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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I Hate Making Stiffeners

August 14, 2011

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After last night’s bummer of a screw up (mis-drilling the aileron spar reinforcement plates), I woke up in a cold sweat.

I thought I was going to have to order four more little plates, just to pay some ungodly amount of shipping from Van’s to here.

Then I rememberered the “Trim Bundle” than Van’s sends you. I think there may be some 0.040″ in there.

Sure enough (after measuring, finding some 0.045″, then taking the blue plastic off, and seeing that it was really 0.040″), I had something to continue working on the ailerons.

I went ahead and marked some 0.032" that I found, as well.

After some measuring, marking, and trimming, I have 4 new pieces.

Old and new.

Instead of clamping these to the spar, I decided to just use the old pieces to matchdrill the new ones.

I've clamped the new pieces under the old ones, but in the OTHER orientation.

After some drilling, scuffing, edge-finishing, and marking, I had four new reinforcement plates.

Like new.

I clamped them to the spar, and marked the appropriate holes for countersinking.

There are two holes on the outboard end of each spar, too.

After that, I looked around, and figured there was nothing else to do except start some stiffener fabrication.

I hate making stiffeners (see title of post for emphasis). It takes forever, there are pieces of aluminum flying everywhere, your hands get cut up, but, it’s necessary.

After about an hour of cutting, filing, snipping, edge finishing, and scuffing, I have 32 beatiful stiffeners to go into the aileron skins.

8 on each of the upper and lower surfaces of each aileron.

That sucked, but as long as I can salvage the rudder stiffeners, I think those were my last stiffeners!

2.0 hours.

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Right Tank Inboard Rib Work

June 5, 2011

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After another full weekend of housework, errands, etc., I managed to fit in some work on the right tank’s inboard rib.

First thing, I fished out some parts. Here, Vans has punched out three parts, T-407 and T-410.

Hmm...where are my snips?

I decided to pull both assemblies(?) out and get them all deburred at the same time.

Here are the two access hole doubler rings and four rib reinforcement plates after deburring.

I put two of the reinforcements and one of the rings away until needing them on the other tank.

Then, I took one of the rings, centered it over the stiffener bump on the inboard rib, and used a straightedge to find the center of the circle.

"x" marks the spot.

I know I’m not really working on the left tank right now, but  I decided that since I KNOW the circle cutter is going to be a PITA, I’ll just go ahead and do the left rib, too.

I fished out the two end ribs for the left tank and marked them so I knew which is which.

L1 and L7.

Before mounting the ribs up on the drill press, I needed to find some wood backing. How’s this tank-rib-shaped piece right here?

Pepsi should pay me for the product placement.

Whoa. That sucked. It sucked so bad, I didn’t even take any pictures. Among other things, the circle cutter 1) wouldn’t stay in one diameter, 2) shook so badly I thought my workbench was going to fall over, 3) almost killed me twice.

But, I finally managed to get a decent looking hole.

Phew, I'm glad that's over.

See? Nice hole.

Oops, looks like the hole was a little big. No worries, edge distance for the rivets is just fine.

The hole in the rib is a little big...

After some more cursing, cheating death, and general unhappiness, I managed to get a better (appropriately sized) hole on the left inboard rib.

I think I'm going to throw away the fly cutter now. Stupid piece of crap.

Okay, I’m straying from the instructions a little here. Normally, they want you to take this access cover, hold it against the rib, and use the prepunched #19 holes to drill holes in the rib. Then, hold the stiffener right aligned with those holes, and drill the nutplate attach rivet holes. Clear?

Instead, I’m going to eyeball the clocking of the access cover (so the flat part doesn’t interfere with the indentation in the rib), then just use the stiffener ring for all the drilling. (I need to order a new access cover with no holes in it because I’m using flop tubes (don’t need the small hole), which means I need to move the float sender to the second bay (don’t need the large hole).)

You can see in this picture, the stiffener ring is laid in place, and it looks like the access cover is clocked correctly.

Access cover in the foreground, stiffener ring in the background.

Clamped.

Drilled.

Dimpled the rib, and countersunk the ring.

clecoed some K1000-8 nutplates in place.

Here’s where things got frustrating. Because I wasn’t paying attention, I just started riveting the nutplates in place.

Clearly I didn't countersink enough.

Another view. Yikes.

I drilled out six nutplates (didn’t enlarge any holes in the rib or stiffener), but couldn’t get the rivets out of the nutplates. They got THROWED AWAY!

Sorry, nutplates. You are going in the trash. It's not worth my time to fix you.

Okay, more countersinking, then try again. Still not deep enough? Ugh, more countersinking again, and finally, they were deep enough.

I got frustrated, so I stopped taking pictures. Sorry.

After much cursing and angry mumbling, I got all 24 rivets in for the 12 nutplates.

I had to drill out two more rivets because they were sitting a little proud. In the end though, I’m happy with the results.

