cleco | Andrew's RV-7 Build Log

Some More Right Wing Lower Skin Riveting

November 4, 2012

Well, I decided that with an hour to kill this afternoon after the Bears game (they whooped up on the Titans), I would go outside and see if I could do something productive.

I managed to get a few more rivets set in the bottom skins.

Let me apologize in advance, the pictures are in a weird order.

First up, I peeled back the skin to make sure I could get to the rivets I was interested in. But also, AND THIS IS KEY, you have to make sure that once you set those rivets, you won’t back yourself into a corner where you can’t reach another set of rivets, so I checked (what I’ll call) “future” rivets.

Basically, I reach through the lightening holes and then up with the bucking bar.

I can reach both sides for about 4 rivets before I have to reposition a little.

Also, be sure to be carfeul with the skin. Even the manual warns about creasing it.

After spending so much time cleaning, I was amazed at how quickly the workbench started filling up again.

I’m going to make an effort to keep everything clean at the end of each work session.

After 30 minutes of (loud) shooting and bucking, I called it quits on the loud stuff for the day.

I did the last wingwalk rib, and the main and aft spar rivets just outboard of that rib. I colored the heads black where I set them, just to help me count. This was 40 rivets.

Since the skin doesn’t have to be peeled back as much anymore, I set another 13 rivets of the hinge. (I’m getting good at installing and removing the flap. Not that I have to, I just like to store it on the wing. Seems the safest there.)

I also pre-loaded the next bay of rivets.

If you’re counting ribs, I am now halfway (4 of 8) done with the lower inboard skin. It’s going to get easier moving outboard, too.

I like seeing the clecos slowly disappear.

1.0 hour. 53 rivets. It’s not really a streak until it’s three days in a row, so don’t jinx me.

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Leave a Comment » | Wings | Tagged: cleco, flap, hing, Rivet, shoot and buck. | Permalink
Posted by Andrew

Drilled Right Flap to Wing

January 17, 2012

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Warning: My blog is not a drinking game.

But, if it were, and you had to take a drink every time I logged some build time…

You would not be very drunk.

Hello, everyone. In case you forgot (has it been two weeks?), I’m Andrew, and I’m building an RV-7. Today, I actually got a lot done on the airplane.

It was really only a few drilled holes, but they were important for two reasons.

1) Everyone freaks out about drilling the flap to the wing, and

2) I drilled the flap to the wing prior to the flap actually being riveted together. I know it’s out of order, but I made the decision that the flap was super-sturdy and aligned when it was clecoed together.

(Also, it’s late, and I’m at the step where I need to make a lot of noise with the c-frame, so drilling was quiet by comparison.)

Let’s get to the pictures (and video!!!!).

First up, I wanted to knock out some of the smaller tasks that need to be completed before moving on to priming and assembling. First up is to cut down one of the spar brackets to final size.

I wish I had take a picture of the original piece, but here’s after the cut.

I'm still using my jigsaw for these.

After some scotchbriting.

Then, I moved on to dimpling the spar (I had deburred the holes a few centuries…I mean weeks ago.

Dimple holes. No biggie.

Also, I countersunk the appropriate holes for the nutplate around the flap rod-end attachment hole.

Standard flush rivet in the background, an oops rivet up front.

Here’s where I made a big decision. I was looking for something quiet to do, so I decided to cleco up the flap and just set it on the wing.

First, I needed to get the lower outboard skin clecoed in place.

Clecoed.

Then, I just clamped the flap in place.

Whoa. Looks cool. Like a real wing!

At this point, given the sturdiness of the flap, I decided I could drill the flap hinge to the wing. Even if I totally hose it up, all I’d have to do is order a new flap hinge. (I can order that along with my new RUDDER, which I still haven’t accepted as needing replacement yet. What was that….a year ago?)

Anyway, let’s just clamp everything in place and see if it still makes sense.

Looks like I need 1/4."

Two 1/4″ drill bits, two Popsicle sticks, and two clamps later, I had a flap ready to be drilled.

For the record, this was not the first, nor the last, of the many attempts at a) a good picture, and b) aligning the trailing edges.

Looks pretty good though. Not perfect, I need better alignment along the trailing edge.

For most of my alignment, I used my 4′ level on the trailing edge, then used my iPhone level app to get down to the degree.

Here I'm making sure the transition lines up, then I'd move the level to the flap, measure the absolute angle, then move it to the aileron, and compare the absolute angle.

After about 10 iterations, I drilled the first hole.

