Fuel tanks tested and attached

Before moving, we wanted to put the wing parts together, such as attaching the tanks back in place - for that, we had to leak-test them.

We used a product called Snoop (thanks once again VAF!).

Applying snoop to the rivet lines
Applying Snoop to the sealed baffle
We weren't finding any leaks and I kept wondering if we were doing it right, but then Snoop proved that it really works - there was a tiny bit of air leaking from the return line cap (which was temporary and thus not sealed), and it produced a lot of bubbles:

Bubbles from the fuel return cap (underneath it)

We're looking forward to those camping trips, sleeping under the airplane :)
We then attached the tanks and moved both wings onto the same wing stand:

Attaching the left fuel tank

Attaching the right fuel tank

Tanks attached
We then realized that there was some skin overlap between the tank and the other skins which was making them buckle:

Buckled skin which needs to be trimmed down to match the inboard skin

Buckled skin which needs to be trimmed down to match the leading edge skin
This was just a couple of days before moving, though, and we didn't have the time to fix it then. The only remaining step is to fix that, but it involves removing the tanks, filing down the skin edges, and then attaching them again.

Time lapse:


Total fuel tank time: 14.2h
Total fuel tank rivets: 30 

We're back (some bottom wing skin progress)

I've finally made some small progress on the bottom wing skins at the new house :) That said, I'll likely spend some time posting progress that happened before we moved that I hadn't had the time to upload yet.

The new workshop is set up, full with a new compressor:

New workshop
New compressor
I spent some time deburring the outboard bottom wing skins at the old place and started preparing the inboard nutplate holes - more than 6 months later, at the new place, I finally finished those and installed the nutplates:

Inboard nutplates installed
Dimpling the aftmost screw hole was a challenge, since the dimple die wouldn't fit there - I took a #8 screw dimple die and simply ground down the side until it fit:

Customized #8 dimple die which will fit to dimple the aftmost inboard nutplate screw hole

Small progress, but I'm back to work nonetheless.

Time lapse:


Total bottom wing skin time: 40h
Total bottom wing skin rivets: 430

We've moved!

We finally moved to the new house today.
I seriously considered the suggestion on VAF to move the airplane myself, but since we were hiring movers for a lot of other stuff anyway, we just had them take it. They did a pretty good job, and the only thing I had to ask them to do differently was to lay my flaps flat on the truck floor instead of on their trailing edges.
Garage all packed up and ready for moving!
Loading the wings onto the truck
Loading the tailcone
Goodbye, old workshop! You served me well, but I shall not miss you.
Unloading the (intact) wings
Moving the wings into the new garage
New workshop full of parts
A few of the smaller parts will still need to be taken by car (ailerons, vertical stabilizer, rudder, etc.), but all the large parts and a lot of the small stuff is already there.

Now on to putting the workshop together again to build on!

Fuel tank assembly complete

The tank comes mostly assembled, with a few finishing items not yet done.

The first task was to remove the tanks, which was easy but time-consuming (lots of screws and bolts):
Tank removed from the right wing
riveting the bearing:
Bearing riveted to right tank
I installed the skin nutplates, including those that are only called for much later in section 44 (didn't find a reason not to):
Nutplates riveted to right tank
I bent and cut the fuel sender arms, only to find that I, like others, had screwed up and cut it too short without realizing the arm is supposed to go through the sender. Ordered new arms, re-did it - correctly this time:
Fuel sender arms after bending

Fuel senders, VA-261 pickups, drain and other hardware for the tank
I read up a little more on the fuel system and realized that, if I decide to use a FADEC, I may need a fuel return line. Much easier to do it before installing the tank, so I did some careful planning - some people from VAF pointed out that it can't be too far aft or it'll get in the way of the wing attachment. I got two more VA-141 brackets for this, and used a 3/8" NPT tap to make sure I could screw VA-261s in from the other side. I then used those to drill the holes on the side of the tank, next to the vent line:
Holes drilled for fuel return line bracket on left tank
We did the drilling with a vacuum cleaner extension (piece of conduit taped to the tip of the vacuum) strategically placed to catch aluminum bits, which greatly minimized the mess inside the tank, but we still had to later move that extension around to clean up all the bits that flew around the tank.

When I drilled the left one, I realized I, too, had made a small mistake - notice the J-channel from the tank's structure shows through the hole - the hole was too close to it, so I had to shave off the corner of the J-channel to ensure the VA-261 would still fit.

