flaps | Andrew's RV-7 Build Log

He’s Alive (Right Flap Rib Work)

July 20, 2012

Hello everyone! I’m back! (But seriously, let’s not call it a streak or anything.)

I’m still here, I promise.

I’ve had a lot of crazy things happen in my life (all of them positive…I’ll mention them eventually) that have been keeping me away from the garage, but today after a nice dinner with the fiancée, I decided a little garage time was in order. The other day, I spent a few hours cleaning off my workbench, so really, the next step was to take the clecoed flap apart, and start prepping it for final assembly.

Here’s the right flap as it’s been sitting for about 6 months.

As I was disassembling, I started to remember where I had left off. Oh yeah, I had done the two half-hinges trick, and had cut away some eyelets.

I’ll be sure to clean these up when I’m prepping the hinge.

I decided that instead of just deburring a whole bunch of parts, I wanted a nice little chunk of work. So, I grabbed the end ribs and the inboard rib’s reinforcement plate (I gotta go back and study the plans to start memorizing the part numbers again) and got to work deburring, dimpling, etc.

Here are the ribs I’m going to focus on tonight.

After standard deburring and dimpling where I could reach, I grabbed my 1″ steel bar with the countersunk hole in it and did my flush-set flush rivet dimple trick.

Here’s the setup. Grab the flush set and let ‘er rip.

And, the final product.

Good end-of-rib dimples. I’ve still got it!

Then, inside for some cleaning, and back outside for the artistry.

By “artistry,” I think I mean “I got more primer on the cardboard than the part.”

While those parts were drying, I continued disassembly of the other flap parts, including trying to remind myself of the controversy about the right flaps internal ribs not having their flanges mirror the flap plans. I kind of remember that all the left and right flap internal ribs were the same part number, meaning that they wouldn’t be mirrored.

Just a picture to help me remember where I got them from.

After a few short minutes, the end ribs were dry.

I forgot how much I love primed parts.

After I whipped out the Main Squeeze and some AN470AD4-5 rivets, I had a little mini assembly. Wuhoo!

7 rivets! No drilling.

Then, I checked the plans for the nutplate callout, and started looking through my rivet and nuts and bolts bins.

A couple flush rivets and a K1000-4 nutplate, and we’re in business.

Whoa! nine whole rivets!

Just to show you it’s real, here’s the backside.

1.0 hour. 9 rivets. Not quite back on track yet, but at least still interested.

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2 Comments | Wings | Tagged: Alive, finacee, flaps, prime, Rivet | Permalink
Posted by Andrew

Bent Right Elevator Trailing Edge

April 28, 2010

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What a great night in the shop tonight. And, the airplane actually forced me to get something done on the house!

After work today, I needed to stop by the Aviation Depot to buy some hinges, wood, and an 1/8″ dowel rod for elevator trailing edge bending.

Since we’ve been wanting to upgrade the hardware in our house for awhile, I decided to buy the nice hinges, and used the replaced hinges for my bending brake. Here’s a shot of our powder room door, mid-installation.

Top hinge is the new “oil-rubbed bronze” hinge. Bottom hinge is the old (builder standard) hinge. Looks a lot better.

Up close. I like the new one a lot better. (Later, I went around and made sure all of the crosses in the screw heads were straight up and down. It’s an anal retentive thing I do, especially with light switch plates.)

Anyway, after a ton of VAF research, Orndorff video watching, and builder website reading, I settled on the “other” method, which puts the hinges on the long face, and really only bends with the short side of the 2×4 (or 2×8 cut in half). You really only want that much bending the skin anyway, because the bend needs to occur locally at the radius, not away from the trailing edge. If the wood is imparting force in the middle of the skin, you will end up with the dreaded “bulge.”

Here’s my bending brake being assembled. I had six hinges, so why use them. I grabbed these 2×4, which were nice and straight, and just long enough for the trailing edge. I’ll need to replace these for the flaps and ailerons. I read somewhere they need to be more like 5 feet long for those.

Here it is after assembly. On the left, you can see my skin, that needs to be bent. In the middle, the three dowel rods I purchased. While I was standing in the store, 1/8″ seemed too small, so I bought a few different sizes at $0.50 each. Of course, everyone was right on, 1/8″ is perfect.

I’m going to put the trailing edge of the skin in the little opening at the bottom of the brake (as it is oriented in the picture).

First thing, I screwed my bending brake to my 2nd workbench with one of the bending surfaces flush with the bench top.

Bending brake, installed.

Then, I put the 1/8″ dowel into the trailing edge of the skin and taped it in place. (Not shown in the following picture, because I was recreating the process for the camera. Look 2 pictures down for the dowel rod.) Then, you put the skin in the brake all the way against the hinges, and start bending.

This is not a fast process. It takes a surprising amount of force. I thought it was going to be a one shot deal, but it takes a lot of bending. You start with the skin against the hinges, then bend around the dowel. That took a whole bunch of times (I was stopping a lot to inspect). Then, you move the skin a little away from the hinge, and bend again. This allows you to really form the edge around the dowel.

If you pretend there is a dowel rod in there, this would be the first bend.

Here’s where I could get to with the dowel rod in place.

About halfway there.

Then, you remove the dowel rod and keep going, same deal, but a lot more gently, because I didn’t want to squeeze the trailing edge too much (now there is no dowel rod to prevent squash-age.

I thought this was good enough, but this is about 3/4 the way there.

Of course, because I thought that was good enough, I clecoed the skeleton into the skin.

It’s starting to look like something that could be considered an elevator.

But, after grabbing my straightedge, I’m getting some “fall-off” before the radius. This happens because the radius hasn’t been formed well, and then you pull the skin down to the skeleton, and it bends close to the trailing edge. It’s not terrible, but I know I can do better.

