Rolled Rudder Leading Edge

April 1, 2010

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All I came out to the shop today for was to roll the leading edge and set the 25 measly little blind rivets. This should be simple, right?

WRONG.

This was by far my worst building night so far in the project (although any night building is better than a night not building). So frustrating. There was a point where I thought I had mangled the skins so badly that I was going to have to build a new rudder.  Read on.

First thing, I’ve read to go ahead and drill all of the holes to #30 and deburr now, because if you wait until after rolling, you may enlarge the holes and/or have a very hard time deburring the holes you’ve matchdrilled.

An example of the original holes on the left, and the #30 drilled hole on the right.

More holes after drilling.

I had to play with the angle a little here to capture the edge rolling. You can see the bright section of the skin just right of the hole. The reflection is catching the overhead light above me and to the right. I used hand-seamers here with great success.

Then, I decided to try a method I found somewhere (although I can’t find it again today) to bend the skins. Here, I’ve got my steel rod ready to be taped to the left skin’s lower leading.You basically clamp around the steel pole to the table so that as you roll, the whole rudder slides toward you, but the steel rod stays close to the table and you don’t end up with a crease.

This would have worked, but my clamps were too big, and I only got to roll a half inch or so before they caught on the skin and prevented further rolling.

My setup. Later, I added longer pieces of tape along the whole length of the spar to minimize different tensions on the very edge of the leading edge.

Then, I put my camera down for almost an hour. I was so frustrated. Apparently, the 3/4″ pipe works great for the areas where the spar flanges is closer together, but not down here.

OMG OMG OMG OMG. I thought at this point that I was going to be building a new rudder. The bends aren’t really that good, and there is no way I’m going to be able to salvage this. You can see the skin rolled nicely near the tip, and then not as much near the spar. It should be the other way around.

After extensive (read: time consuming, careful, dirty-sailor-mouth-filled) working with my hand and duct tape, I finally got it clecoed together.

With the duct tape, I had a piece from the right to left side in between each hole. I would squeeze the skins together, and then use the other hand to go down the line and tighten all of the duct tape straps. back and forth about 10 times, and it finally started to look okay. Phew.

Okay, it’s not so bad now.

Here’s the first rivet (AD-41-ABS) going in. Once you set the rivet, you can see that it squeezed the area around it a little. I’m  okay with that. notice, though, that the edge rolling made the seam look really good. I am happy with that part.

After more blind riveting, I temporarily stuck the lower rod-end bearing in the lower hole. It’s starting to look like a rudder.

Lower rod-end bearing.

Then I finished up the other two sections of the rudder (with equal frustration) and got the rod end bearing in the middle hole.

Middle rod-end bearing.

Finally, I got the whole leading edge rolled and riveted.

Upper rod-end bearing temporarily installed.

It actually doesn’t look that bad.

Not too bad. There is some slight creasing just forward of the spar rivets in a couple places, but it’s nothing I can’t live with. 

Be warned about this part. It sucks, and I don’t want to have to do it again. (Can’t wait for the elevators!)

1.5 hours. 25 of the most difficult rivets I’ve set on the project. I’m looking forward to finishing off the last few missing rivets on the rudder and moving on to the elevators. Not before I bring down the VS and mock them up together. I’m thinking of even upgrading the site to accept videos and putting videos of the mock-up on here. We’ll see.

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Riveted Rudder Trailing Edge

March 31, 2010

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Well, it’s been 3 days since I prosealed the trailing edge, so I mentally prepared myself for the dreaded riveting of the trailing edge.

Here's the trailing edge. Hopefully, the pro-seal is dry.

Next, I pulled out all of the clecos and admired how straight it looks.

Looks straight. Let's take a closer look.

Straight as an arrow. (Before riveting.)

The clecos were easy to pull out, not a lot of pro-seal on them, and there was very little remaining in the holes. The usual step here, however, is to clean them up. Here’s a before picture.

There's a little goop in there, but not much.

Here I am using a #40 in my fingers to scrape some of the pro-seal out.

This was tedious, but I want the rivets to sit nice and flush.

Here about how much came out of most of the holes.

Next up, put the rivets in the holes to prepare for backriveting.

Rivet in, ready to go.

Then tape to protect the skins.

