It’s been a couple of weeks since I posted any progress on the fuselage.  Doesn’t mean I haven’t been working, I’ve just been too busy to update the website.  Here’s a quick collection of everything I’ve done recently.

Once I knew I could connect the fuel pump to the fuel selector, I positioned and drilled the forward tunnel cover to the center floor stiffeners.  The plans only call for two fasteners on each side, but I added another to accommodate some reinforcements for the fuel pump support structure (more on that below).

The’s nothing particularly difficult about drilling these holes, except that the bottom surface of the cover needs to be 15/16″ above the floor.  Some spacers made from scrap 2″x4″ made that relatively easy.  I also used a bit of scrap 1/8″ aluminum angle as a drill jig to make sure the holes were drilled at the right height above the floor..big thanks to Mike Bullock for that idea.  And for me at least, angle drills are hard to position precisely…the drill jig helped with that as well.

Andair publishes a really nice set of plans for a reinforcement structure to support their fuel pump and filter on the forward tunnel.  Problem is, their heavy 1/8″ support angles completely block off area under the tunnel, and make it impossible to run wiring through that area – and they’re complete overkill structurally for a pump that barely weighs a pound.

After doing some research online, I found other builders were using 0.63″ angle and plate to reinforce the pump mounting area.  And since Van’s mounting bracket for the Airflow Performance pump and filter is made from a similar gauge of aluminum, I decided to go with the reinforcement plate and angles.

Here’s the plate and angles match-drilled to the bottom of the tunnel cover.  I’m very happy with the way this turned out.

Knowing that the pump and filter were in a good location, and with the mounting holes drilled, I opened up a rectangular area ahead of the pump per Andair’s plans, to allow the fuel line to route under the tunnel cover to the firewall.

The only thing left to do in this area was to match-drill the pump cover to the tunnel and fuel valve cover.  Nothing too difficult here, just need to make sure the pump cover flanges are positioned neatly along the tunnel sides.

There’s a portion of the tunnel cover that acts as a heater plenum, and it’s attached to the firewall oil filter cutout with #8 screws and platenuts.  I’d forgotten what a pain in the ass it is to drill stainless steel…the screw holes aren’t beautiful, but they’re functional.

The final bit of work to do in the forward fuse was mounting the flap actuator, motor and support structure.

I haven’t touched this weldment and supports in a couple of years, when I match-drilled the UHMW supports to the seat back bulkhead.  One less part in the pile…

Van’s issued a service bulletin several years ago requesting that builders safety-wire the flap motor rod end to make sure it doesn’t unscrew itself, thus making the flaps inoperative.  Per instructions, I drilled a hole for the safety wire.  I was afraid this would turn into an expensive mess, but the center punch and a #50 drill bit made quick work of it.  I know, the picture is fuzzy…sorry.

I had a special visitor during the flap marathon this weekend…my nephew Julian stayed with us for the day and came down to the shop.  He’s into trains right now, but we’re working hard to get him hooked on airplanes!

I didn’t take many pictures while assembling the flap housing.  Here’s the forward, and most structural, flap housing brace where the flap motor attaches.  At the top I clamped into place a small, angled splice plate that’s about to be match-drilled to the seat back and brace.  At the bottom, I’ve already riveted two small angles that connect the brace with holes and nutplates on the floor.

The seat floor tunnel cover will need a little tweaking to fit next to the forward brace…nothing that can’t be handled by judicious application of a mill file and scotchbrite pad.

Here’s the back part of the flap housing.  Nothing too sexy here, just a c-channel and piece of angle match-drilled to the rear tunnel cover.  The top is match-drilled to the seat back.  The only slightly tricky part is centering the channel on the seat back; I measured the distance between the prepunched seat back holes, and used that measurement to lay out a couple of reference lines on the channel so they’d be visible through the seat back holes.

Here’s everything all match-drilled and clecoed together.  The side panels are very thin and don’t snug down very well on the forward housing.  I’ll brain out a fix for that later.

Small victories…gotta take ’em where I can. After a lot of head-scratching and experimentation, I managed to fabricate the fuel line that connects the selector valve and filter/pump assembly.

I had a lot of help from fellow builder Bruce Swayze who shared a lot of information on how to bend this fuel line in just the right way. Thanks, Bruce!

Our seats arrived today from Luke and the folks at Classic Aero Designs…they’re very nice, well worth the investment. My good friend Jim has the same seat model in his RV-7 and one ride in his airplane was enough to convince me that these are the ones we wanted.

I’ve been holding my breath on the choice of interior colors, seat leather, and shoulder harnesses. We made our choices two years ago based on leather swatches from Classic Aero, harness material samples from Hooker, and paint chips from Sherwin Williams.  It all looked good in small scale, but there’s no way to tell until everything comes together in the cockpit.

Now that the seats are next to the walls and floor panels we’ve painted with JetFlex, I think we made the right choice…or to be more accurate, Ellen made the right choice.  She did all the color coordination and everything looks great!

Another picture? Sure, why not…

The only downside is that now we know the interior paint color is correct, I’ve got to buy more of it at $120/quart…yikes.

Some days you spend a lot of time in the shop and don’t get much done…a lot of lateral or backward motion, without a lot of forward progress. The last few days were like that.