Sorry about the blur. The good news is that it's still making sense and aligned.

After working a little down the line (Drill, cleco, measure, measure, measure. Drill, cleco, measure, measure, measure), I stood back to take this picture.

Looks straight to me.

Almost forgot, another one of the measuring tasks was to measure the gap between the flap skin and the lower wing skin.

0.2965" the whole way. Can't get any better than that.

A little interesting note…the flap brace didn’t perfectly line up with the lower wing skin, so I had to improvise a little.

I didn’t want to be matchdrilling the hinge through two other holes that didn’t line up, so I wanted the whole flap brace perfectly in position prior to drilling. I grabbed the smallest -AD3- rivets I had and stuck them in every other hole to act like clecos (I could have use clecos, but that pushes the hinge away from the backside of the flap brace.)

This kept my skin and flap brace holes aligned all the way down the row. As I’d get close to the next rivet, I’d just pull out the rivet.

This worked great for me, but your mileage may vary.

Of course I forgot to take a picture when I was done. I did “lower” the flap all the way to measure, and then mark, the three hinge eyelets I will be using for future hinge pin access.

I've marked them for future modification for the hinge pin insertion, but you'll have to wait another day for that.

Here are some of my “after” pictures.

Looks straight to me.

Looks so good.

Like a real wing.

I was so excited about it, I had to get a video.

So, 2 very productive hours. I’m sure some of the builders out there will insist that all will go to hell after I rivet the flap together, but I don’t think that’s going to happen. So far, all the match-hole kit parts are lining up perfectly, and the clecoed flap is very sturdy and true.

Now, I need to get back to prepping the flap for final assembly. But first, I need sleep. Goodnight.

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Posted by Andrew

Riveted Some Things On the Right Rear Spar

December 14, 2011

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Tonight was a pretty exciting night. Not only because I got the flap brace and aileron gap fairing matchdrilled, but because I got to set 32 rivets I had previously skipped (see my previous rear spar riveting post from almost a year ago).

On to the pictures…

Here I am matchdrilling the flap brace.

I admit, this was a little posed.

Next, I matchdrilled the two aileron attachment brackets. For both brackets, I had to do a little filing to make sure the top edge fit nicely in the radius of the rear spar.

This is all that was needed.

After getting everything on the rear spar matchdrilled, I removed the components and also took the lower skins off. Now I’ve got great access to the rear spar rivets I’d previously missed.

I didn’t really miss them, it’s just that the spar was facing down, and I didn’t have a good way to squeeze them with my no-hole yoke. I could have shot and bucked them laying on my back on the floor, but I knew an opportunity like this was coming soon (well, almost a year later).

bottom skins are off, time for some riveting.

This bottom rivet was one of the troublesome ones before. I shot this from the top side, and it was a piece of cake.

I think there were about 11 of those or so, with 6 more on the rear spar reinforcement bar. Next, though, was this dreaded rivet.

If you remember from that last post, I had butchered this pretty badly 2 or three times, and Van’s had responded that a -5 rivet would work well here if the hole was too enlarged. (They also said a slightly undersized rivet head would be okay if you could engage the entire circumference of the hole.)

Yikes.

First drilled with #40 to make sure I'm on the center.

Then to #30.

Pretty good drillout.

The enlarged hole wasn’t really that enlarged, so I made the executive decision to stick with the -4 rivet.

This time, I set it from the top. Yes, there is a tiny smiley, but it's not worth trying to fix again.

asdf

And a nice shot head on the other side. (Sorry, had to use the flash to see.)

Finally, I deburred and riveted the aileron attachment brackets onto the spar.

After rechecking the plans, I noticed the lower rivet here should be flush. Really? Bummer. I'll have to get a threaded attachment for my countersinks to reach this one.

Same outboard bracket, this time the rib rivets.

Lot's of good shop heads.

Yup, there it is on the lower left. (I didn't show the legend, but this is a flush head).

Whoa, same on the lower rivet here (this is for the left wing, so it's mirrored for the right).

More riveting here.

Nice.

Umm, I don’t know why I uploaded this pictuer…

Redundant much?

1.0 Hours, 32 rivets, one messed up rivet from almost a year ago, finally drilled out. (I’m splitting up the hour into 30 minutes on the ribs, 30 minutes on the wing.)

