Kit Airplane: Wing Part 6 (Wingtips)

The aircraft has specially formed fiberglass wingtips. They fit... questionably...

And the bottom...

And the rear...

Starting from the front, I shifted the fiberglass wingtip as best I could for each hole as I drilled to the back alternating between top and bottom.

The tricky part was getting sufficient clearance between the holes and the edge of the fiberglass.

It came out pretty well in the end. I'll likely add some fiberglass material to some portions of the bottom to increase the distance from the edge and the rivet holes.

Kit Airplane: Wing Part 5 (Leading Edge)

And now on to the most nerve-racking part of the construction so far (possibly for the whole build) - drilling the leading edges onto the wings. The 12' long wings must have their spars at 81 degrees, level between the front spar and rear channel, all the ribs lined up with the predrilled holes of the skin, the leading edge skin centered over the nose ribs, held in tight to conform to the shape of the ribs, and drilled into the flanges of the spar. There is no undo; it has to fit. And significant mistakes have cascading detrimental effects on every part of the wing made so far. If it's bad's enough, I can't use any of the wing.

Marks were made on the ribs and skins to verify alignment...

Marking the leading tip of each of the nose ribs...

Using a piece of paper with marked distances to find the center of the skin... 

Drawing a line down the center...

The leading skin edge has predrilled holes for every nose rib except for the one for the fuel tank as there are 2 different tank sizes available. I needed to measure its location offset from adjacent ribs and then mark down where to add pilot holes.

The leading edge bottom clamped (and taped) into place. I use the predrilled holes (and the pilot holes I added for the fuel tank rib) to line up the ribs underneath the skin.

There is a line drawn along the edge of the leading edge skin to position it along the spar and lines drawn on every rib. I need to ensure those lines are visible through the predrilled holes in the wing skins and the leading edge skin.

And drill down the shape of the leading edge...

After all of the holes have been drilled (including along the spar), I flip over the wing to get the top side complete..

And here was the stressful part. The skin is a fixed precut size. It must reach around the ribs and underneath the skin on the top side of the airplane (with its predrilled holes). Those wing skin predrilled holes go through the flanges of the wing spar. This can't be misaligned.

I used ratchet straps to pull over the wing skin, and I was so relieved to see my marking line through the predrilled holes of the skin. That means I'm able to successfully drill through the wing skin, through the leading edge skin, and though the spar.

I used a strip of wood to apply pressure through the span as I was drilling...

Going down through the shape of the airfoil...

Once all the holes were drilled with a #40 bit, I flipped the leading edge skin to be at the top / above the rear skin. 

Then went through all the holes and drilled to final size...

The same process was repeated for the other wing. The bottom...

And drilling the top... Again I was thankfully able to line up the edge marking through the predrilled holes.

Continuing to drill the top side with the #40 bit...

Then I flipped the leading edge skin to be on top again and drilled to final size...

Kit Airplane: Wing Part 4 (Pitot Tube & Tie Down)

The underside of the left wing needed the pitot tube to be mounted.

Holding up roughly where the pitot tube will go. Alongside one of the ribs (half of its rivets will also go through a wing rib). I needed to drill a couple holes for the tubes.

Tube holes drilled then filed larger for size.

I marked and predrilled corner holes of the pitot tube mounting base. Next, drew a line between the rib's holes to determine the lateral position. The placement longitudinally is based on the distance from the spar.

Pitot Tube attached!

Alignment looks great with the wing!

The tie down was also drilled for the wing...

It's also along one of the wing ribs; the wing's rib has predrilled holes on its side that align with the tie down's holes. There is an existing slot it pokes out of, but I had to file it larger to get the tie down positioned correctly.

And inside the wing, the tie down clecoed in place.

The holes drilled to final size inside the wing...

And the holes drilled to final size on the outside of the wing...

Kit Airplane: Wing Part 3 (Rear Channel)

Been a long time since my last airplane kit update, but a lot has been done. For this update I'll go over the rear channels which have been completed on both wings.

Laying out all the pieces...

Began assembling them...

Clamping the root to be able to drill doublers...

Drilling the parts...

And prepping the reinforcing L-angle...

Drilling continued...

All drilled...

How the center section looks where the two rear channel pieces are held together...

Kit Airplane: Wing Part 2

 Continuing the wing, here are the left and right spars laid out.

And lots of rear ribs to attach to them...

Going one by one down the spar clamping, drilling, and clecoing.

Continuing on...

Rear ribs attached on both wings!

Then it was time to move on to the nose ribs...

Getting the nose ribs aligned involved multiple overlapping strips of aluminum above and below the spar (to mimic the wing skins) and clamps of the ribs against the L-angles.

There is a spacer in the rib below to ensure the rib is offset from the spar an equal amount the entire length of the wing. The inner most ribs even had to be shaved down to compensate for the thickening spar.

Once it's all aligned though, can start drilling and clecoing in place.

The innermost portion of the wings has an additional reinforcement that is bolted on. That aluminum plate has to be removed to attach the ribs.

Each rib required slightly different drilling methods as it's quite close quarters against the spar and their attachments all varied.

All ribs on the left wing complete!