I made some more progress in this section. I started by trimming the control column mounts, which my new band saw blade made a trivial task:
Trimmed control column mounts
I then clecoed and match-drilled the forward bottom skin ribs, which go underneath the pilot/copilot floor:
Forward bottom skin and ribs
I attached the firewall parts to it and final-drilled their holes:
Firewall and tunnel attached to forward bottom skin and ribs
then finally added the floor panels:
Floor panels mounted to bottom skin/ribs/firewall
Floor planels mounted to bottom skin/ribs/firewall
I got a kit for a tunnel side access opening - its holes didn't line up with the pre-punched ones, so per their recommendation I shifted the whole thing forward and drilled new ones. This also required trimming off the corner of the doubler:
Tunnel access panel doubler match-drilled into place
A few days later, I received my Andair fuel valve:
Andair duplex fuel valve (extender not shown)
The small challenge with those is that they don't fit into the Van's-provided bracket, so I had to fabricate a new one - slightly annoying since the flanges are at an angle (the tunnel does not have parallel walls). I'll leave somewhat more detailed steps here, in case it's ever useful to anyone.
I started by laying out the existing one onto a new sheet, and then mirrored it to make room for all the holes:
Fuel valve bracket sketched on aluminum sheet, based on original part
I also realized the holes are not symmetrical, so it'd be tricky to transfer them onto the sheet, but luckily the face plate has the exact same alignment, so I used that:
Fuel valve face plate holes align with the valve holes exactly
Transferred holes from fuel valve face plate to sheet layout
I drilled the holes, including the center one with a unibit to 1-1/4", and adjusted slightly to make sure the valve fit:
Valve temporarily attached to new bracket web
This would make the web for a new bracket, and I also cut two 2" x 2.5" rectangles for the flanges. I bent them using a wood block and rubber mallet, then transferred the holes from the original bracket onto them, making them exactly .064" lower (so that the web, coming atop the flanges, would be at the same height):
Transferring holes from original bracket to new bracket flanges
Side view of hole alignment between old and new bracket parts
I picked two points at reasonable edge distances on the "webs" of both flanges, and drilled holes for nutplates there:
Nutplate holes on new fuel valve bracket flange parts
With those loose parts, I clecoed the flanges to the tunnel, laid the web on top, and then clecoed the original part just above them, to get the same spacing:
Fuel valve and web part laying onto flange parts, with original bracket above it
I started by visually aligning the center shaft with the original bracket's hole, and clamped the web to the flanges:
Alignment of Andair fuel valve center shaft with center hole of the original bracket
I verified by putting the tunnel cover on and checking that the center was aligned (minus parallax) with the original hole meant for the valve:
Tunnel cover on top of tunnel, for valve alignment
Valve shaft alignment through the cover hole
With that, I went on to match-drill the nutplate screw holes onto the web:
Match-drilled web and flanges for the new valve bracket, seen from the top
Match-drilled web and flanges for the new valve bracket, seen from the bottom
I checked that it overall matches the original part in size and flange angles:
New valve bracket, with original bracket on top to check for matching angles and distances
Then finally, I countersunk the nutplate holes, deburred and clecoed the whole part back in the tunnel:
Final-drilled, deburred and countersunk parts for new valve bracket
New valve bracket mounted into place
Finally, I attached the forward center section bulkhead to the forward ribs and match-drilled them:
Center section bulkhead clecoed to forward ribs and skin
Next I'll start disassembling and deburring all these parts, then priming and riveting them.
Time lapse:
Total forward-fuselage ribs and bulkheads rivets: 0 Total forward-fuselage ribs and bulkheads time: 23.6h
I started riveting the mid-fuselage ribs that I had already primed:
Forward mid-fuselage ribs riveted to aft center section bulkhead
I specifically avoided riveting the two inboard ribs on the aft end, so that I can insert the heat tee and flap motor bracket later, when they're primed.
