don't match at all the required dimensions:

Trim line doesn't match the dimension on the plans

There's still a lot more sanding and trimming to be done - I haven't trimmed the other window flange, the inside of the door flanges, or the windshield flange, and the tailcone top skin flange could use some slight sanding to not push against the bulkhead.

Time lapse:

Total cabin cover rivets: 0
Total cabin cover time: 16.3h

Brake lines done

I got the fuel hoses from Aircraft Specialty, and installed the one that's done in this section, and torqued all the fittings:

This involved enlarging the system bracket holes a little more (to 5/8"), and splitting the AN931-6-10 grommets so I could put them around the hoses (I also took the opportunity and did the same for the fuel hose holes, to 7/16" for AN931-7-11 grommets).

Time lapse:

Total brake line rivets: 8
Total brake line time: 11.0h

Forward fuselage access panels (OP-43)

I was planning on adding access panels forward of the windshield anyway (seems to be a common mod), so I was happy that Van's released an official OP kit for this (OP-43). It works pretty much like all access panels - match-drill the doublers, cut the skin, then file it all down until it fits well:

Doublers and covers atop the forward fuselage top skin

Forward fuselage top skin match-drilled for the doublers and marked for cutting

Forward fuselage top skin after cutting, with doublers and cover on

Whenever I do the next batch of primer, I'll include these so I can start riveting them (though I won't prime for rivet the top forward skin for quite some time still).

Time lapse:

Total forward fuselage access panel rivets: 0
Total forward fuselage access panel time: 4.3h

Brake lines mostly done

We started bending the brake lines - it was at first an exercise in patience, and our first attempt was definitely not good :)

Very irregular curve on our first attempt on making the brake line (left), vs a better result on the second (right)
Kink made during our first attempt on making a brake line

We persisted, and the second and third attempts were actually quite decent:

Firewall fittings connected to rigid brake lines

Rigid brake line bends
Rigid brake lines going down the firewall
Rigid brake lines going aft through the tunnel
With that done, I dimpled and riveted the ducted flanges to the tunnel:

Ducted flange riveted to the tunnel above the brake lines

For the tunnel-to-gear tubing (as well as the pedal tubing in section 38), I'm just getting the lines made by Aircraft Specialty, plus I need to torque all these fittings, so I'll have a short follow-up, but other than that this section is complete.

Time lapse:

Total brake line rivets: 8
Total brake line time: 6.5h

Tailcone attachment complete

The next step in the tailcone attachment was, well, to detach it :) so I did:

Tailcone detached from the fuselage

I added the Panduit conduit mounts to the lightening holes:

Match-drilling Panduit conduit mounts to the bulkhead

The sequence here was to attach the tailcone, the baggage/rear seat floors, drill everything needed (e.g. door, floors, covers, etc.) while the cone was attached, then detach it, so that I could do a single larger batch of primer and need less post-primer drilling.

After that batch of primer, I riveted the bulkheads together:

Bulkheads riveted together and to the Panduit conduit mounts, after primer and paint
and attached those to the fuselage - the plans call for attaching it to the tailcone first, but I figured this would be easier since there are more rivets on the baggage rib attachment:

Bulkhead riveted to the baggage ribs
With this, we finally attached the cone for good:

Tailcone clecoed to the fuselage once again

then riveted it:

Left side skin riveted around the baggage door opening

Fuselage and tailcone longerons bolted together

Tailcone (left) and fuselage (right) bottom skins riveted together

About going out of order and it being easier this way - wellll, at the very end, when we got to the part that would normally be done without the fuselage in place, we screwed up badly on one rivet and had to upsize it. We tried setting the surrounding ones but they were starting to look really bad too, so we removed it all and switched to CherryMax (CR3213-4-2, CR3243-4-2 and a CR3243-5-2 depending on the hole):

Enlarged hole from removing a bad rivet :(
That face you make when you badly enlarged a hole while removing the rivet :)
Fixed bellcrank rib attachment, using CherryMax rivets

With this, section 32 is complete!

Time lapse:

Total tailcone attachment rivets: 236
Total tailcone attachment time: 22.8h

Baggage area riveting

I started riveting the baggage area. The nutplate rivets on the upper baggage seal channel were going to be just impossible to buck, so I used Cherry nutplate rivets (CCR series) instead:

Upper baggage seal channel nutplates riveted with cherry rivets

Painted and riveted upper baggage seal channel

I attached nutplates in most places that called for them, except those that would attach them through multiple parts:

Baggage bulkhead corrugations with wear blocks and nutplates on

Rear seat floors with nutplates on (some rivets were replaced after this)

Baggage floor inspection panel doublers with nutplates on

Baggage floors with O2 tank attachment doublers, inspection panel doublers and nutplates on

We then installed the Clickbond mounts for running the conduits underneath the baggage area:

Sanding Clickbond mount attachment areas, protected with tape
Sanded areas for Clickbond mounts
Clickbond mounts attached to bottom skin
All Clickbond mounts attached to bottom skin for conduits
Since we were doing that, we also installed a few of the Clickbond mounts farther forward:

Clickbond mount for running wires into the wing connectors
Clickbond mounts for running wires across the rear seats

One of the Panduit conduit brackets ended up being drilled too low :( so to remedy that without having to drill yet more holes, I made a shim for it:

Panduit conduit bracket and 3D-printed shim
3D-printed shim firmly attached to Panduit bracket
I can't, of course, claim that I got those dimensions right on the first try, so it took a few attempts:

All 8 attempts to get the Panduit shim right
Panduit bracket with shim, riveted in place
Checking conduit clearance with Panduit bracket and shim

Now I'm just waiting for the GripLockTies to attach the conduits, before I rivet the floors for good - once that's done, finishing multiple other sections (like the baggage door) will also be possible.

Time lapse:

Total baggage area rivets:
Total baggage area time: