Wings: Aileron actuation. Complete.

Aileron actuation is complete.  The rigging took me 11 hours.  Most of that was consumed in using the wrenches in the severely restricted space within the wings.

First, one of the threads on my pushrod threaded rod end was damaged. Don't know if it came like that from the kit or if the weld shop did that (probably the latter, as it looks like drop damage).  Fearing $100 to fix (new rod and welding labor), I learned I could use a rethreading die to solve my woes.  This is part of the "education" mandate in experimental aircraft construction.  I.e., I did not know one could fix damaged threads.  Below is the 1/4" 28 TPI die itself and in action.  I used a little oil to help it cut, along with a progression of two twists forward and one or so back to remove the debris.

Left side is damaged thread, right side is fixed.  The thread was bad enough to strip the AN316-4R jam nut.  I had to replace it.

The plans call for a 1 1/64" spacer to be used to clock the torque tube subassemblies. 

That's some mighty fine resolution in measurement.  I whipped out my compound miter saw to cut a piece of wood down to about 1 1/8" then worked it down with a long, flat file using my caliper to measure.  Once that was done, it's just a matter of engaging the torque tube collar to the right length (I went for 17 3/4") then completing the requisite match drilling.  Left and right shown on their respective sides below.

I foolishly torqued in the final bolts before approaching the wing roots.  Realizing I skipped a step, I eviscerated some time removing a few bolts.  Curious why my collars are primed grey and not the usual white as seen elsewhere in my build?  Read here.

Installation of the subassemblies must be completed with little to no pre-loading on the flanged bearings.  On each side, I had to use three NAS1149F0432 washers (two on top, one on bottom) to properly seat the subassemblies. Left and right shown on their respective sides below, top to bottom.  The washers are clearly visible.

Here they are, torqued down awaiting Torque Seal and the next pushrod.

The plans call for a NAS1149F0363P washer to be inside the torque tube clevis arm along with the pushrod bearing.  This is not easy as the arm must be spread to fit the bearing and washer.  I wonder why Van's called for this.  Left on left, right on right.

 

Here's the bellcrank jig to hold the assembly in the neutral position.  This is to properly size (by engagement of the rod end bearings) the torque tube to bellcrank pushrod.

Aileron pushrod installed onto aileron.

The alignment template holds the aileron in the neutral position.  Notice how the aileron is actually deflected slightly upwards.  This is apparently by design. 

Everyone's torqued down onto the left bellcrank.

The torque tube gets very close to the main spar web in the full up position.  That might require sanding out later (Update 15-May-18:  It didn't).  The hole that's shaped in the kit seems to be too large inboard and too small outboard.  It almost as if the hole should be translated outboard in the master plans.

Wing tips next.  I marvel at the folks who bang out wing kits in 300 hours.  I'm on track for 600+ (Update 15-May-18:  It took 611 total)!  On 21-Jul-13 I guessed 450 hours when the tank baffles were ready for countersking.  On 5-Oct-13 I guessed 700 hours when the flap skins were being bucked.

Wings: Right aileron mounted.

And now the right aileron is mounted.  Those MS21042-3 locknuts provide some serious friction!

Both wings with their ailerons.  I need to pull the left wing's carpet higher.

Wings: Aileron actuation. Bellcrank to aileron pushrods.

Since the torque tube to bellcrank pushrods are aluminum, they could be primed with my usual Stuart System's EkoPrime (reminder, don't use a water-based primer on steel).  For the interiors, I taped off one end of the tubes and all the rivet holes then poured the primer down the tube.  After rolling it around for a while, it was well coated.  Curing took more than a week given the absence of airflow and puddling on the bottom of the tube (every day I'd rotate it 90 degrees to spread it around a bit and mitigate puddling).  This is a key point since the VA-111 Threaded Rod Ends were previously sanded to fit snugly without primer, so a puddle of dried primer on the interior just makes fitting that much harder.

Here's the VA-111 Threaded Rod end prior to riveting.  I took this picture to match the image in the plans.  I used Napa 7220 on the rod ends since it's thinner and more compliant when sprayed on threads (Stuart's can gum up threads).

Given all the primer in the tube's interior, it wasn't an easy task to get the VA-111 threaded rod end in there.  I had to pound it in against my workbench fairly violently.

It's key that the holes are well aligned prior to the pounding, otherwise you're left with trying to rotate a piece trapped by a lot of friction.  This happened to me on one end so I had to use the approach shown below to rotate the piece.

Here are the completed ends.  The MSP-42 rivet manufactured heads conform to the tubes' curvature - not something I expected to happen.  Rod ends need a quick touch-up of primer before final install.

Wings: Aileron actuation. Bellcrank to aileron pushrod weld.

Turns out that not only is it difficult to drill steel, as I learned with the aileron counterweights, but it's also difficult to drill into steel straight, from one end of a tube to the other.  In fact, I totally botched the first pair of steel pushrods and had to drop some $30 for a replacement tube (ST4130-035X1/2X48-PC).  To make things easier, one ought to use a drill jig (my approach) or use Mike Bullock's miserly approach.  In either case, the jig helps secure the tube in the drill press.

However, after drilling my steel pushrods, I came across the notion of welding the bushings into the pushrods rather than riveting.  This notion is fraught with some interesting discussion with respect to the hardness of the steel following the welding.  It appears to essentially come down to, yes the steel will be weakened, but it will be far stronger than 2 rivets holding each bushing in.  Also, the use of aluminum rivets on steel can promote corrosion due to the dissimilar metals.  Apparently, this approach is not permitted in the certified world.

Ultimately, I decided to have a local shop TIG weld my bushings for fifty bones.  You can see the holes I previously drilled for the rivets.

And I reprimed the areas where the powder coating was removed.  The interiors were primed (not shown) by taping off one and spraying Napa 7220 (reminder, don't use a water-based primer on steel) in the tube and rolling it around until the interior was covered. 

I decided to drive rivets into the bushings anyway, as an extra measure of safety, should the welds break.  Though ideally I would use MS20615-4M11 (which I can't seem to source), the concern of any associated corrosion is fairly minimal given the thousands of kit planes in the air using that approach.  With that in mind, I went with the plans' recommendation of AN470AD4-11.  Not the prettiest shop heads in the world but they'll work fine if the welds break.  I drenched the area with primer to mitigate corrosion.

Wings: Aileron actuation. Priming and flash rust.

Learned a new term on this round:  "Flash rust".  The aileron pushrods and torque tubes are composed of steel.  Most of it is powder coated from the factory, however the tubes' interiors are not.  So they must be primed.  I dutifully used my Stuart System's primer.  The next morning, I went to check how it was drying and found this (view looking inside one of the tubes):

And this:

In fact, every piece rusted where the primer was applied.  Turns out, this is called "flash rust" and is due to the water-based nature of the primer, even though the primer is specified for steel.  As soon as I saw this, I knew I was in for a good solid several hours of work as part of a remedial effort.   How to do that?  A bag of steel wool and a 12 gauge rod of steel clamped down in the vice was mostly the ticket.  I stuffed the steel wool very tightly into the tubes, then worked it back-and-forth until most of the primer and rust were out.  Then I used the rat-tail file, added some acetone with the steel wool once more and finally used a flap wheel on the drill to effectively sand the insides down. 

Eventually, I worked all the primer and rust out after some 5+ hours.  I reprimed with Napa 7220.  Not a water-based primer.  No flash rusting occurred.

So, that was fun.