aileron | Andrew's RV-7 Build Log

Aileron Mounting and Flap Seal

December 28, 2011

Well, I have all week off this week, and due to travel, random other activities, and general stay-at-home-dad responsibilities, I only managed to start working on the airplane today, Wednesday. My original plan was to get in 40 hours on the airplane this week, but I don’t think that’s going to happen, especially since I only managed to fit in 4 hours today. Anyway, I (we) decided that I’m going to start cleaning out some of the airplane parts from our workout room. In that light, I decided it was about time to start storing the right aileron on the right wing.

So, I pulled out the aileron plans and started studying the hardware callouts.

This is for the outboard end. No spacer needed.

Here's the inboard side.

I think this is the hardware for the outboard side.

And the hardware for the inboard side, plus the AT6-058 tubing to make a spacer.

I did need to enlarge the weldment bolt holes to the proper size, so I grabbed an AN3 bolt and measured it’s diameter.

Looks like .186"

I tried a few bits and found that the proper drill bit for a AN3 bolt is a #12. Later on, I found out that the proper drill bit for an AN4 bolt is a 1/4".

One of the things I have on my list of things to do is to countersink and set the lower inboard rivets on each of the aileron hinge brackets.

At first I was kind of skeptical that you needed a flush rivet head here, given all the room in the picture…

There isn't anything even remotely close.

…but, after swinging the aileron through its full motion, I noticed that full up (trailing edge up) aileron has minimal clearance there.

Those Van's guys are smart.

Back to the hardware. One of my stocking stuffers from the ~~girlfriend~~ FIANCÉE was this wonderful double-drive ratcheting screwdriver that you’ve all seen on the commercials recently. I have the snap-on one, which is REALLY nice, but this one is great for fast (double drive!) fastener insertions. I’ll use the snap-on when precision counts, and the Kobalt where speed is my friend.

DOUBLE DRIVE!!!

Anyway, I used that with a socket on the end to quickly secure some of the aileron attach hardware.

I’m not sure what order these pictures are in. Here’s me cutting some of the aforementioned AT6 tubing for a spacer.

Action shot!

I don't think I got the edge of the spacer just right when deburring. I might redo this. (This was also the only place I had to make a washer substitution. I used a skinny washer to the right of the aileron attach bracket.

Here's the after shot of the outboard end.

Hey, look at that! It looks like an airplane!

Okay, here, the ADD set in, and I needed to so something else. Time to pull out the flap seal. After edge finishing and scuffing…

Tada! Time for cleaning and priming.

Don't let the sun fool you. It was freezing out today.

Serisouly, there pictures are way out of order. Here are my rivet counts after I was done with riveting the flap seal on.

29 total rivets set, 1 drilled out.

I didn’t get a good picture, but I didn’t get the rivet gun lined up right, so the edge of the set just chewed through the rivet head.

Anyway, a nice clean drill-out.

Here’s the finished product.

29 rivets closer to the end.

Next, I was trying to figure out how to line up the aileron, so instead of copying some other people’s cleco and a straight edge trick, I decided to do it by the book. Grab a straight piece of wood, drill the holes for the tooling holes in the wings, then line up the aileron with two tangential lines.

Easy enough, right?

Well, kind of. Turns out, I had used one of the tooling holes as the attachment hole for the angled bracket for the wing stands.

See? 1/4"

The upper one is still #21, though.

So, I drilled two holes at the appropriate distance for an AN3 bolt, then drew my tangential lines, then enlarged the lower one to 1/4″.

Worked well for me.

But I quickly realized that with the wing nose-down, the aileron is NOT neutrally balanced. Since there is a moment on the aileron, if I clamp it to my piece of wood, it’s going to bend the piece of wood for a false reading. Looks like I’ll have to actually construct the bellcrank and pushrod.

So, I fished out the bearing from beneath my workbenches and cleaned off the tag.

Also, I found the bellcrank attach brackets.

And cleaned off more tags.

I was trying to locate the AN3-6A bolts that are called out for the bellcrank attach brackets, and I couldn’t find them anywhere.

After about 30 minutes of build time wasted, I remembered that I had one more bag left. I thought this was just the close tolerance bolts, but alas, there were plenty of other AN bolts in there.

This bag hid from me for 30 minutes.

So then I spent about 20 minutes sorting though these bolts.

There are some AN3-6A bolts on the left there.

I have some residual confusion about bolt length, though. Here’s a known -4A and -7A.

Makes sense.

Here's the -6A. This is all good.

Oh, I guess we’re jumping around in pictures again. I’ll bring up my confusion later.

I got the brass bushing out of my storage box and deburred the edges a little.

Shiny is scotchbrited, dull is out of the box.

After inserting into the bellcrank….

