Wing Rear Spars

I'm way late getting this section published.  Wanted to get a picture of the kids with them and kept forgetting, oh well.

There are two parts here that are a little tricky.  Getting the holes created in the rear spar doublers and incorporating the Service Bulletin into the build.

For the holes in the rear spar, I first tried drilling large holes then filing out the remainder.  Pretty sure this is how the instructions tell you to do it.

That seemed to be more work than it was worth.  So instead i drilled the perimeter with smaller holes.

 

Same result, just easier to do.  Once the middle was cut out, I used a half-round bastard file I've had laying around forever.

 

 Oh and here's a BEEFY stiffener that is warped from the factory from the cutting process.  I stuck in in the vice, put tension on it and whacked it a bunch with a soft-faced hammer to get it straight.

 

The service bulletin has been out for quite a while by now, but the instructions still say to do it the old way.  They just give you some parts and a set of instructions for fixing an already assembled wing.  Its fairly straightforward, but does require a bit of thinking.  The new aileron hinge design is SUPER strong.  Here's what it looks like when complete.

 

Next up, wing skins!

Wing ribs

Wing ribs are done.  Took a couple months because of the usual excuse (house remodel).  Unfortunately I didn't get many pics.  This chapter was pretty much dominated time-wise by deburring and figuring out where I wanted to run the AoA/Pitot plumbing, power wires, and coax for a Nav antenna.

Here's a stack of 15 ribs, that's enough for 1 wing.



Early on in this chapter I made one of my few mistakes so far.  You have to cut the aft flange off the most outboard ribs, but leave just a little bit of the radius that transitions from the web of the rib to the flange.  Well I tried it with my bandsaw and butchered the hell outta it.  Ordered a new one from Vans and tried the second time with a cutoff wheel on my die grinder.  Worked much better the second time.

Here's looking at a rib attached to the main spar.  Most of them are riveted in the middle, with a AN3 bolt on the outside.  A couple of the outboard ribs don't have the bolt, just rivets.



Here's the mount for the pitot heat controller I put in.  Just some nutplates on one of the ribs close to where I'll put the pitot.  Notice the big hole there too.  That's drilled to 3/4" so a plastic conduit will run thru for wires.



This shows some little wire clips I bought.  I will use these for the Nav antenna coax so it stays separate from the power wires.  Didn't really need them in both wings, but figured it was easy now, extremely little weight penalty and leaves me with more options down the road.


Two last things.  First, priming these was a big job.  My dad and I spent 8 hours scotchbriting them then spraying.  Marathon day.

Also, for AoA/Pitot I used the left wing tooling hole for one tube, but bored another one on the other side of the rib for the other.  I asked Vans if this was ok, they said yup.  Also the plastic bushings they give you (SB437-4) are not the ones you want to use.  They fit the plumbing tube just fine, but the outside diameter requires you to drill an unnecessarily large 7/16" hole.  I found SB375-4 ones on aircraft spruce that only need a 3/8 hole but still fit the tubing just fine

Wing Spars

Identifying left/right and top/bottom is important on these.  I marked on tape to make it hard to mess up.



As if those huge spars didn't seem long enough, the first thing you do is make them longer.  Match drill four doublers for each spar into the spar extension:



Clamp some J-Channel to the spar flanges and drill a bunch of holes into it.  You don't end up attaching the J-Channel to the spars, this step is just to use the spar as a drill template.  Pay VERY close attention to the plans when they tell you which holes to skip.  The pattern changes a few holes away from the access hole nutplates.  Figure out which holes they are talking about and tape them off.





I skipped around this chapter a bit to get all the pieces that need priming done at once.  The extruded pieces are the wing tiedown points.  They get drilled and tapped to accept eye bolts then match-drilled to the spars.



Here is the spar extension riveted.  First wing rivets!  Building juice optional:



The majority of the work on this chapter is in countersinking all those spar flange holes.  There's a ton of them!



For the nutplate countersinks, the plans specify a maximum size for the top and bottom of the countersunk hole.  I'd say an accurate measurement is mandatory here.  On the tank attach nutplates, my skins weren't quite flush with the spar flange, but it was real close.  Research showed this was OK.


The wing tiedown blocks riveted and bolted:



Aileron actuation brackets on the back side

Wing Day

The wings are here!  Van's estimates 8 weeks for wings arrival, and these took the full 8 weeks.  Even with that full wait time, they still didn't send the fuselage spar carrythrough.  Its not needed for the wings but they send it anyway for some reason.  It showed up in its own box about a month later.

The spar box is LONG - about 12'8".  Here's my truck after picking it up at the ABF trucking terminal.




Here they are with the top of the crates popped off



They wrap everything in crazy amounts of packing paper. 



Here's the hardware bag.  Holy motherload of rivets!! 



Time to get to work