Sunday, December 28, 2014

Wing rib & rear spar deburring, trim tab assembly, wing main spar countersinking

Didn't get many pictures of this session, but there was a lot of repetitive work happening:
 
I disassembled, deburred & dimpled the trim tab, primed the mating surfaces and installed the first 2 rivets on the trim control brackets.
 
I found while deburring that I had elongated one of the trim tab skin-spar holes, and had to drill it to #30. I know paint will *mostly* hide the fact that there's a larger rivet there, but I kind of like knowing where the warts are. Here's hoping there aren't too many.
 Meanwhile Erin deburred wing ribs (mostly lightening holes), Brian Judge deburred the wing rear spars, and I finished countersinking all of the #8 screw holes in the top of the right wing main spar.
 
Empennage: 3 hrs
 
Wings: 4 hrs


Sunday, December 14, 2014

Trim tab drilled, Tank skin nutplates riveted

We got a couple short sessions in the shop working on the trim tab prep & wing spar nutplate riveting.
Everyone who builds a plane should have someone with tiny fingers to place rivets!
Meanwhile I aligned the trim tab hinge per the specs and confirmed it by aligning the tab with the trim tab cutout in the left elevator.
Trim tab match-drilled! Ready for disassembly, deburring, etc.
We continued riveting the nutplates to the wing spars on Sunday with Brian Judge's help. I have a few to buck where we don't have clearance for the squeezer around the 3/16" wing spar rivets and will post pics then.
 
Funny side note: Christmas cookie baking was happening inside, and Nat was clearly impatient to get out to the garge - she didn't like that I was working out there without her. I hope we can keep up that enthusiasm with everyone for a long time!
 
Empennage: 1 hr
 
Wings: 2 hrs

Saturday, November 29, 2014

Left elevator riveting, trim tab bending, wing tank platenut assembly

While Dad & Ben started riveting the left elevator skeleton I finished the trim tab bends and clecoed on the rear trim tab spar.
These bends were a piece of cake compared to the tabs on the LE.
The guys did a great job riveting on the platenuts and reinforcement plates.
Likewise the counterbalance ribs were riveted together quickly.
I clecoed and clamped the trim cable attachment horns to the bottom of the trim tab and match drilled them to the skin.
I then removed the horns and marked them for cutting, and then set aside the trim tab to help with the left elevator assembly.
 
These flush head rivets seemed to go a bit easier than on the right elevator, but there still isn't much room to get normal (90 degrees) to the forward side of the spar. And bending the root rib isn't an option, since it just creates a gap that the rivet would fill.
Next up: elevator control horn installation. Dad provided expert supervision.
Squeezing rivets - the method acting way:
We were prepared this time and dabbed the RTV on the stiffener ends BEFORE riveting the skin to the skeleton. Even low slearners can be taught...
 
When riveting the narrow end of the counterbalance rib on the right elevator we had an interference problem with even my no-hole squeezer yoke - on the top, of course - and had to use a combination of the rivet gun & mushroom set with a flat head screw driver and thin polished bar steel, finished off with a shot from the no-hole squeezer. It worked, but it wasn't easy or pretty.
We planned ahead on the left elevator, riveting the top first and changing the pattern, and were able to set all rivets with the no-hole yoke. MUCH easier!
We had a lot of help riveting the skin to the skeleton. Dad, Mom, Ben, Sam, Erin & I each got to squeeze a few rivets. It was great to see everyone excited to help!
 
 
And then everyone got to sign the finished part!
 
We closed up the bottom skin but left the top open near the trim tab (inboard) area to allow easy access when mounting the trim hardware.
Setting the elevator aside for me to finish the trim tab assembly later, we brought out the wing spars which I had countersunk for the platenuts, and primed the countersunk holes.
Next up we had a 3-man operation clecoing platenuts to the spars, riveting them on, and...I'm sure I was doing something important, too.
1/2 of a spar done!
I had to drill out about 8 rivets and am sadly getting pretty good at it...lots of practice I guess. I mangled a few nutplates in the process and will have to order more.
Mom proved that whacking my brothers & I with wooden spoons when we misbehaved was good training for squeezing clecos.
These were the best build sessions I've had so far, and are exactly why we started this project: spending time with people we care about, everyone pitching in & learning along the way.
 

Empennage: 5 hrs
 
Wings: 2 hrs

Friday, November 28, 2014

Right elevator complete, wing main ribs straightened

Friday we guys snuck out to the garage after the ladies returned from propping up the local economy.
First we finished deburring & riveting the rolled leading edge of the right elevator.
Dad worked at the grinder on a couple 6" scraps of flat bar steel & 3/8" bar steel that I acquired for use as bucking bars. They need a little polishing, but we've already tried out one and it'll be a nice addition to the toolbox.
Meanwhile our lovely assistants helped strip the vinyl off of the right elevator and inspected our work.
 