And here’s my new backriveting plate. I wanted a nice long piece. It’s not quite as long as the trailing edge, but I didn’t have to move it around very much.

New 36" backriveting plate.

And my setup. The power tools are holding the skin flat against the table and backriveting plate.

Ready to go.

Let’s re-read the directions. HOly crap, the pro-seal gets everywhere.

I thought it was funny how I got sealant on the sealant step.

Alright, let’s start riveting. First thing, set every tenth rivet about halfway.

Okay... every tenth rivet.

Everything was going smoothly until I got to this rivet. Can you see what I missed here?

How come there is no dimple for the rivet on the right. Uh oh.

I pulled the rivet out, put my male dimple die in the hole, and gave it a good whack with the hammer.

Rivet is out, where is my #40 male dimple die?

There it is. Not bad for forgetting to dimple.

With the rivet back in. This is the shop head side, so you won't even notice. In fact, I dare you to try to find this hole when the plane is done.

Back to riveting. I followed the directions and kept riveting every tenth, then fifth, then third, etc., until they were all halfway set.

A nice halfway set shop head.

Down the line...

Verifying that things are still straight.

Yup. Straight. Although I know why the picture is blurry. Apparently I left the cap off of the MEK. Oops.

So then I flipped the rudder over, and finished up, per the directions. Except a few things started going wrong (which is why I don’t have any pictures.)

First, I must not have had the rudder down perfectly against the backriveting plate. A few of the manufactured heads were protruding from the skins. Luckily, they rivets were only half set, so most of them were able to be pushed back into their dimples and set further after flipping the rudder back to the original side and backriveting a little more.

Next, my rivet gun pressure was set too low (I thought this meant I was being careful). The gun wasn’t getting the job done before it jumped around a little and cause a couple very minute dings. A lot of my other dings have been pretty small, and these are even smaller. I doubt you would notice if I didn’t mention it, but I’m trying to capture my experiences here, so I offer it up as a lesson learned.

Finally, when they tell you to flip the rudder over to finish the half-set backriveted shop heads, I’m not sure how this is supposed to work. With the long backriveting plate, the rudder is being supported by all of the proud shop heads, so if you rivet the manufactured head side, you’ll be adding a local bow to the trailing edge. I didn’t buy this, so I stuck with the first side and got the shop heads pretty well flush. Once that was done, I finally flipped it over to make sure they were backriveted flush.

I have some pictures of the trailing edge at the end, but after I finished, I drilled out and reset the four rivets I had previously marked.

A nicely reset flush rivet. The skin got a little scuffed here. I hope this polishes out. (Although I am now thinking paint for the rudder.)

Here’s me drilling out  the lower nutplate mounting rivets. Notice the missing nutplate.

First, a #40 through the middle.

Then pop the heads off with the back of the drill bit.

Then, use a #30 to finish drilling out.

AH! I broke a drill bit. At least I was wearing safety glasses.

I must have been adding a little force of my own.

Okay, now I can install the nutplate.

Here it is clecoed from the outside.

I had read people say “the -7 rivets were too short here, I had to move up to a -8.” The warning bells were going off when I originally set these; I was thinking, “these -7s fit just fine, I don’t know what all the fuss was about.”

Of course, I tried the -7 with the nutplates installed, and yes, they were too short. I had to move to a -8, too.

These are long rivets.

A very bad picture of the nutplate installed.

Nutplate installed.

Okay, back to the trailing edge. I really didn’t get a great picture of how straight it was, but it is straight. There are a couple local areas where there is some slight  back and forth, but it is within a 1/32″ and it’s over the course of 4 or 5 inches. You won’t see it unless you scope down the edge, which I’m probably not going to let you do if you come near my plane. Just kidding.

Trailing edge picture.

All in all, an hour and a half today. 56 rivets on the trailing edge. 4 rivets drilled out elsewhere (but already counted in the final rivet count, so I won’t recount those). I’ll try to get a better picture of the trailing edge later and post it here. (The trailing edge picture at the beginning of this post is a good angle and focal length, I’ll try that one again.)

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Rudder Counterbalance and Tip Rib

March 29, 2010

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I didn’t have a very good night in the shop tonight, mainly because I ended up not being able to use the castle nuts on the counterbalance. Read on.

Here's my large order from ACS. Lots of stuff here.