On the second tank, I drilled the hole a bit further to the side, and instead trimmed the bracket itself to fit, this time hitting no obstacles inside:
Holes for fuel return line bracket
Trimmed VA-141 bracket for fuel return line
Finally, I installed the senders, return bracket, pickup, and drain, using tank sealant and thread-locking sealant. For the fuel return brackets, I used CR3212-4-2 rivets:
Fuel return bracket, fuel level sender and fuel pickup installed on left tank

Fuel return bracket, fuel level sender, fuel pickup and drain installed on left tank

Right fuel tank with all plugs and brackets installed
We then installed the Newton fuel caps - even in the garage, the Van's caps were annoying enough to open and close to make me want to replace them:

Cleaning the excess sealant from the fuel cap bracket the best we could

Newton fuel cap installed (needs some cleanup afterwards)
Last but not least, someone at VAF called my attention to the fact that I hadn't left a ring terminal around one of the fuel sender screws, so after the sealant cured I checked the ground continuity between the fuel sender plate and the skin, and it seems to be conducting just fine.

Among the next steps are leak-checking the tanks and reattaching them to the wing spars.

Time lapse:


Total fuel tank time: 12.1h
Total fuel tank rivets: 30

Tailcone mod chemicals

Over the last few months, we did some small tailcone mod tasks.
We used Clickbond CB9120s for running conduit through the tailcone:
including one vertically at the bulkhead to run the pitch trim/ELT cable down:
Vertical wire bundle attachment in place

Vertical wire bundle attachment for trim motor / ELT wires

Conduit attachment brackets in place along tailcone
More recently, since the sealant I purchased was getting close to expiration, we attached the NACA vents and static ports with sealant:
Applying sealant to NACA vents
NACA vent clecoed in place with sealant
NACA vent clecoed in place with sealant
Static port clecoed in place with sealant
Riveting those will have to wait - I was using a borrowed compressor which I had to return, and I won't get a new one until we're settled in the new house.

Time lapse:


Total tailcone time: 220.9h
Total tailcone rivets: 1826

Building paused (for a good cause)

This is not the usual airplane-building post. The good news is that I've bought a house!!
This means several things: it means that I've spent the last month doing copious amounts of paperwork, that I'll spend the next two months preparing to move and moving, and most importantly it means that I can't afford to order the fuselage kit right now, so the building is paused for the time being, and I'll post just a few videos that I already had in the queue.

 It also means that I'll have a larger garage for working on the RV though, so stay tuned :)

Bottom wing skins: pitot mount and flap gap fairing riveting

I replaced the bad rivets behind the inboard bottom wing skin with CR3212s (and one CR3242) as recommended by Van's, for much better results:
Inboard flap gap fairing rivets re-done with CherryMax
I also used MSP-42s for the other rivets that would be nearly impossible to reach with a bucking bar:
Pop rivets for the inboard portion of the flap gap fairing
Pop rivets for the inboard portion of the flap gap fairing
as well as the rivet that sits too close to the bracket from SB16-03-28 (which Van's was very kind to address during the quickbuild process, but left me without access to buck that rivet):
Pop rivets near the SB16-03-28 bracket
My OCD side dislikes having two types of rivets on the same line, but there's no way I'm going to remove and re-set all the solid rivets :)

I then continued with the Gretz pitot mount installation by match-drilling 3 of the backing plate holes through the skin from the inside, which was annoying and required 2 people - one with the drill and another with a mirror to position the drill bit into the hole using a mirror:
Finding pitot mount backing plate hole positions from the inside with a mirror
Pitot mount backing plate match-drilled to skin from the inside
With the two holes near the rib, I positioned the rib bracket against the backing plate and rib (using the mirror to get the right height), then match-drilled again through it. I removed the skin and match-drilled the other 2 holes of the bracket through the backing plate and the 3 1/8" holes through the rib:
Rib bracket match-drilled to backing plate
I clecoed the backing plate to the skin again, match-drilled the remaining holes and marked the main mast hole:
Gretz pitot mount backing plate match-drilled to skin
To cut off the mast hole, I then used the Swiss technique - drill it like a Swiss cheese :)
Mast hole marked
"Swiss cheese" of holes to cut off the mast hole
I then finished it off with the dremel (cutting and then grinding), through the skin as well as backing plate and washer plate (which I had to trim down for the rib bracket to fit):
Main section of the mast hole removed
Backing plate and trimmed washer plate also grinded down to fit the mast
Gretz pitot mount in plate
Gretz pitot mount in place
I then test-fit it again in the wing, and also determined that there's enough wire in the heat regulator box to reach it from a couple of ribs inboard (which is good to minimize interference with the NAV antenna and magnetometer on the wingtip):
Wires from pitot heat regulator to pitot tube
I also drilled and deburred the other cover plates:
Drilled and deburred cover plates
It was then time to deburr the hundreds of holes on the bottom skins, as well as their edges and the corresponding holes on the ribs - no photos of that, but it's most of the time in the time lapse below.

Time lapse:


Total bottom skins time: 34.9h
Total bottom skins rivets: 406

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