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Leave a Comment » | Wings | Tagged: Aileron Gap Fairing, cleco, Drilled, Flap Brace, Riveting | Permalink
Posted by Andrew

Right Flap Brace and Aileron Gap Fairing

December 12, 2011

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Alright, before we get too busy getting excited about two posts in a row, let’s talk a little about Christmas. This year, we decided to do a Christmas tree. A few Saturday’s ago, we ventured out into the cold (it was pretty warm) and cut down our own tree (no we didn’t, we bought it from the farmer’s market).

Anyway. There are three interesting pictures from the day.

Jack, incredulously watching us decorate the tree.

Ginger's falling asleep. OMG this is the closest she's been to feather's since FEATHERGATE.

Finally the tree.

Now it needs some presents. Send me some presents.

Just kidding.

Let’s get back to building, shall we?

Tonight, high on the excitement of flipping the right wing over, I decided to get some more aluminum down from storage.

These two pieces are the Aileron Gap Fairing and the Flap Brace.

Part numbers shown for the right wing.

Turns out these have been in the garage for over a year now, so when I pulled off the blue vinyl, there was some residual…well…residue.

A little acetone fixed this right up.

I scuffed these up quickly (I’ll do this more completely when I’m about to prime) and got out the right aileron brackets. The top of the inboard bracket was interfering on my wing (like everyone else’s before me), so like them, I ground down the top corner a little with the scotchbrite wheel.

Here's the corner I ground down.

And clecoed in place.

The outboard bracket clecoed in place.

Here’s the flap brace, looking inboard.

I'll matchdrill both sides, but only rivet the brace to the spar now, the skins will come later.

The flange on the inboard most section is sitting a little funny, so tomorrow, before matchdrilling, I’ll see if I can’t straighten this out a little.

Crooked flange.

Flap brace looking from inboard to outboard.

Then, I clecoed on the aileron gap fairing.

With no trimming, look at how nicely everything lines up. Man, this is easy.

30 short minutes tonight, but it’s better than nothing.

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2 Comments | Wings | Tagged: Aileron Gap Fairing, Christmas, cleco, Flap Brace, Ginger, Jack, matchdrill, Wing | Permalink
Posted by Andrew

Some More Left Flap Work

October 23, 2011

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Yes.

That’s the answer to the question “Hey Andrew, are you building an airplane, or what?

Yes, yes. Of course I am. But, I am taking my time. Not out of “choice”, but out of “holy crap, there are eighteen thousand other things I have to do today”…which was the theme of the day for the last two weeks…

But, I can’t complain too much. Last weekend, I was in Chicago for Zanetoberfest, and just yesterday, the girlfriend and I headed up to Virginia to a winery.

What a hard life I lead!

Anyway, I promised myself (and my girlfriend…no more middle-seat once the airplane’s done, I promise!) that I would get a little bit done today.

So, I headed out to the garage, dusted off two weeks of non-activity, and got to work.

Last thing I had done was to (very successfully) drill the flap hinge to the left flap. It’s still a little long, though, so I need to trim it up a bit.

I know I’m going to use the “secure-in-the-middle” technique, so I used some snips (with a wide berth) to snip the soft hinge, but left the pin intact. Once I can get the wing flipped over, I can figure out which middle eyelet to remove and trim down this pin, but for now, it’s going back on the shelf as a whole until I can get it figured out.

Here's the hinge just after snipping. Notice the intact pin.

Then, We cleco on the top skin and start matchdrilling.

Sweet.

I had to do a little maneuvering to get the spacer lined up (the sandwiched thin spacer below), but I ended up getting it matchdrilled okay, too.

The shadows make these parts all look distorted, but I assure you, they are not.

I also found the AA6x125x1.5x2x10 (whoa, that’s a hell of a part number) and started marking some holes and lines for trimming.

I drew both up before trimming.

I didn't trim the shorter flange down yet. It's 1.5" now, and it needs to come down to 0.75", but I want to wait and see how everything lines up first.

After matchdrilling the three right-most (in the picture) holes from the spar, I flipped it over and drilled the five left-most holes from the angle. I had previously drilled those from markings to #40, so it was easy to drill everything up to #30 all at once.

Aluminum shavings. I've been missing you in my life.

The other portion of this support is delivered from Van’s as a straight piece. Due to the wing-to-fuselage geometry, the spar-to-rib angle is 6.3° or something. Really?

They show you where the bend line should be, so I marked it, then clecoed the only matched hole to the rib, just to make sure the line would be in the right place.

Sanity check complete, let's bend!

Of course, I didn’t take any pictures of my bending, but it worked just like everyone else; one side in a vice, the other side sandwiched between two pieces of wood. Then, some big-a55 pliers…a little finesse…Perfect. 6.3°? On the dot.