It’s not the dreaded bulge, but it is some pretty good “fall-off.”

Another shot.

No good here either.

Near the inboard edge.

Hmm. I unclecoed, and grabbed this shot. I’m about an inch from where I need to be, and the tension I am putting on the skin to pull it to the skeleton is causing that slight bend near the trailing edge.

About an inch.

I put that bad boy back in the brake and kept going. This time, I used two BFPs (the “p” stands for pliers. I’ll let you figure out the “b” and “f”) on either side of the brake and finished it up nicely.

More bending.

There we go. I made up that last inch, and now it rests right where the skeleton would go.

Much better. Perfect, in fact.

Here’s an end-on shot.

How great is this? A perfect bend.

Let’s get out the straightedge.

No fall-off before the radius.

Another place on the elevator.

And again, no fall-off. So happy!

After all that, I pulled the vinyl off of the outside of the elevator skins in preparation for deburring.

Hey! There’s shiny aluminum under there. Let’s start putting this bad boy together.

Total, it was two hours tonight, including bending brake construction. It was a great 2 hours though. I am extremely happy with the results. I have a perfectly bent trailing edge.

Boo-yeah.

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Leave a Comment » | Empennage | Tagged: ailerons, Aviation Depot, bending brake, clecoed, Deburring, dowel rod, Elevator, flaps, hinges, Orndorff, skeleton, skin, skin. Vinyl, Squeeze, trailing edge bending, VAF, Workbench | Permalink
Posted by Andrew

EAA 1426 Fly-in Drive-in

April 10, 2010

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So I’m writing this almost a week later, but I’ll try to capture my experience last Saturday.

I woke up Friday afternoon set on having some contact with airplanes, so with a quick search of the EAA calendar, I had a fly-in-drive-in to attend. One of my buddies who owns a C182 was busy and said he wouldn’t make it, so it looked like I would be driving.

Here's 7am in NC looking around my garage corner. Not too bad, although the fence needs painting. Maybe next year.

A half an hour (and Chik-Fil-A biscuit) later, heading north on 77 toward Pilot Mountain.

Look closely at the vehicle in front of me. Crap, a State Trooper. no speeding today.

Another shot of pilot mountain.

Once in mountains, there are a couple nice vistas looking back toward the south and southeast.

77 looking south on the way up the mountains.

Once I pulled into the airport (Twin County, HLX), I met a couple people standing on the ramp and up pulls a beige 182 with a 3-bladed prop. Wait a minute, my buddy Jon has a beige C182 with a 3-bladed prop.

That plane looks familiar.

I wonder who is going to get out.

It's Jon!

(Had to get a picture of him standing straight up.)

Anyway, while I’m a member at EAA 1114, their meeting isn’t until next weekend, and the EAA 1426 chapter fly-in promised pancakes. After some talking with Jon, we stumbled across this piece of machinery.

I’m going to try to capture the jokes about it. I take credit for none of them.

UFO (Unidentified Frying Object.)

So the joke goes that there was a retired Air Force officer who, as part of chapter 1426’s winter activity list, designed and constructed this beast to contend with some of the other pancake cookers out there.

Someone made a pretty funny joke about it being a disc-shaped metal object seen near the airport, and that it was a UFO (Unidentified Frying Object.) I actually spilled a little coffee out my nose at this.

Somebody then pointed out that it must be an advanced design project from the Air Force.

The the Air Force guy piped up and said…

"Nope, it's leaking oil. Must be from the Navy."

Much giggling ensued. No offense to the Navy, or any armed services branch.

Anyway, I got a couple action shots. The cooking surface is a 3/8″ aluminum disc (not aviation grade, the health department won’t approve that as a cooking surface because of some anti-corrosion additives or something). I was interested in that, but couldn’t find any more details. Anyway, th disc spins about 1 RPM, which, with 4 burners (note the manifold in the lower part of the next picture) at 90° from eachother, yields <counting>…18…19…20 pancakes every 3 minutes.

Two times around on the first side, then flip and one more time around.

Action shot! (That's a nice spatula, too.)

Look at how perfectly they are cooked.

Anyway, I had to get a picture in front of it. Here I am, for only the second time in the blog. Sorry I didn’t comb my hair.

Who, other than me, would say, "Hey Jon, take a picture of me with the pancake cooker!"

Then, they showed me a partially completed RV-7 kit. They inherited it from someone, and are thinking about selling it. (I think they are more interested in completing it within the chapter, but they were interested me in at least taking a look.) If anyone reading this wants the contact info for them, let me know, I can put you in touch.

RV-7 horizontal and elevators.

An aquajet (ride for kids).

The wings.

More wing pictures.

Even more.

The vertical, rudder, flaps and ailerons.

These look like the older style wingtips to me.

Oops, forgot to rotate the picture.

Then we walked back to the main hangar, and I grabbed some pictures of the various projects there.

One of two helicopter projects in work.

This is "one of the first non-straight-tal 172s." Even though I used to work for Cessna (I was on the jet side of things), I can't remember what date that would have been early 60s?

I don't remember what I was trying to take a picture of here. Maybe the hangar doors and a 172...and half a ladder. Here are some hangar doors and a 172...and half a ladder!

Ooh, a King Air.

Looking back outside. The pancake cooker is in front of the helicopter being prepped for paint.

Here's the inside of that 172. No priming. No corrosion. Hmm.

A closeup of one of the helicopters.

Inside for breakfast, I got a picture of the sausage and egg chef and the EAA banner they hang up for meetings.

I'm hungry.

One of the very nice ladies there helping with breakfast came to Oshkosh in 2008 and got a picture in front of the Honda Aircraft Company’s HondaJet (HA-420). That’s our proof of concept aircraft.