One thing I noticed was that the bolts ACS sent me were not the same size as the bolts that vans sent me. I need to look into this before using any of them. It might be something obvious, but I need to research this a little.

While I was packing stuff away, I found this bearing in my hardware box. Notice anything funny? Like the NUTPLATE THAT IS SUPPOSE TO BE INSTALLED ON THE RUDDER?

AHHHHHHH!

But hey, those are the two rivets that didn’t give me any trouble before, so maybe they’ll be easy to drill out and replace. (Yeah, right.)

Uh oh, spaghetti-O.

Anyway, after much fiddling around with castle nuts, I re-read AC 43-13 and decided these locking nuts would be sufficient for the very permanent installation of the counterweight.

Counterweight installed. Looks like a lot of threads left over, but I double-checked, and it's right.

Before installing the tip rib, I snagged a picture of the RTV I installed on the last rivet of each stiffener set.

Looks weird because of the reflections, but you get the idea.

Another shot, just for fun.

I'm ready to install the tip rib now.

After squeezing 30 of the easy to reach rivets, I snagged this picture of the top of the rudder.

Tip rib mostly in.

Then, out of order from the manual (supposed to do the blind rivets first), I pulled the LP4-3’s out and got those in.

First one...

All done.

I still have some things to do on the rudder:

  • Let the pro-seal dry and rivet the trailing edge.
  • drill out rivets and install missing nutplate.
  • Drill out bad skin rivets (2, I think.)
  • Tips

But, I’m getting close to another dog picture, which is always good.

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More Trailing Edge Work

March 28, 2010

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After last night’s bad fitting trailing edge, I decided to mark where the dimples weren’t sitting properly, and enlarge the countersink ever so slightly.

The problem is that if you make the countersink large enough to accept the dimple perfectly, you create a knife-edge on the wedge. I guess that is why they have you use the aluminum as a drill guide for the countersink bit. After deburring the few knife edges that I got, it ended up working pretty well, but some of the holes are enlarged a little. With the pro-seal and the double-flush rivets, I am not too worried, but it still bugged me a little. It appears other builders have run into this issue as well.

Another shot of the not so good trailing edge before enlarging the countersinks.

Before I thought I would be able to tackle the rest of the trailing edge today, I got some of the “not-reachable-with-the-squeezer” rivets. here’s a shot of some shop heads for the counterbalance skin to skin rivets.

Decent shop heads.

I also finished up the rivets for the counterbalance rib.

More shop heads.

Then, I installed and removed the counterbalance enough to be able to file away some weight so the lead cleared the shop heads of the interfering rivets.

Nice tight fit today.

Here's the counterbalance. The best file for this left big cutouts, so don't judge me for these.

I also finished dimpling the tip rib and got it edge-finished, cleaned, and primed.

Waiting for primer to dry is like watching a pot of water boil. I can't complain though. It's dry to the touch in about 15 minutes.

Even though that was plenty of work for the day, I decided to tackle the trailing edge. I had everything I needed (Lowe’s didn’t have any RTV, but then I remembered I had some at home from my motorcycle habit, so I was in luck).

Here's me attempting to design a way to keep the trailing edges apart. This sucked, and I ended up using scrap 2x4 in between the stiffeners.

Here’s my tools. RTV, MEK, gloves (I used about 8 pairs) and the tank sealant.

Tools.

Don the gloves, and get ready to mix. I had to read the directions about 15 times before I understood. The hardener (I think) is in the tube part of the plunger. You stick the black piece (behind the big tube) into the hole in the plunger, and as you push the plunger from the bottom to the top, you push the black part so the hardener in the plunger is expelled into the larger tube. Confused yet?

Ready to mix. (I've already cleaned all of the parts.

After pushing the black piece (back on the table now) up to start the mixing process, you twist the plunger head while moving up and down, which starts to mix.

This is after about 75 strokes, which is what the directions say you have to do. I had to keep going. (I may have been doing something wrong, I don't know.) I kept going after this to get a more uniform "black death" color.

Then you unscrew the plunger shaft and screw in the nozzle. Okay, where is my caulking gun? I don’t have a caulking gun. OH MY GOD I FORGOT A CAULKING GUN.

Here it is fully mixed.

That’s okay, I just stuck the handle of a large screwdriver down the tube and it worked great.