These didn't need sealant because the access cover will be sealed over them.

A shop head shot.

24 rivets, 8 drilled out. (one third!? Ugh.)

2.0 glorious hours today.

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Started Left Elevator

May 24, 2010

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Well, it’s monday. And even though I have a couple things remaining on the right elevator, I am going to follow the flow of the directions and move on to the left elevator before coming back to finish both of them.

In addition to the items they want you to do to both at the same time (roll leading edges, install rod-end bearings, etc.), I’ll have to come back to do three things on the right elevator:

  1. Fix a few over-driven rivets (and a couple that bent over that I didn’t catch at the time.)
  2. Figure out how to add RTV to the trailing edges after the fact (anyone have any ideas?)
  3. Trim down the counterbalance. I elected not to do this on purpose.

Anyway, on to the left elevator. Here’s the obligatory changing-of-the-plans shot.

On to the left elevator (and trim tab).

As I only have about a half an hour tonight, my plan was to just cover the basics. First, lay out all of the left elevator parts.

It doesn't look like a lot of work...

Devinyl the skeleton parts.

This picture is almost identical to the one before it, except for the missing blue vinyl on the skeleton parts.

Then, on to real work…kind of. The manual wants me to attach the hinge reinforcing plates to the spar, then move to the outer ribs.

Here you can see the two outer ribs fluted. I haven't straightened out the rib flanges yet, will get to that soon.

Blah blah blah, assemble the skeleton. For now, I didn’t do any match-drilling. I do that hole-by-hole as I take the thing apart.

This one will be more interesting due to the trim spar.

Finally, I found one more of the stiffener angles. I got that devinyled and then cut from hole to hole to form some of the smaller stiffeners.

More small stiffeners. These go between the main spar and the trim spar (ahead of the trim tab).

With that stuff done, I headed inside and caught someone with their hands in the cookie (doggie-treat) jar.

That bottom shelf has the doggie-treats on it. (We have really patient dogs. /sarcasm off)

Lucky you, I got some video.

Anyway, a short half hour of left elevator prep.
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Fixed Right Elevator Trailing Edge

April 24, 2010

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I’ve been lacking in motivation recently due to some badly dimpled holes along the trailing edge of the right elevator. All last week, my error had been hanging over my head, and I was having trouble even motivating myself to fix them.

Saturday afternoon (writing this later) I mustered up some courage and drilled out 13 of the 14 trailing edge rivets on the right elevator. They are really not trailing edge rivets, but the aft-most rivets of each of the 14 stiffeners (7 on the upper skin, and 7 on the lower skin).

You can't even really see the damage in this picture...

Here’s a couple pictures of the damage.

You can see how the dimple kind of tweaked the skin. Boo damaged skin.

The above pictures was the worst one. This one was more typical.

A small ridge below the hole (in the picture) and a small dent above the hole (in the picture).

After getting them all drilled out (13 of them, one of them was good enough to leave alone), I set up the skin with a long backriveting plate underneath the offending holes and used a 2×4 laid spanwise on the stiffeners with some clamps to keep the skin surface flat. Then, I used 4 or 5 long pieces of tape to pull the upper skin back to allow plenty of room to work.

You can still see where the very trailing edge is starting to bend down. This is why I had the problem in the first place.

With no rivets in the holes, I used a small flush set (about 3/8″ diameter) and my rivet gun turned way down to flatten the dents (I’ll call them dents for dramatic purposes, but they were really just small impressions) and ridges (again, really just small high spots) flat. I put the flush set on either side of the existing dimple (which was okay, it was the area just outside of the dimple, where the edges of the dimple die set had tweaked the skin a little, where I was having my problem) and gave it a few taps.

After finishing one side, I took off the protective tape I was using and inspected. It ended up okay. I think if I were going to polish the empennage, it would bug me, but my latest paint scheme idea has me painting the elevators.

I did the other side, and then cleaned everything up, put some rivets back in the holes, and set up each side again with my fancy setup to actually backrivet the last hole of the stiffeners in place. It went perfectly, and I was really careful to hold everything very flat against the backriveting plate.

(By “perfectly,” I really mean “I messed up one of the holes, had to drill it out to #30 and use an oops rivet.” ) I’ll point it out.

Here are some examples of the replaced finished rivets.

This one looks great!

Pretty good. You can still kind of see where the damage was.

Holy crap, how did I do that to the rivet? This is the one that got drilled out again and replaced.

Here's the shop head for the oops rivet. This was my first real oops rivet. Not bad.

This one is okay.

Another very nice one.

It's not blurry in real life, I promise.

Whoa, who scratched my skin? It was probably the male part of the dimple die. That will hopefully polish out, (or it will get cleaned up and painted).

Another good one. In all of these, you can kind of see the larger diameter area that was dimpled.

