Wings: Bottom skins. Right outboard skin on.

The right outboard bottom skin is on the wing for good.  Both bottom skins on the right wing were riveted solo.  Generally, this wing went much faster than the left side as that previous experience (literally) carried over.  Instead of placing one rivet-at-time, I would tape in a rivet per rib then bang them in across the wing, moving down to the next row (columns would be ribs).  For the J-stiffener and spar flange, I went outboard-to-inboard 5-to-6 rivets at-a-time, each bolus taped in.  Made things much faster.

Below is when the aft half was complete.  The blanket in the background was for my poor, poor knees.

I had some consistent trouble along the 11th rib on the forward half.  The bucking bar slipped off the rivet at four consecutive locations, giving the skin a good bit of...character.  Otherwise, there are far fewer dents than on the left and only two Rivets of Shame were needed.  And no oil-canning as I was fastidious about the riveting order.  A different outcome than the left side.

 

This also marks the end of use of AN426AD3-3.5 rivets for the wings.  In fact, this marks the end of all bucked rivets for this kit, given where I'm at.  This bottle, back in April, was nearly full!

Wings: Bottom skins. Right inboard skin on.

A mere status update:  I got the inboard bottom skin on the right wing myself.  Took only 4 hours, unlike the 9 it took for the analogous left side.  My work on the right side is much better than the left.  In fact, generally, the right wing is better than the left.  Guess that means I'll need to trim out some adverse yaw!

The towels were to catch the bucking bar if I dropped it, as I did once before.  And they did their job, twice, thus saving the spar.

Wings: Bottom skins. Left outboard skin on.

Left outboard skin on.  Was very difficult to contort and reach the rivets with the bucking bar.  I ended up with two Rivets of Shame (should have just left them alone).  Only the backing plate for the heated AOA/pitot remains to be riveted.

One very disappointing outcome was two sectors (that is, skin bounded by rivet lines) oilcan pretty badly (between the 10th-11th and 11th-12th ribs, forward sides).  One pops in and out with little applied pressure.  It's probably related to the very tight fit the ribs had on those sectors.  In fact, in a few isolated places, the rib flanges don't sit flush as the rivet carried the flanges away from the skin.  Options to fix include drilling out the rivets on those ribs to achieve a better fit (which risks messing up the holes, of course), or sliding some J-stiffener in there to prevent the skin from flexing.  Turns out, I have a lot of extra J-stiffener, so that may be what I ultimately do.

Here I am riveting the outboard flap bracket with a 5.5" long straight flush rivet set.

You can see the oil canning rather prominently in the image below.

Wings: Bottom skins. Left inboard bottom skin on.

I managed to rivet on the left inboard bottom skin by myself.  Nine hours!  I had a few very minor dents in the skin as it's extremely difficult to manage this task alone.  Also put a bit of a dent around the flap bracket mount and ended up with a Rivet of Shame there.  It's dangerous to use a mushroom set and a back rivet set in this area.  I've since ordered a narrower and longer flush set to work with the remaining flap brackets.

The plans say to cleco the bottom skin from the rear spar to the J-stiffener, then carefully lift the skin to access the underside for bucking.  Well, that's just not possible frankly.  Or at least, I couldn't manage it without kinking the skin.  So I cleco'd each row progressively as I went and ultimately forwent riveting from the center out and forward.  I was fastidious about that approach with the top skins and outboard leading edges but it wasn't an option here.  I noticed no "oil-canning" of the skin.

During this process, I recalled how my friend with an RV-9A had dropped his bucking bar when putting in his bottom skins.  He put a nice dent in the top skins that is quite unsightly.  I desperately wanted to avoid something similar.  However, I indeed dropped my bucking bar once.  Since I riveted with the wings in the position shown in the images, the bar fell (corner down, no less) into the main spar, bounced twice and ended up two ribs outboard from the drop point!  My butterfingers caused two very nice gouges in the spar which took 45 minutes to carefully sand out.  Ugh.  I'll need to clean and spot prime these areas as the alodine is gone now.

Subsequent riveting of the bottom skins will see a nice thick towel adorning the spar to accommodate any falling objects.