Here's one side, ready to be spread out. I put a dab between each hole, and then used a scrap piece of aluminum to spread it out nice and evenly.

Another shot. This seemed to be an appropriate amount of sealer.

After that step, things started getting messy, and I had to change gloves a lot (it gets everywhere), so I stopped taking pictures. After I got both sides covered, I laid it into the scuffed and cleaned trailing edge area of the skin.

Look how good that looks. (Also, you can see my 2x4 spacers.)

Another shot.

Of course, I did a marvelous job putting a perfectly penny sized glob of RTV on the last (aft rivet) of the stiffeners before I removed the wood spacers and closed up. (The wood spacer near the bottom of the rudder was a pain in my ass. I lifted up the trailing edge a little with the top skin, so it stopped squeezing the block, and of course the block slid down toward the front of the rudder. Of course now I can’t let go, but I’m too far away from the other workbench to reach all of my long-reach tools. Ever see one of those situations where a guy has one foot in a boat and one foot on the dock, and he’s stretching and stretching? That was me. Except I finally reached a BFS (big freaking screwdriver) and managed to get the block out without contaminating any tank sealant or RTV.

Here's a blurry shot of the bottom RTV glob. Glob is a technical term.

Then, I got the rudder clecoed to the angle, wiped off any excess sealant, and moved the hole thing to the top shelf of my workbench.

Storage, kind of. I'm going to leave this for a whole week while I start on the elevators.

I think it was 11 rivets.  2 hours before the trailing edge, one hour for the trailing edge. The next post is still from today, but I am tracking it in another section and in another column for total time, so it’s getting its own post.

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Trailing Edge Angle Work

March 27, 2010

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I didn’t get in a lot of work today, but an hour on the trailing edge isn’t too shabby.

First thing, unpack the Lowes bounty. I picked up a 6′ piece of aluminum angle (for the trailing edge work) a long (36″) backriveting plate, a 36″ 3/4″ diameter steel stake for leading edge rolling, and a smaller backriveting plate that I will be returning (picked that one up before finding the longer one).

Lowes bounty.

I grabbed the aluminum angle, and drilled both sides to the dirtier side of my MDF toolbench.

The cleco on either end will help it stay put.

Then I used the  trailing edge (pre countersunk) to drill the trailing edge hole pattern in the aluminum angle.

I lined up the trailing edge with the aft edge of the angle so I could ensure things were straight both left and right and forward and aft.

Here’s the angle after being Matchdrilled.

Let's do it.

Next up, countersinking the trailing edge wedge to accept the dimple of the skins. I grabbed a piece of stiffener (.016″) and used my standard dimple dies as a test piece. First, I measured the very outside diameter of the dimple.

0.2165"

Then, I conservatively deepened a countersunk hole in the trailing edge until it reached 0.2165″

Here's .187.

A little deeper...there we go.

After finishing both sides with this depth, I clecoed the skin together. Hmm, This doesn’t look that good.

There's a pretty big gap in some places.

I was frustrated this didn’t work out perfectly and I had some socializing to do, so I walked away. I’ll come back to this tomorrow.

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Got some more skin…riveted

March 25, 2010

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Before dinner, I managed to finish off the last few things on the right rudder skin and get it clecoed and riveted to the rudder skeleton. I still have to install the counterbalance, finish and prime the tip rib, and get those installed before moving on to the trailing edge, and then leading edge rolling.

I’m holding off on the counterbalance because of the fasteners. The plans call out a AN509 screw and a AN365-1032 self-locking nut to hold the counterbalance in.

I know the FAA (AC 43-13) has deemed that an acceptable method for securing something permanently, but given the fact that I won’t even be able to inspect these fasteners (well, I could tell if they were loose if the screws turn from the bottom side, but would have to open up the tip rib to tighten them if needed), I wanted something a little more permanent (maybe not actually any better, but I’ll be able to sleep better at night).

I’m going to use MS17825-3 Locking castle nuts. They are also self-locking, but these will allow me to drill a hole in the screw and insert a cotter pin. I would bet that I also stick some red loctite on them. It would be a good bet.

Then I started looking around at the other fasteners used on the tail. All of the flight controls are installed using self-locking nuts, no cotter pins or safety wires anywhere.