I mentioned in the last couple of posts that I needed to fabricate an aluminum line that connects the fuel selector to the fuel filter/pump.  Turns out that Van’s ships its RV-7 fuselage kits with 8 feet of 3/8″ diameter aluminum tubing for fabricating all the fuse fuel plumbing, and I used just about all of that trying – and failing – to make one simple damn 8-inch line.

You might think from the picture above that I got it just about right, but there’s just not enough space left at the top of the line to attach the same AN coupling that’s on the other end. So I did what any good civil servant does – I threw money at the problem. I ordered some right-angle AN fluid fittings from Aircraft Spruce that I hope will solve the problem. More to follow…

The next item on my punch list was fitting the forward fuel line covers. Before I could do that some clean-up work was necessary – mounting and torquing a couple of corner gussets that take the place of landing gear weldments for the RV-7A main gear.

Sorry, this is a crappy pic but you get the idea. I’d actually finished these gussets several months ago, but the left one (pictured here) needed some work with a file to clear one of the skin-to-spar rivets. Once the gussets were in place, I moved on to mounting the forward tunnel covers.

The covers themselves are easy, but support angles on each cover’s outboard end require some sheet metal gymnastics to fit and drill to the heavy F-7101 gussets on each side of the fuse. Fortunately, I used a technique devised by fellow RV builder Mike Bullock, and it worked like a champ. I won’t steal Mike’s glory, so here are the highlights.

Here’s a piece of scrap angle clamped in place through the fuel line access hole, to provide a fore/aft reference for the actual support angle. It’s adjusted so it’s flat against the cover.

Here’s the support angle itself, already trimmed and pre-drilled according to plans, clamped to the scrap angle with a piece of 0.020″ scrap in between to simulate the forward cover.

With the support angles clamped in place, I match-drilled them to the F-7101 gussets with a #40 drill bit, which will eventually be upsized to #30.  I used a drill stop to avoid drilling through the outside skins.

Here are the covers match-drilled to the support angles; when they’re done the covers will be attached to the angles with #8 screws. All that’s left is to enlarge the holes to final size and debur everything. It took several hours to fit and drill these parts, but everything came out fine.

Thanks for the great instructions, Mike!

Ellen and I spent the weekend getting our daughter reinstalled in college. After a record-setting (for us) 5.8 hour drive back from Delaware to Boston, we’re both feeling flashbacks of empty-nest syndrome.

Before we left, I made the basic fuel selector/filter/pump housing structure including the fuel selector mounting plate.

This afternoon I fitted the selector, including installing nutplates on the selector for the #10-32 screws that attach it to the plate and selector fascia. NAS1097AD3 reduced-head rivets made the job easy.

Here’s the selector valve and plate temporarily attached to the forward seat floor structure, with the filter and pump laid out on the tunnel cover. Tomorrow I’ll fabricate the “?” shaped fuel line that connects the selector to the filter, and will then check to make sure that there’s enough space for the pump output line to exit and submerge through the cutout I’ve marked in blue on the tunnel.

If everything fits correctly, the pump housing should fit nicely over the whole assembly.

It’s been a little while since my last post, we’ve been busy with family and work. Here’s an update on the fuselage work I’ve done in the last couple of weeks.

Sometimes the most simple things take extra work, like fabricating this simple little tunnel from one piece of sheet metal and two pieces of z-channel. This thing didn’t fit quite as the plans said it should so I had to find some scrap sheet for a replacement…but it’s done.

With the aft tunnel cover finished I started on the heater plenum/forward tunnel cover and fuel valve/fuel pump. Bending the heater plenum louvers didn’t go quite as well as I wanted, but they look mostly ok and no one will ever see them anyway.

I purchased an Andair FS20x7 fuel selector valve, FX375-M fuel filter and PX375-TC fuel pump a couple of years ago and have been looking forward to fitting them. In the pic above everything is clecoed together in anticipation of laying out and drilling the fuel selector and filter/pump mounting holes. The 3/8″ fuel line that connects the two is a bit tricky to bend and I don’t want to lock everything down til I can test fit the whole assembly.

More to follow…

The weather this morning was beautiful, so I rolled the fuselage outside to get some pictures with most of the skins on and the test-painted interior panels in place. All that work on the rolling fuse stand was worth it, by the way.

Looks pretty good, I think…almost like an airplane fuselage!

The interior color looks pretty good…hopefully it’s not too light to cast a lot of reflections on the canopy. Ellen likes it, and I think we’ll stick with it. Our seats are on the way from Luke and the folks at Classic Aero Designs. By the end of the month we’ll be able to sit in the airplane for the first time!

Back from Oshkosh, and the batteries are recharged for more work on the airplane.

One of the goals for this weekend was to paint some of the interior panels with our chosen color.  I splurged on a modestly-priced HVLP spray gun – a DeVilbiss Finish Line FLG-4, which is significantly better than the average Harbor Freight $39.95 chinese knockoff gun.

The weather was perfect for painting, it didn’t take long to get some JetFlex on the baggage compartment bulkhead and two seat floors.  Considering that this was my first attempt at “finish” painting, I think everything turned out well.  JetFlex dries rapidly, and I hung the parts up to dry overnight.

Before I left for Oshkosh, I installed but didn’t rivet the left baggage compartment floor and both rear seat floors.  So the first order of business was breaking out the pneumatic squeezer and pop riveter to rivet the floors in place.  Having done the baggage floor once, it didn’t take long to do it again. The downside? My hands are well and truly tired from using the blind rivet squeezer…but the floors are done.