Accessing the rivets under (fore) the J-stiffener is a challenge.  I used the left bar on those guys.  Elsewhere I used the right bar and my tungsten friend in the center.  The gun was calibrated so that two short half second blips fully set a rivet.

An MS21053-L08 single leg nutplate is called out on the aft inboard bottom skin.  The plans previously had the skin/rib rivet holes for this part dimpled.  However, this steel nutplate has its rivet holes undimpled.  I tried to dimple them but the part just warped rather than taking on a good dimple.  After several attempts to rectify, I gave up, pressed out the skin/rib dimples and countersunk the skin holes.  All good.  This advice was give to me by Sterling at Van's.  He's always so helpful and thorough.

Left inboard bottom skin locked down for good.

And here is the left bottom skin ready for riveting.  I'll try going at it myself once I get my narrower and longer flush set, but I bet I forgo the attempt in favor or some help.

Now it's time to let my hands and arms heal from all that close-quarters trauma.

Wings: Bottom skins. ADAHRS mount.

I have to redo the ADAHRS mount.  Looks like the mount slipped when I was match drilling to the J-stiffener, so it didn't fit properly after I riveted the whole thing together.  This caused the J-stiffener to bow a bit.  Bummer.  Interestingly, the tray shipping from Van's is now sans tab.  See the first ADAHRS post to read about that tab.

Original ADAHRS mount on top.  New on bottom.

Wings: Bottom skins. Flap gap stiffener reversal.

The plans clearly call out the W-1021B Flap Gap Stiffener to keep its flange outboard.  On the left wing, I put it inboard since that made the most sense (to me, anyway).  So when I went to do the right I took a quick gander at the plans to refamiliarize and realized I reversed it on the left, but not before the whole flap gap fairing was riveted in.  So fixing that would be quite challenging. 

Sterling at Van's graciously went to look at their flying -14A (N214VA) and their bird is actually opposite of plans.  He said either orientation is fine so I'm going to leave it as-is.  My concern was clearance issues against the fuselage rather than drag. 

 

Wings: Pitot-static. Pitot hole made.

Here's a series of images capturing the fashioning of the pitot hole in the left bottom skin between ribs 8 and 9, butted up against 8.  A few pilot holes were drilled, followed by enlargement by the unibit, removal of skin with the nibbler, filing to get a good fit and final deburring with 400-grit.  An hour and fifteen minutes of after-dinner work.

 

 

 

Read the entries in my AOA series:

• Parts.
• Mounting - 1, 2, 3, 4, 5, 6 & 7.

Wings: Bottom skins. Prepping skins and priming gap fairings.

The bottom skins are in the works as I wait out tank completion and figure the logistics for moving the wings as-are out of the basement.  I can't let the wings get bigger lest they need to be removed by lifting the carpet and floorboard from between two joists to push the wings out.  Right now they will fit through the egress window, which is the best option (indeed on 18-Aug-13, that's how it was done).

First I cut the vinyl from the rivet lines, then match drilled the inboard rib to the nutplate holes for each wing.  This was the first time I've used the clecos all gunked up with sealant.  I'm not a fan.  I'll be looking at cleaning them...somehow.

In looking at the plans, I can put on the flap and aileron gap fairings (Section 20) prior to systems wiring (Section 19).  This lets me get ahead as I wait out attaching the tanks and leading edges.  So, I've primed the farings plus the ADHARS mount and J-stiffeners.  Here are those parts lined up for priming after cleaning and etching with Stuart System's EkoClean and EkoEtch.  The tanks are front-and-center awaiting more work.

Here are the parts all primed with EkoPoxy/EkoPrime.  You can see an outboard bottom skin with the rivet lines exposed in the foreground plus the tank rear baffle and attach zees in the background.

Wings: Bottom skins. ADAHRS mount.

The W-00012A ADAHRS Mounting Plate has a tab on it.  It does not appear in the plans.  The tab impedes good alignment with the J-stiffener.  Ken at Van's says the tab is there to keep the bracket in the right place for drilling and can be removed.  I removed it before drilling since the alignment wasn't good with it.  He also confirmed that the bracket is to hold a Dynon ADAHRS.

 

Here's how it worked out, following match drilling of the #30 holes to the J-stiffener.