Installing the wings

Here it is! the BIG one! Installing the wings!! I've been looking forward to this step for a LOOOOONG time!!

I started out by making sure the fuselage was level. The longerons are used as the datum. I had to place a few foam shims under the nose wheel to get it level. This of course is extremely important as the wings must be shimmed to the correct incidence - so if the fuselage isn't level, the incidence would be off!



Checking fuselage level in the roll axis. All good here!


I purchased a bunch of shelves (Home Depot was having a sale) and used them to position the wings into place.


I then used a bunch of scrap foam and cardboard to shim the wings closer into place...


Per the "builders' hints", I used a strap to help hold the wing onto the center section spar. Notice the foam pads on the trailing edge and surface to make sure the strap wouldn't damage the wing.


I tried to align the wing attach center marks the best I could - averaging the outboard position with the inboard position. I then made a pencil mark in the middle of the two sharpie lines (this will be where I will drill the pilot holes later on).



Checking the vertical alignment..



Very happy with the fit...


Both wings temporarily positioned in place...


Foam and cardboard shims did a great job at temporarily holding the wing in place...




Happy with the trial, I then removed the wings to drill the pilot holes on the aft face of the center section spar. I used the pencil marks I had drawn earlier as reference for the buttline. The plans gives the dimensions as to how far down to go. After I had all 6 "x-marks the spot"... I proceeded to drill! No pressure!


Ta-daaaa!!! Pilot holes drilled! Outboard...


Inboard...


I then focused on cleaning up the wing attach pockets...


And then remembered I still needed to drill out the wing attach access holes on the bottom side of the outboard spar. I used a circular saw...


Made sure I was FORWARD of the main spar cap!


Ta-daaaa!!!



I then re-positioned the wings in place. After checking and triple checking (ok, maybe quadruple x 23498234598 checking) the wing incidence, dihedral and sweep, I used bondo to lock the wings in place! Three golf ball size blobs on the top and three on the bottom.


Notice the 2x1 clamped on the inboard end... this helped fine-tune and bring the wing to the correct height.


Super happy with the positioning! Both wings were locked in place exactly where they needed to be! Notice the wing template with the level on top of it - we checked with every top template to make sure the incidence was spot on!


With the wings locked in place, it was time to drill through the forward face of the center section spar, through the pilot holes that were already drilled (on the aft face of the spar) and use them as drill guides to drill through the wing attach hard-points.


After all 6 holes were drilled (3 for each wing), I used a circular saw to open up the holes on the forward face of the spar. I figured it would make it easier to see into the spar as I drilled the 5/8" dia holes later on...



I can see the liiiiiiiight!!!



It was now time to expand the 1/4" dia pilot holes to 5/8" dia holes. This is done with a special "spotface" tool. Aircraft Spruce sells this "kit" for $50+. At the time, ACS was out and gave me a 3 month lead time on one. So I asked fellow builders and Bizman was nice to let me borrow his. Since the bits were worn, I purchased new ones from McMaster Carr

(https://www.mcmaster.com/#3105a21/=1at8aba)



Website said "for woodwork", but they worked great and probably the same ones you get from Aircraft Spruce... and probably why everyone complains on how they wear out so fast...


Any who, I removed the old bit from the shaft.. notice the slots to allow room for the set screws... even with these slots, I still had to grind the head off the set screw a bit to make sure it was below the surface (so it wouldn't scrape the walls of the 5/8" holes!)



Gun loaded... time to rock!!



 Did I say rock? More like panic, hope and pray all goes well...



I've read in 100 places to go slow here... this is to not overheat the aluminum hard points which could then delaminate the fiberglass around it. I tested the bit on a scrap piece on the bench first, and noted I could drill for 15 seconds on slow speed and still be cool to the touch.

So my plan was as follows:
1. Drill for 15 seconds
2. Dip the bit in a cup of room-temp water to clear the metal shavings and cool the bit
3. Switch to another hole
4. Repeat this cycle over and over again until I make it through. Every 10 minutes, I would swap batteries on my cordless drill, and spray room temp water into the holes to help keep them cool.

After 15 seconds of drilling, I would pull the drill bit out...


Dip it into a cup of room-temp water to clear the shavings and help cool the bit...


Every 10 minutes, I would spray water into the hole to help keep it cool and clear of metal shavings..



 Ah yes, the famous aluminum washers! Every time I would feel like I was making zero progress, I would get one of these and rejoice!!


After hours of this process... I finally broke through!!! What a feeling!!! But Ary, how many hours did it take? Do you really want to know? Are you sure you can handle it? Ok, I'll tell you - 13 hours total!! (13 hours spanned over 4 days!!) Slow and steady wins the race, right?



Metal shavings in the pockets...


Pics of the process...





At the end of each day, I drained the water from the cup I used to dip the drill bit in.. this was the metal shavings leftover...


With all six 5/8" dia holes drilled out, it was time to remove the bondo blobs... used a hack saw to release the wings off...


Then scraped as much of the bondo off...


And sanded the remaining bondo off!! Here is Austin (a very talented USF mechanical engineering student helping me with the process)


Time to install the bushings in place...


First, they have to be trimmed to proper lengths.. the inboard ones are easy, since I can see how much needed to be trimmed...


Drew a pencil mark...


Ok, great, but how to trim them?!


So I MacGyver'ed a special tool.. I took a 2x1 and drilled a 5/8" dia hole on the side...


This allowed me to slip the bushing on, and cut it using my bandsaw... notice the aluminum spacer I used to allow an offset so the bushing would not come in contact with the guide...




Ta-daaaaa!!



Measuring the outboard bushings was more of a pain... since you cannot see the backside of the bushing, a special tool is needed..


Place special high-tech tool in place, draw a tick mark on it..


And presto! Depth gauge measured!


Used calipers to measure the tick mark and then transcribed it onto the bushing...


More cutting..





12 bushing cuts later... (6 per wing!)



The bandsaw gave me a rough cut... I then used a metal file to fine-trim to the nearest thou... taped the metal file to the bench and moved the bushing back and forth made it pretty easy...


Ok, all bushings trimmed to size, it was time to bolt some wings on! Moment of truth! No pressure!


I should note that I purchased longer bolts than needed.. this would allow me to shim with washers and figure out how much shimming I was going to need.


I presented all bolts in.. and brought the wing over into position...


A little bit closer now.. a little bit closer...


Houston, we have dock! I then played with adding/removing washers until the incidence was exactly where it needed to be. This took a little bit of patience as it required bolting and unbolting - but finally got it right. The pics below do not show the final configuration - as there are extra washers in there to make up for the longer bolts - I will later replace them with the correct size bolts and less shimming washers.


A shot from the inboard rib...



Look ma!! No hands!!!! The wings are attached and nothing is holding them underneath!! Magic!!





 This was a VERY special day and almost brought tears to my eyes!!!






Wings are officially bolted in place and ready for winglets!!!


2 comments:

vondeliusc said...

Great comment string, especially since I watched the YT video first. The video was a great time lapse. A lot of work, but it is well worth it. My Varieze took the builder (not me) 17 years to build. I have re-done my MLG mounts which took a couple months. You should be proud of your excellent build!
-Christian
VE N191AL S27

Javier Lopez Nieto said...

Grieta Ary