OMG, THOSE PARTS NEED DEBURRING!

Then, some more match-drilling…

I haven't been building in a few weeks, but I think this is where I'm supposed to say "TADAAAAAA!"

1.5 hours. I hope this is the start of a string of building days. We’ll see.

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Posted by Andrew

Finished the Left Aileron

October 5, 2011

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Okay. I’m writing this the next day, and you’ve already seen all these steps, so the description that goes along with the pictures is going to be a little sparse. Of course, that’s better than the opposite, where there would be lot’s of description, but no pictures. (Except then, you get puppy pictures, so it’s kind of a win-win all around, right?)

Okay, stop blabbering, Andrew. Let’s get to work!

First up, let’s get those reinforcement plates onto the spar.

3 rivets on each side, plus two for the nutplate...

Then, a couple blind rivets on the nose ribs-to-counterbalance pipe.

The Main Squeeze making a cameo!

Then, They have you rivet the nose ribs to the spar, and cleco on the leading edge skin.

My right skin kind of bent like that too, but when you cleco it to the spar, it all straightens out, I promise. 6 more rivets here.

Then, even though I was sure I’d forget…I remembered to put some RTV at the aft end of each of the stiffeners.

Had to use the flash for effect. Sorry.

Of course, I needed to get both sides of the aileron skin riveted for the rtv to set up at the right angle (probably not that critical), but nevertheless, I was comitted.

I got the assembly up on my previously-built 2×4 stands…

50% clecoed, with rivets and tape in the every-other holes.

In case you didn't believe me, I took another picture. (Really?)

I guess this picture is after I got the 42 top skin rivets done. I did this the exact same was as last time….see the link from above.

No dings, scratches, dents, etc.

Umm, this next picture looks like it’s after I squeezed some nose rib and main rib to skin rivets.

That would be 5 rivets on the nose, times 2, plus 8 rivets for the main skin to main rib, plus two flush rivets on each side...then the whole thing gets flipped over an weighted down.

Next, let’s do the counterbalance pipe to skin rivets.

Nice dimples, nice rivets.

Then, the main ribs rivets (no pictures), and last, nut not least, the 42 blind rivets across the skin on the bottom side of the aileron.

O.M.G. my hand is so tired. 7 more to go...

All done!

(Oh, I also hand tightened the aileron brackets on with the AN3-4A bolts and associated hardware. I still need to buy an in-lb torque wrench…

Pretty left aileron!

I love days like this. I feel like I accomplish a lot.

2.5 hours. 166 rivets… (and my rivet count on the left matched the rivet count on the right. That’s a good thing.)

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1 Comment | Wings | Tagged: aileron, cleco, Finished, Rivet, Squeeze | Permalink
Posted by Andrew

Clecoed Together the Right Aileron

September 16, 2011

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Tonight, my main goal was to get the right aileron to a place where tomorrow I could start riveting on it. The last two paragraphs of the aileron section in the manual are pretty confusing, and you have to read them over and over to make sure you stick to the very specific order of riveting. I don’t want to get started on any of the confusing tonight, so I’m going to concentrate on prep work.

First up, get the right aileron skin deburred, dimpled, cleaned, and primed.

I wasn’t too good at taking pictures of the boring stuff up front, but here are the leading edge and aft aileron skins back inside (from the driveway) to dry after priming.

I had previously pulled the internal blue vinyl off the skins, so my priming lines weren't as neat as they usually are. That drove me nuts, but I resisted the urge to tape them off. Build on, Andrew!

While I waiting, I clecoed the right wing bottom skins. Now the right wing can be removed from the stand and moved to the cradle (once I decide how to build it/use it while I’m building the left wing).

I like how it looks like a wing.

After some drying time, I started following the instructions for assembly. First up, lay the counterbalance pipe and nose ribs inside the leading edge skin.

check!

Then, rivet the nose ribs to the spar. (6x check, although no pictures, sorry.)

Then, cleco the nose skin to the aft skin to the spar.

I was very careful to remember to use my edge roller to put a little bend in the edge of the overlapping skins. See where the cleco is missing? I used this (and the clecoed section to the right) to illustrate how well everything will pull together once rivets are set.

No gap there between skins to the right. Sweet. You can barely make out how I rolled the edge of the nose skin a little.

Once I got clecos in the top half of the aileron…

Whoa, clecos!