This one is on the very end, as you can see the devinyling lines.

It looks the same as all the rest, of course, so you’ll never know, and I’ve already forgotten which side (top or bottom) it’s on.

Anyway, I drilled out 13 of the 14 original rivets, then had to redo one of those, so 14 rivets drilled out and reset successfully in an hour today. Not bad. I’ll add pictures when I can get them uploaded. Sorry for the lack of work recently.

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Right Elevator Stiffener Riveting

April 18, 2010

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A few days ago I got a little time in on the project. I’ll see if I can remember what happened. 3 hours, 116 rivets…2 of them drilled out and reset. Here we go. First thing, in preparation for stiffener riveting was to get the skin devinyled. Here’s my devinyling table, wooden stick (won’t dissapate heat) and permanent marker.

Ready to use the soldering iron to devinyl.

After devinyling the inside of the right elevator skin.

For some reason I like devinyling. Don't ask me why.

Here’s the outside of the skin after devinyling. This actually takes a long time to do.

I just devinyled the stiffener holes. I'll devinyl the rest after drilling to the skeleton.

At some point last weekend (can’t remember which day), I was sent to Home Depot (maybe Lowe’s…it was a busy day) to grab some gardening supplies. I took the opportunity to grab some indoor/outdoor carpet for the workbenches.

Here's what I call my toolbench with a new carpet surface.

You should be able to see the “workbench”‘ with carpet on it in future pictures. Anyway, I grabbed the skin and did some deburring (interior and exterior) and some scuffing (interior only, for priming).

Scuffed strip on the left, non-scuffed on the right.

After a few more minutes, I dimpled the skin (no pictures, sorry), and then decided they were ready for priming.

Where is that self-etching primer?

i got the picture order backwards, so you’ll see the skin primed later, but here I am getting ready (or just finishing) stiffener edge prep. I usually use my Permagit block to knock down any ridges, edge deburring tool (pictured below)  to chamfer both edges, and then a scotchbrite pad to smooth everything out.

Right elevator stiffeners and my edge deburring tool.

Here’s the picture of my primed skin.

It looks sloppy now, but wait until I get the vinyl off. Then the primed lines will look nice.

After the stiffener edge prep, the stiffeners got taken inside to be washed with dawn detergent.

Here are half of the stiffeners, being cleansed of their oily fingerprints and aluminum dust.

I decided to take a picture of how much detergent I use. Nothing really important, just camera-happy, I guess.

Dirty stiffeners need to be cleansed of their aluminum dust and fingerprints.

After cleaning, they go back outside for priming.

Boo-yeah, primed stiffeners.

While those were drying (and then flipped and sprayed on the other side), I placed rivets in the dimpled holes and taped them in place.

Rivets just asking to be beaten into submission.

I started to backrivet, and everything was going very smoothly.

Beautiful shop heads.

More beautiful shop heads.

God, I love backriveting.

But anyway, I got through all 116 rivets, then flipped everything over and saw these!

Ahh! Worst rivet ever!

This one is not so bad...

I figured out why this happened, and it falls squarely on me.

While I was dimpling, I didn’t pull the other half of the skin back well enough, so the skin side that was being dimpled was not sitting parallel to the faces of the dimple dies. One side of the die dented each of the last stiffener rivet holes on one side. The rivet in the second to last picture was flush against the backriveting plate, but the skin was dented, or above the backriveting plate.

I’m going to drill out all of the bad rivets on the trailing edge (of course, the worse of the bunch is on the top of the elevator, right where all of you are going to come look at my elevators), and then  try to smooth out the skin by backriveting it with a flush set from the inside out.

It might ruin the skins, which will be expensive. I’ll be sure to take some pictures of the process. Maybe it will save one of you some time and frustration…

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Right Elevator Stiffeners and Priming

April 12, 2010

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Today was pretty boring. All I did was trim the aft end of right elevator’s stiffeners and prime the two spar reinforcement plates.

Here's half of my right elevator stiffeners.

Of course, I finished deburring, edge finishing, and cleaning the two right elevator spar reinforcements. I even got the girlfriend involved. She took the parts inside and scrubbed them down with dawn. Now it really is “our” airplane.

Two spar reinforcements, primed on one side.

While that one side was drying, I finished up with the stiffener trimming. Here’s a shot of my weapon of choice.

Stiffeners and snips.

After I finished my first 7 stiffeners, I laid them into the skin, just for kicks.

Stiffener work is boring, but it means that there is backriveting coming soon, and I love backriveting.

Drink of choice tonight (only during piddly stuff, never during “real” construction): Rum and Coke. Mmm. Rum.

Rum. Coke. Stiffeners. Sharpie. And a damn dirty workbench. (Those splotches are ski-wax drippings.)

Anyway, I think it was an hour tonight, including the 5 minutes of double duty with the girlfriend’s help. I’m gonna get her to help more.

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