Looking good, needs to be drilled to final size, though.

It just barely sticks out both ends of the bellcrank as designed.

Perfect length out of the box.

I did need to drill them out to a #21, though, for the long bolt that goes through them.

This was more difficult than I imagined it to be. I did use wood to clamp these in the vise, and lots of cutting oil for the drill bit.

So here’s where my confusion came back in. I was supposed to use an AN3-32A bolt, but when I held up the longest bolt I could find, (and after verifying that the longest bolt was the appropriate size for the assembly), I held it up to the bolt gauge thing, and it told me it was an AN3-28A. Hmm. I’ve got my three threads on the outside of the nut, so I guess I’m okay, but I’m still confused.

Anyway, now that I’ve got the bellcrank available, I need the pushrod.

Here's a closeup of the pushrod I'm going to make.

Here's the rest of the W-818 assembly.

After carefully measuring and cutting, here are my two pushrods.

One left, and one right.

After drilling two 90° #30 holes…

You can also see an AN470AD4-12 rivet.

Then, after some rivet squeezing and priming, I propped it up on my handy-dandy cleco storage units for drying.

It's like watching paint dry.

A picture of the rivet shop heads.

Oh, and one more spacer for the actual attach point for the aileron.

More spacers!

Here’s the attachment for the aileron.

This angle is weird because I've flipped the entire aileron up and around its axis.

But, after I got the pushrod installed…

Looks like an airplane!

Here’s the bellcrank area. Looks like I dripped some primer in there.

Van's tells you to prime the inside of the pushrods, too. So I poured some in there, then tried to pour it out. None came out until I installed it here, and some seeped around the edge of the pushrod fitting. Oops.

Hey, not to far off for the first try.

Within a degree or so...I'll fix this first thing tomorrow.

4 hours total today, 3 of which were on the ailerons, 1 of which was for the flap brace. 29 rivets set, one drilled out. Yahoo!

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2 Comments | Wings | Tagged: aileron, AN3, AN4, AN470, bellcrank, Hardware, primer, Rivet | Permalink
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

Some Left Aileron Deburring

September 25, 2011

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Well, I’ve definitely learned something about myself this weekend. After I pass the initial excitement of a completed assembly, I have a hard time repeating all of those little boring steps to get the second one done.

I’m pretty sure I experienced this on the second elevator, I’ve definitely experienced this on the left/right wings, and right now, I’m having trouble motivating enough to get finished up on this left aileron.

BUT.

The other half of this airplane isn’t going to finish itself, so let’s get to it.

A few weeks ago, I left off on the left aileron after having matchdrilled everything, so today, I got it all disassembled, and started in on the tedious crap.

Here are most of the parts (except the skin) after disassembly. Let's start prepping.

The nice thing on this second aileron is that I’ve already done everything once.

No sweat here countersinking the counterbalance pipe.

A little deeper than flush, as usual, to make plenty of room for the skin.

Oh yeah, I had forgotten to flute the nose rib between the two x’s, so I marked them with…well…x’s, so I wouldn’t forget to flute, then drill them as I was taking everything apart.

I clearly went a little overboard on the flute there. I "unfluted" a little before matchdrilling.

Then ( I guess I was bad at taking pictures today), I clecoed the skin back onto the counterbalance pipe, balanced the assembly on a 2×4 (which was part of my bending brake I had attached to my workbench), and dimpled using the die from my borrowed c-frame.

They all turned out great, like the ones on the right aileron.

Then, I got to deburring and dimpling. I worked on the ribs and reinforcement plates, leaving the spar and skins until another boring day.

asdf

One kind-of-boring hour tonight. Maybe the next few sessions will pick up.

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Leave a Comment » | Wings | Tagged: aileron, boring, Deburr, dimple, scuff | Permalink
Posted by Andrew

Finished the Right Aileron

September 17, 2011

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Wuhoo! As you can tell by the title, I got a TON of airplane work done today. I actually did everything in three 1-hour sessions. Worked out well for everyone.

In the first session, I unclecoed the work I had done last night, and built a little stand (like every other builder) to screw the spar to for riveting help.

I copied this from many builders.

Whoa, I guess the next picture I took was of some shop heads. Moving right along…

My old bucking bar (non tungsten) has an angled edge to it, so I could wedge it in here to buck. It worked perfectly.

In terms of shooting the rivets from the outside, I copied Mike Bullock (about 3/4 the way down this page), but instead of building a little wood stand, I just stacked 3 2×4 blocks. It worked for me with my gun size/flush set, etc.

I'm about halfway through the top skin-to-spar rivets here, demonstrating the technique.

To buck, you reach up, around, and under the lower skin to hold the bucking bar in place.

After you buck, you slide both hands down a few holes and do it again.