I flipped the aileron over and started clecoing the bottom. I know the first step when riveting tomorrow is to take all of these out so I can reach under and around for the top rivets, but I wanted to mock it up to confirm the bottom skin was going to lay together as nicely as the top skin.

I got to the last hole on the bottom skin, and reached in my #30 cleco bucket.

Hmm.

Worked out pretty well, I guess.

Okay. I'm going to leave off here.

The whole aileron is looking really good. All the skins are laying together nicely.

1 hour, 6 rivets.

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Posted by Andrew

Right Float Sender, Riveted Leading Edge to Spar

July 23, 2011

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Guess what? I worked on the airplane today, so the observant of you should realize that I am NOT on my way to OSH. Boo.

No use worrying about the spilled milk, though. More time for me to work on the airplane.

I need to leak test the right tank, but first, I have to finish sealing it up completely. Last post, I got everything sealed except for the float sender. Here’s the plans shot showing the sender, but it’s showing it mounted to the access plate. Mine will be the same dimensions, but entering from the rear of the tank in the second bay.

A couple 90° bends, and I'll be cooking with gas.

That was easy.

To install in the sender, you line up the plastic piece with the slot in the metal housing, and slide the float wire in.

Can't get any easier than that.

Now, let’s clean up and get this thing sealed in there.

Five #8 screws after swishing in some MEK.

After cleaning up a whole bunch, I put the rubber gasket in place with some sealant (couldn’t decide if I needed some or not), then put the float in, then more sealant around the edges, and some sealant for the screws.

Looks good to me.

I retested the sender and noticed 240 Ohms to 80 Ohms (I think I saw something lower before). That’s okay, my EFIS (Electronic Flight Information System) will calibrate the range of fuel levels based on resistance later.

Okay, that was about a half hour, and there are plenty of hours left in the day, so let’s move on. I think the next thing on the docket is to get the leading edge on the spar permanently. I have the leading edge landing light installed, and the tiendown bracket is good to go.

A changing of the plans picture…to the wing rivets and skins page.

Always fun to change plans.

After a few long minutes of getting the spar holes countersunk, I rubbed the scotchbrite pad over the length of the flange, cleaned up with MEK, then taped off to get some primer on there.

Ready for primer.

Sorry the light kind of precludes the primer from showing.

Okay, before I just start riveting the leading edge to the spar, I want to make sure everything lines up again. So, I want to put the tank on the spar, and the opposite skin from where I’m working.

Before I can get the tank on, I need to grab some nutplate for the inboard tank z-brackets.

Looks like AD3-4 and K1000-3 nutplates.

Here they are.

Done. I couldn't countersink very well along the spar bars, so I went a little light and used oops rivets on the very top and bottom (right and left here) holes.

Then I grabbed the outboard lower skin, and got it clecoed on.

Here's just the leading edge clecoed.

Then, I grabbed the tank and put screws in every 5th hole.

And a screw in every hole along the tank/leading edge joint. Everything lines up great and looks awesome.

I told you it looks awesome.

With the leading edge 50% clecoed, I decided it was finally time to show the FAA I’m really building this airplane. Sorry this awesome picture of a pre-squeezed rivet blocked the shot.

My visor says "Foxy's" on it. Anyone? Oh, and that rivet size looks appropriate, let's get to squeezing.

After 65 rivet squeezings, I had the upper leading edge skin riveted to the spar.

The leading edge looks so cool with no clecos in it.

After 65 more rivet squeezings, I had the lower leading edge skin riveted to the spar.

Oh man, I'm so excited.

GOOD DAY IN THE SHOP, high fives all around.

So….0.5 hours toward the tank. 2.5 hours toward the wings.

6 rivets for the spar nutplates, and 65 rivets each on the top and bottom of the leading edge. That makes 136.

Wuhoo!

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Leave a Comment » | Wings | Tagged: cleco, countersink, Leading edge, oops, rivets, skin, tank, Wing | Permalink
Posted by Andrew

Right Leading Edge Inboard Rib Redux

June 17, 2011

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Since I’m out of MEK and I didn’t get a chance to stop by the store on the way home, I decided to work on the new inboard leading edge rib I ordered for the right side. If you remember back on May 13, 2011, I discovered that by having the inboard face of the rib lined up with the edge of the leading edge skin, the drilled holes ended up being too close to the web of the rib. (See this picture specifically.)

Anyway, let’s see if we can’t get a better alignment.

First thing, I kinda-sorta set the rib in place and just made some small marks where the holes would be. This is so I could pull the rib back out and flute it appropriately before drilling.