I thought it would be easy ($20?) to put in drilled bolts with self-locking and cotter pinned nuts, so I made the following order from ACS. This should cover all of the counterweight and flight control connection installations for the tail.

17.00 of MS17825-3 LOCKING CASTLE NUT
1.00 of MS17825-4 CASTLE NUT
1.00 of AN3-10 BOLT DRILLED
4.00 of AN3-5 BOLT DRILLED
6.00 of AN3-7 BOLT DRILLED
100.00 of MS24665-132 COTTER PIN
1.00 of AN4-14 BOLT DRILLED

Then I got started on riveting. I didn’t take these pictures until after I had gotten everything done, so no intermediate shots. Sorry.

Bottom edge of the right rudder skin. This time, I didn't forget the fairing attach strip. (I need to figure out what to do about the last two holes. I'd like to avoid blind rivets, but may need them after all.)

Looking up the rudder from the bottom of the right side.

I got all the rivets my squeezer could reach. I'll have to buck these tomorrow.

There were only two rivets that needed to be drilled out (you can see both marked on the first picture today).

Here's one; the forward-most fairing attach strip rivet on the right side... the squeezer slipped.

Here’s the other one. It’s just sitting a little proud. Probably okay, but I am anal about this stuff.

Guess what I am planning on doing to this rivet.

Also, I noticed something about the alignment of the rudder top fairing attachment holes. Look at the holes on the left side of the picture (lined up from one side to the other) and then look at the holes on the right side. It appears as if Vans put the aft-most holes in slightly different spots so the fasteners wouldn’t hit each other when installed due to the low clearance in that area.

At first I thought there was something wrong, but then realized they were just thinking ahead. Bravo.

One hour today.  18 rivets on the bottom edge, 48 on the leading edge, and 6 where I could reach on the counterbalance skin to right rudder skin lap joint. That makes 72 total for tonight. 1333 total set, 85 drilled out for a batting (drilling) average of 6.38%.

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Got some skin…riveted

March 24, 2010

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After having performed the last of the rudder skin prepping the other day, I was ready to get riveting.

First thing, I pulled most of the clecos off of the leading edge so I could have access to the upper forward edge of the skin. It’s hard to see in this picture, but I gently “edge-rolled” the leading edge so the lap joint would sit flush after riveting.

Be very gentle here so you don't get a crease.

Because my trim job on the blue vinyl was a little long, I trimmed about another inch off. You can see the very slight edge roll in the reflection of the two clecos just left of the joint. I’m happy with it, and it sits very well on top of the counterbalance skin.

Man, there is a lot of dust.

Then, I started riveting. Here, You can see I’ve riveted the counterbalance skin to counterbalance rib joint, and every other hole down the leading edge. I’m just removing clecoes here to start finishing the leading edge.

Beautiful day to be working outside.

This was after about 50 rivets had been set. We headed in for dinner at this point.

Nice rivets, so screwups, but not as nice as the backriveted stiffeners. I thought about backriveting here, but I would only be able to backrivet one side, and I didn't want them being dramatically different.

One more picture before dinner. If you look closely, you can see the very nice lap joint.

And a picture of the shop heads. A few of these (maybe 5th from the right and similar) will need a few more hits with the gun, they don't look quite set enough.

Before dinner, I went and got my mail, and my internal rudder stop had shown up. $25 to get the external stops off the airplane. Worth it for me, although I think Craig is making a killing on these. If you want one, order them at the VAF posting.

Internal rudder stop. I'll install (and take plenty of pictures) once I get the rudder done.

After dinner, the girlfriend wanted to work out in the garage some more (what a crappy girlfriend; she wants to work in the garage all the time… /sarcasm off), so I finished up the left side of the rudder.

Left side of the rudder, done.

I was going to take more pictures, but I got distracted because I riveted the skin to bottom rib WITHOUT INCLUDING THE FAIRING ATTACH STRIP.

Awesome, that was 16….no….17 (i messed one up putting it back in) rivets I had to drill out.

Perfectly.

Good.

Rivets.

<sigh>

But, I did get solid rivets in all of the holes near the horn brace. My 3″ yoke with a 1/2″ flush set kind of looks like a longeron yoke, so I was able to reach all of these.

Here's a closeup of the attach strip after everything was all said and done.

All in all: 84 rivets set, 17 drilled out (ugh!) over an hour and a half.

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