I’m glad I’m pretty strict about edge-finishing skins.

This is NOT a cry for help. Well, maybe it is, but it would only be for some sort of arm-hair control product. (I could braid that if I wanted to...)

Alright, moving on, here’s an eerily blue (LED flashlight) picture of the top spar rivets done.

Left side of the picture for the interesting bits.

I didn’t shoot and buck the inboard- and outboard-most rivets. I could easily squeeze those, except for the very edge ones, which tended to sit up from the underlying skin. I devised a little trick to hold the skin down while leaving enough space for a rivet set (of the squeezer) to do it’s magic.

If my side clamp would have been a little longer, I wouldn't have needed the washer, but this worked out okay. (Okay = perfect.)

42 rivets done with no mistakes!

Next up is to get the nose ribs and main ribs riveted on the top side of the aileron.

And thus starts the second session of the night.

CRAP, I forgot to prep the main ribs.

Deburr, dimpl- CRAP, I can’t use a regular die on the aft-most holes. Out comes my steel bar with a countersink in the edge. You remember this from my empennage posts however many years ago…

You stick a rivet in the hole to be dimpled, then put the underside in the countersink, and give it a few pulls from a rivet gun with a flush set.

Not very pretty, but it works great.

I love it when I already have solutions to problems.

This are going mighty smoothly.

So smoothly, in fact, that I HAD to mess something up. Can you see what’s wrong with this picture?

Yup, the two flush rivets on the right side of the picture shouldn't have gone in yet, they should wait for the rib. Dumb Andrew.

While I’m waiting on the ribs, let me set the nose rib rivets on the top side.

5 here, and 5 on the other side. (The two bad rivets are still in this picture, I can't remember when I ended up drilling those out.)

After those nose rivets, they want you to set the top rivets in the other ribs, then cleco everything together and flip it over.

I’m not quite ready for the main rivets yet, but I think I’m okay to cleco everything together.

HA! I TOTALLY REMEMBERED TO USE RTV AT THE AFT END OF THE STIFFENERS!

I remembered this for my first elevator, but then forgot it on the second one. I’ve been reminding myself for A YEAR AND A HALF to not forget it on the ailerons.

I bet I forget it on the left aileron.

Just a dab, behind the...stiffeners.

These pictures might be out of order. After the RTV, I clecoed the bottom part of the skin to the spar and then went outside to fetch the ribs, which were dry (although not primed in this picture below. Weird.)

Right Inboard and Right Outboard. Pretty complicated, right?

Okay, I think we’re back on track now. The ribs are dry, and they are now riveted to the top part of the skin.

16 more flush rivets. 8 on each side.

Then, the third session of the night, and the last few steps of the aileron!

First, flip that bad boy over and make sure it’s flat. I used the MDF workbench, an extra piece of MDF, and some stones.

Things were flatter than Kansas.

They first want you to set all the counterbalance pipe ribs.

This went great, and I didn't feel like I had to round off the rivet heads with a hammer after setting them like other builders...

After those 14 rivets, you’re supposed to set the 6 nose rib rivets, 3 on each side.

6x check.

This is a really long post. Are you guys still with me?

I hope so, this is the fun part.

After those, you set the main rib-to-skin- rivets (16 there, too), which are partially hidden by the top piece of MDF here, then move on to the skins-to-spar blind rivets.

Halfway done here.

A closeup after pulling those. Looks pretty good, right?

That was 42 more rivets.

Then, you step back and cheer!

Or don't cheer, and just take another closeup picture.

Okay, have you guys been counting rivets with me? I couldn’t keep track very well, so I started just writing them on the skins.

My final number for the evening?

150.

With about 10 minutes left before the next half-hour tick (cause I only log time in 30 minute increments), I decided to get the aileron brackets attached. All went well (with the usual AN3-4A bolts, some AN960-10(regular and/or L) washers, and AN365-1032 nuts, except there was one hole that wasn’t quite perfect. It was fine, but just stubborn enough that my pinky (the only finger I could use to slide the bolts in) couldn’t push hard enough.

My solution? Take my economy squeezer with no die in the yoke (the black part), and squeeze the bolt in. Since there is no die back there, the bolt just slides into the hole in the yoke as it’s squeezed.

Worked great!

After some fiddling, I got all of the nuts on, just past finger-tight. I need an in-lb torque wrench and some inspection lacquer.

This is the outboard end. The inboard end is similar, but a little different.

Then, I had to take a step back and look at my completed aileron.

(Triumphant music playing...)

Good day today, and I got to take an airplane part up to the airplane storage room, I mean, the exercise room…

3 hours. 150 rivets, 4 of them drilled out because I’m dumb and didn’t pay attention.

Time for bed.