Marks made.

After edge-finishing and fluting, I stuck the rib back in place where I wanted it, then started matchdrilling.

A few notes:

Since the leading edge skin was dimpled, I didn’t include the W-423 (I just made that part number up) join plate. The rib and skin fit was secure enough that it’ll work out.
I ended up lining up the outboard face of the rib web with the skin edge (make sense?). Said another way, the rib sticks out a little further than the skin.
If it happens to be May 13, 2011 and you discover that your rib drilling on one wing didn’t work out, AND you did both wings the same way, you should probably order both inboard ribs again, instead of waiting until June 17, 2011 (TODAY!) to check the left wing. Doh! I messed that one up too. Now I’ll have another one of these.

Drilled.

Finally, I clecoed the leading edge on the wing (I don’t know why you can’t see any clecos here), made sure my x’s from earlier still lined up over the tiedown hole, and drilled a 3/8″ hole for the tiedown ring.

Drilled.

I still need to tidy it up a little, and probably go to 7/16″ instead of 3/8″ (the tiedown ring is 3/8″), but I’ll leave that for another day.

0.5 hour.

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Leave a Comment » | Wings | Tagged: cleco, drill, Leading edge, Rib, tiedown | Permalink
Posted by Andrew

Inboard Tank Attach Bracket

June 6, 2011

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Well, my order came in from Van’s today. Here are the goods.

It's like Christmas, but in June.

First up, a W-408-1R, NOTCHED NOSE RIB. Turns out, I ruined the other one by not making sure it was all lined up prior to drilling. I have a good idea on how to make this one work out, so stay tuned.

Also included in this order, my flop tubes, and some snap bushings, which I needed to order due to all of the holes I drilled in the wing ribs. (Oh man, now I want a steak.)

Leading edge rib, flop tubes, and snap bushings.

Then, the proseal (black death!), fuel tank leak test kit, and 25′ of black corrugated tubing that should fit nicely in the holes I drilled in the ribs (see steaky link above).

Black tubing, proseal, and test kit.

Even though I REALLY WANTED to break out the proseal and start slathering it all over my workbench, airplane, hands, clothes, and face, I decided to wait until my popsicle sticks and syringes come in from amazon.

So tonight, I decided to work on the right inboard attach bracket.

After studying the plans, I grabbed the AA6…I’m not going to type out the part number. See the picture below.

Yup. That's it.

(Insert silence here where I tried for 10 minutes to figure out what R1 is.)

I’m really sorry to admit this, but I started scouring the internet. Googled “VAF R1 TANK ATTACH BRACKET” and “R1 NOTE DWG 16A VANS RV-7.”

To no avail.

Then, someone’s build site (can’t remember who), admitted that they spent 10 minutes and some google searches trying to find out what the R1 stood for before they realized that it wasn’t a note, it was RADIUS=1 inch.

Duh.

Okay, I’ve got some lines drawn.

Whose cute toes are those?

I think that is T-410 on the top of the picture. I used that to trace mirror images on the 2" side.

Then, I pulled a can of OFF from the shelf and used it to make a 1" radius circle. Then, connected the tangents after drawing a 1/2" line along each side of the bottom. (The drawing is half scale, and it was 1.4" on the drawing.)

After some sawing, I for some reason lost interest and broke out some of the snap bushings.

Two of the smaller size (SB375-4), and one of the bigger size (SB437-4).

Sweet. These will work perfectly.

Nice.

Umm, who took this redundant picture?

Okay, back to sawing.

Hmm. This turned out to be annoying with the jigsaw. Maybe I need a bandsaw.

Done.

Insert about 30 minutes of deburring on the scotchbrite wheel….

Deburred.

So, then I put it in the nose of the inboard rib, and admired how nicely it fit. (Actually, it still needs a little trimming around the edges.)

Looks good.

Okay, I didn’t do a good job of taking pictures here, but basically, I drew a line 1 and 1/16″ back from the tip of the rib, and then drew a line parallel to the front edge, but 2 diameters of the final rivet size (1/8″) away.

Here's where I got the 1 and 1/16" from.

Then, I marked and drilled 5 of the 6 rivet holes, along with the center hole, which is the pilot hole for the 9/16″ hole that the flop tube fitting will fit through.

confused?

Here's a better picture. 5 plus the pilot drilled, and I've laid in the AN nut to see where I can put the sixth (marked) without rivet head interference.

This is me trying to figure out what size hole I’ll need for the fitting.