Monday, April 22, 2013

Section 15, the Leading Edges, Complete

Build Hours Added Since Last Post:  4.5

As I write this update, Section 15 and the final work on the leading edges are now complete.  As you can see from the build hours put into the final portion of Section 15, there wasn't a whole lot left in this section.  It was a simple matter of fitting the landing light lenses in the leading edges of each wing and securing assistance to drive the rivets attaching the top skins of the leading edges to main spars.

Up until this point, all of the work I have done has involved aluminum and metal.  The landing light lenses were my first venture into the tedious and frustrating wonderful world of plastics.  From my basic understanding of what's to come, the RV build does not involve a lot of plastic.  However, there is one large component to the project that has the reputation of being one of the more stressful sessions to completion--i.e. the canopy.  So, I guess it's good that we get a very small taste of whats to come.

The raw landing light lens is first rough trimmed and then covered in a layer of masking tape to protect it from any scratching.

Rough trimmed lens with masking tape.
The lens is then placed in the landing light opening where a line is traced that depicts the opening in relation to the lens.

The mounting brackets are temporarily placed for reference.

My drawing skills are crude, but effective here.
The lens is then trimmed, and holes for the bracket are drilled and countersunk.

It's then time to adhere the brackets to the lens using double-stick tape.

Finally, the lens is mounted to the leading edge using stainless screws.

Interior shot

With the landing light lenses mounted, and the final rivets of the leading edge skins driven into the main spars, it's time for the wings to be safely tucked away while work commences on Section 16 and the fuel tanks.

Friday, April 19, 2013

Section 15 -- Work on the Outboard Leading Edges

Time Added since Last Post:  17.5 Hours

The last time I posted, work had commenced on the outboard leading edges.  Since that post, I have managed to complete most of Section 15.  The one lingering item to complete is the landing light lens.

The leading edge skins receive the same dimpling treatment as the aft skins.  It was a bit of chore to maneuver the curled pieces of aluminum, but once I had the rhythm down, it seemed to go quickly.

For easy access, the instructions directed that the ribs and skin area immediately surrounding the landing lights should be painted.  They recommend black or white.  While it seems that most people building the RV-14 have chosen black (including the demo/prototype model), I thought white would have a cleaner look.

Interior of leading edge painted white.
Landing light lens cover mounts.
Ribs painted and cleco-ed in position.

The left side has an access whole so that one can service the stall warning device.

Left wing access hole.

Here's a shot of the stall warning device from the inside.

Once the accessories were installed, the wing skins' rivets went in with little effort.

Completed leading edge

With the leading edges put together, the next item was to marry them to the main spars.  This was my first opportunity to use my pull (pop) riveter.

Attach points of the leading edge wing ribs are pull riveted.
The left wing claims its first insect casualty.  Hopefully many more to come!

Shockingly, the wing kit does not include any tie down rings.  In fact, the instructions state that the builder should order them from Vans.  While I'm sure that the tie down rings offered by Vans are similar to any other tie-down ring, I opted to order a couple from Cleaveland Aircraft Tool Company.  They offer a powder coated version that looks great.  In the picture above, you can see it installed next to the access hole.

Top of the left wing waiting for rivets.

Monday, April 8, 2013

Section 14 Continues--onto Section 15 (the Leading Edges)

Hours added since last post:  26.5

The last time I checked in, I was in the midst of affixing the top wing skins to the posterior portion of the wings.

Thanks to Renee's help, the top skins are all riveted and tucked away while work has started on the leading edges.

The left wing is riveted.

Yours truly standing next to the right wing.
Per Van's instructions, we back-riveted the top skins.  The standard riveting process involves banging the rivet gun against the rivet head (otherwise referred to as the "factory head") and holding a bucking bar against the other side to create the "factory head."  But, because we have easy access to the inside of the wings, it's much easier to back rivet the rivets by having one person firmly hold the bucking bar against the factory head on the outside of the wing skins while another person fires the rivet gun against the inside to create the shop head.

Flush factory heads.

Shop heads on the inside of the wing.
Ribs, top skins, and J-channel installed.

Outboard aileron bracket riveted in place.

With the top skins all set and tucked away, work begins on the outboard leading edges.  The leading edge of each wing is split between the outboard leading edge and the interior leading edge.  The outboard leading edges house nothing more than the landing lights while the interior leading edges are also the fuel tanks.  The RV-14 uses a "wet wing" fuel system.  A wet wing means that the wing is the fuel tank.  When finished, each tank should hold about 25 gallons.

So, it was back to straightening the leading edge wing ribs and fluting the flanges to align the flange attachment holes.

Wing ribs as supplied.  Note how it does not sit flat on the table.
A fluted wing rib should sit flush on the table.  The flute bends are seen between the flange holes.
Right wing outboard leading edge cleco-ed in place.

Once the leading edges are finished and attached to the main wings, the arduous process on the fuel tanks begins...

Monday, April 1, 2013

Section 13 Finished--onto Section 14

Hours Added Since Last Post:  23.0

Over this past week, I made some very good progress with the wings.  You might recall that from my last post, I was working through the rear spars.  While the rear spars were all but ready to be attached to the wing ribs, I needed to finish one final step--which involved the first official use of my new newly acquired drill press.  The 3/8" undersized reamer I ordered arrived just in time for the weekend and I was able to ream the designated hole on each rear spar with ease.

Rear Spar cleco-ed and ready for rivets.

With Section 13 officially complete, I moved into Section 14--the top wing skins.  Whereas with the first few sections, for this section, I have decided to work both the right and left wings at the same time.

 As with many projects, a lot of time goes into the work no one sees and it seems like it take a long time with no visible results.  That all changes, however, with the placement of the wing skins.  There's also a bit of trepidation given that the top wing skins are visible to all who look.

Inboard top wing skins fitted
Countersinking inboard top wing skin where the wing-walk doublers are located
Since entry and exit to and from the cockpit requires standing on the wings, the inboard most portion of each wing includes a set of doublers under the top wing skins.  Specifically, there are twice as many wing ribs that support extra thick skins thereby supporting the weight of whomever walks in that area.  Accordingly, the skins are countersunk for flush rivets rather than the standard dimpling.  The above photo depicts a countersink while the below picture shows dimpling.

Dimpling takes place upside down in this case--so you are looking at the bottom side of the wing skin.
The C-frame in dimple action.
After everything is dimpled, final drilled, and countersunk, it was time to prime the inside of the skins (not pictured).

Top wing skins placed.

Top wing skins in position and ready for rivets.
Flush rivets are going in!

The top wing skins take two people to rivet.  For the top skins, the instructions suggest that the builder back rivet, which means that instead of riveting on the outside of the skin with a bucking bar on the inside portion of the rivet, the rivet gun is hammered against the inside of the skin and the bucking bar is held flush against the exterior top skin.  When done right, it creates a cleaner look for the top skins.