Another finished part!! I also brought in the rib flange straightener and Dad worked on the wing main ribs while the rest of us were yakking after dinner.
 
Empennage: 2 hrs
 
Wings: 1 hr

Thursday, November 27, 2014

Right elevator assembly, elevator trim tab progress

We flew in a bunch of help for the Thanksgiving weekend; first Natalie had to train the new recruits.
 After Uncle Benny passed her inspection (clecoing, drilling deburring, riveting on practice material), he set to work riveting the right elevator counterbalance skeleton together. He really leaned into it.
The flange-nosed yoke I bought was essential here, as I only had 1 flat die that was long enough.
 Next he & Dad riveted on the spar reinforcement plates and nutplates for the control bushings.
 With those on we installed the root rib with flush head rivets; these were a bit tricky to get to but all 4 rivets turned out pretty well.

Our lead helper came back to check on us & attach the right elevator horn.
Skeleton complete!
Per the suggestion of the Van's instructions we installed these two rivets to avoid having to install blind rivets later.
 That done, the skeleton slid in easily, the counterweight fit nicely and we proceeded to rivet the skin to the skeleton. 
 After finishing the bottom skin I remembered that we hadn't applied the black RTV at the intersection of the stiffeners inside the skin; access was tight, so we made a bit of a mess, but we got it in just the same.
 While the guys set some of the skin rivets and prepared to roll the leading edge I worked on bending the left elevator trim tab tabs.
 These were easier to bend than the tabs on the elevator itself, mostly because I used more double-sided tape and was able to clamp them more securely.
 We headed in to carve the turkey with a nearly complete elevator! We got the leading edge rolled, match-drilled and ready for deburring. Man, these things go together fast with lots of help.
 Dad picked up right where he'd left off after helping start the horizontal stabilizer last fall, and Ben picked it up quick. It's just a shame we're a thousand miles apart!
 
Empennage: 5 hrs

Monday, November 10, 2014

Left elevator tab bending, wing tank skin platenut drilling & deburring

I decided to tackle bending the tabs on the left elevator skin and trim tab. Rumor has it this is and the trim tab are the most common areas for mistakes on the empennage.
I stripped the vinyl from the tab area and marked a line perpendicular to the trim tab cutout. Then I fabricated some bending blocks at an 11 degree angle based on a survey of other builders' sites and a check with my protractor of the elevator finished angle.
The blocks were taped into place with double-sided tape. The pictures in the manual describe clamping it to the table, but they only show this for the trim tab, and I couldn't find an effective way to clamp the blocks while leaving myself enough room to work. Instead I clamped the elevator and the rear spar on both ends and hand-clamped the blocks while I worked first the bottom tab, then the top.
My lines must have been slightly too far inboard of the ideal, because I had to file the edge of the bottom tab to get it to clear the upper tab (in the photos, the bottom side is up).
Other than the filing, with some patience, a block of wood, and finishing the tab with the rivet gun & mushroom head set at 10 psi, the bottom tab moved into place.
 
The upper tab seemed to go smoothly as well until I hit it with the rivet gun. The block must have moved out of place, causing the radius of the bed to go from 1/8" (per spec) to about 1/64" (too small).
This could be a problem as radii less than 1/8" can lead to cracking at the bend.

I'll send the photo in to Vans and see if I need to remove the tab and fabricate a replacement, or if it's acceptable and just bears close inspection to ensure cracks don't form.

Aside from that minor setback, the tab bending was easier than I expected. I set the elevator aside and with help from Brian Judge pulled out the wing spars to mark orientation.
We noticed a spot near the etched serial numbers that looked like corrosion; it appears that the riveter may have skipped off the surface. I removed the corrosion with scotchbrite, and will clean & prime this later.
We drilled out the #40 holes for the tank skin platenuts, Brian deburred on the inside of the spars while I worked with the countersink on the outsides.
And then with the help of this lovely assistant we squeezed the first rivets on the wings!
Brian got to try his hand using the squeezer - his first rivets on the plane.
While I continued chewing aluminum with the countersink, Brian started edge-deburring the right rear spar.
We made great progress, and are officially started on the wings!! And almost exactly one year to the day that we started the empennage it's essentially finished - right on schedule. Not bad for a spring and summer where it felt like we were never home.
 
Thanks again to all the family & friends who've helped so far, and for those who haven't - you will.
 
Empennage: 2 hrs
 
Wings: 3 hrs