Most rivets were trivial, though some are later hidden behind other parts:
Flush rivets hidden behind other parts
Rear bulkhead side channel riveted to rear spar
I clecoed the other ribs to see what I'll need to do for passing the conduits to the tailcone:
Simulated conduit runs through the baggage area ribs
With that, I concluded that I also needed to use the lower hole (that goes below the step mountain bracket), so I enlarged those to 3/4":
Enlarged fuselage bulkhead hole for a conduit
For the flap motor, I'm using a non-standard motor which has a built-in position sensor and automatically stops at the end of the travel, so I first mounted the standard motor and found the right angles for the extremes:
Original flap motor at the retracted position
Fully-extended flap position marking
I then mounted the new motor and found a position it can sit in which will give roughly the same two extremes:
New flap motor matching the fully-extended flap angle
Next I have a lot of deburring to do so I can prime and rivet the rest of the ribs.
Time lapse:
Total mid-fuselage ribs rivets: 196 Total mid-fuselage ribs time: 40.5h
It's been a long time coming, but the first section of the fuselage kit is complete!
I bolted and riveted the mid seat rail supports to the forward center section:
Mid seat rail supports riveted to forward center section
then the forward center section bulkheads:
Completed forward center section
Similarly, for the aft center section, which has aft seat rail supports:
Aft center section bulkhead sides and aft seat rail support
and the hat stiffeners:
Center section hat stiffener
Complete aft center section bulkheads
Did I say it's complete? I lied - there's actually one small part left - the L-shaped bar at the end of the center section didn't fit (the drilling is done in the inverted position and I forgot to try it out and grind it to fit :/ ) - I'm delaying that until the next batch of primer.
Stiffener angle that needs grinding down
Time lapse:
Total mid-fuselage bulkhead rivets: 617 Total mid-fuselage bulkhead time: 59.2h
I deburred all the mid-fuselage ribs to prepare for primer, then primed them:
Priming various parts including mid-fuselage ribs
Some primed mid-fuselage ribs
I riveted the outboard seat ribs and their intercostals:
Outboard seat rib
Outboard seat ribs fully riveted
then the inboard seat ribs:
Inboard seat rib partially riveted
Inboard seat ribs clecoed to aft center section
I haven't touched the bottom skin yet - those are the holes I'll work on after primer, to ensure exact alignment (this is too many interlocked parts accumulating small differences in thickness between the plastic and the primer). This means priming the rest of the ribs, which in turn means defining what modifications to them I need for the conduits.
Time lapse:
Total mid-fuselage ribs rivets: 132 Total mid-fuselage ribs time: 31.9h
We primed all the mid-fuselage bulkhead (and some of the mid-fuselage rib) parts:
Washing parts for primer with Prekote
Priming parts
Primed mid-fuselage (bulkhead and ribs) parts
More primed mid-fuselage (bulkhead and ribs) parts
Even more primed mid-fuselage parts
and then started riveting them:
Riveted mid-seat rail supports
Center section bulkhead with the doubler installed
Rear side of the center section bulkhead doubler
Mid-seat rail supports in position
Most center section parts are also bolted on, so I torqued those properly:
Torquing mid-seat rail supports to the center section
I did the same for the aft center bulkhead:
Aft center-section bulkheads with doublers installed
After clecoing those parts to the bulkhead, I torqued all the bolts:
Aft center-section bulkheads assembled with bolts torqued
and riveted the plastic wear strip:
Wear strip pop-riveted to aft center section bulkhead
I riveted the rear spar side channels:
Rear spar bulkhead side channels with gussets and nutplates installed
and started riveting the rear spar attach bar, only to realize halfway into it that the shop heads were supposed to go on the other side :(
Rear spar attach bar, with rivets on the wrong side :(
After replacing those rivets, I finished riveting the spar attach bars and the idler arm brackets:
Riveted rear spar
Finally, I riveted the fuselage bulkhead (rearmost bulkhead, just before the baggage compartment), which has surprisingly little done to it at this stage:
Riveted fuselage bulkhead
Time lapse:
Total mid-fuselage bulkhead rivets: 413 Total mid-fuselage bulkehad time: 53.6h