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Leave a Comment » | Wings | Tagged: aileron, dimple, prime, Pull, Rivet, Squeeze, Trick | 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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Leave a Comment » | Wings | Tagged: aileron, cleco, dimple, prime, skins | Permalink
Posted by Andrew

Dimpled Right Aileron Leading Edge

September 15, 2011

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One picture today.

All I did was deburr and dimple the right aileron leading edge.

Shiny leading edge.

All I need to do now is edge finish and get the mating surfaces primed.

Then, cleco it to the spar, and get the right aileron skin in a place where I can start riveting.

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Leave a Comment » | Wings | Tagged: aileron, Deburr, dimple | Permalink
Posted by Andrew

Mucho Aileron Work

September 11, 2011

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Well, happy September 11th. (And by happy, you know what I mean.) Many thanks to those who pledge their lives to keeping the American Dream alive. I get to build an airplane in my garage because of many courageous Americans- past, present, and future.

Thank you.

Now, let’s get back to living the dream. Time to bend some aileron skins.

I knew when I made the homemade bending brake for the elevators that they wouldn’t suffice, but I pulled that puppy out, mainly to steal the hinges.

The drywall screws are where I screwed it into the side of the workbench.

Warped much?

Anyway, this week I ran by the aviation big box store and picked up an 8-foot 2×8. I had the guy at the store cut 2 feet off, then rip it down the middle to make two 2x4s, both 6′ long.

Back at home, I clamped them together and screwed some hinges to them.

What a nice, straight piece!

I made sure to measure out and draw some perpendicular lines to ensure the hinge axis lines were all in the same line. (The empennage ones were not well aligned. They worked, but it was hard to actuate.)

Alright. Let's get to bending.

Just like last time, I screwed the brake into the side of the workbench so one skin was flat against the workbench surface. This worked really well for me.

Sorry about the messy workbench.

I had purchased a few different sizes of dowel to go in the trailing edge, and after a couple attempts (with the girlfriend’s help), I just couldn’t get things to bend.

I switched to the smaller (1/8″, after first trying the 3/32″) dowel, and I got it a little better, but not all the way.

Finally, I pulled out the dowel, and gave it a shot.

Much better.

Except, I got a little bit of a bow. I guess since I was grabbing the brake at the ends, I was getting more “Squish” on each end.

I still need to go a little further, but see how the middle isn't as done as the edges?

Anyway, I set the spar into the skin and here’s where I was.

Almost there...

After one more effort, I had it perfect.

I pulled out the straight-edge to make sure the flat surface lasted all the way to the trailing edge radius.

Good here.

And here.

Is there an echo in here?

After another bend and a whole bunch of clecoing…I had two assembled ailerons!

I love assembling a new airplane part for the first time.

After some matchdrilling of the top surface, I flipped over, and drilled every other whole of the lower skin to spar holes to #30 (pilot holes are prepunched to just under #40, hence the alternating cleco sizes).

Bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver, bronze, silver bronze, silver bronze, silver, bronze, silver, bronze, silver bronze, silver bronze, silver.

Next up was drilling the steel water pipe- excuse me…”counterbalance pipe” to #30 through the predrilled holes in the skin.

This was much easier than I thought it was going to be. No big deal.

It was time consuming, and I used some boelube, but it was easy.

Then, even though this picture looks just like the one above, I have two matchdrilled ailerons.

tada!

I have a few holes I need to get to (forgot to flute the nose ribs, so I didn’t drill those holes, and there’s one counterbalance pipe hole you have to wait on), but I’ll finish those tomorrow and start the long process of prep for priming and final assembly!

2.5 Hours.

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Leave a Comment » | Wings | Tagged: aileron, matchdrill | Permalink
Posted by Andrew

Deburred and Scuffed Aileron Stiffener Holes

August 29, 2011

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Umm, this is a pretty boring update, but I had to do something outside tonight. I grabbed an oversize drill bit and a scotchbrite square and did some duburring and scuffing of the stiffener holes in both aileron skins.

Tools of the trade.

I told you it was boring. 0.5 hour.

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Leave a Comment » | Wings | Tagged: aileron, Deburr, scuff, Stiffener | Permalink
Posted by Andrew

More Right Top Skin Riveting Prep

August 11, 2011

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Not much tonight. I put rivets in the remaining top skin holes and did some better inspection of the rivets we set a few days ago. All the rivets look great, but I’m less than perfectly content with some of my edges. The tank-top-skin seam has a really tiny step to it. I rolled the edge a little, but I probably could have gone a little more with it. Also, my very nice scarf joint turned out to not be perfectly flush either. It’s not anything I’m going to change, I’m just going to have to accept that I’m not going to win any awards.

Anyway, I put the rivets in and put a piece of tape over each one.