Prepping and Priming Some Rear Spar Components

November 20, 2010

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Oh man, I’m furious. I just spent some time doing a huge writeup for this post, and when I clicked, “Post”, it deleted all of my text.

Grrr.

I’ll try to rewrite it, but it is going to have a little bit of an annoying tone.

Anyway, I managed to get out in the shop today for a little. I had previously gotten all of the doubler plates and reinforcement forks matchdrilled to the spar, so today was all about prepping and priming.

Here’s W-707F, which sits on the back side of the left spar. I’ve deburred and scuffed it; all I need to do now is dimpled the outboard holes in preparation for attaching it to the spar and outboardmost rib.

I love scuffed parts. They hide my fingerprints.

Here’s W-707E, which is the doubler plate that sits on the aft side of the rear spar, right in the middle. I’ve marked the cutout for the aileron push tube. Where’s that step drill?

Yup, here you can see my fingerprints.

I started looking around for my stepdrill. I spent good money on that stepdrill, but I couldn’t find it anywhere. On the workbench, under the workbench, on the floor, in some other shelves. I thought maybe I put it in some other tool’s case, so I got out the dremel tool, multifunction tool, jig saw, circular saw, etc. Nothing.

I even accused the girlfriend of selling it on the black market to fund an bottle of Opus One. She insisted that while she thought about it, she didn’t.

I remember putting it in this old small cabinet of drawers (that my dad gave me when I graduated college…thanks, dad!). I spent about 30 minutes just pulling out each one of these drawers, looking for my step-drill. Grrr.

After continuing to work on the airplane (angrily) for another 30 minutes, I finally found it when I came back to the drawers and opened them with my other hand. Apparently my sausage fingers (they’re not, I promise…I’m just mad) blocked my view of the stepdrill, which was right behind the lip of the VERY FIRST DRAWER.

Ugh.

Anyway. Back to the rear spar. This is the forward side of the left spar, outboard end. I’ve deburred the edges of the whole spar, and now I’m deburring all of the holes I drilled.

I always scuff the areas where there are holes I've drilled and deburred. Helps me keep the "did I do this already" time to a minimum.

Oh yeah, I managed to get a couple parts primed today. Like riveting, I always feel like it is a productive day if I can prime some things.

You can also see my primer of choice, Napa 7220.

Here’s the other side of those pieces (after plenty of drying time).

I like priming.

Back to the spar, more deburring holes and scuffing.

I'll finish scuffing the whole spar when I get closer to priming.

This is the middle of the rear spar, around the aileron pushtube hole. More deburring and scuffing.

Jeesh, there are fingerprints everywhere.

Finally, I brought the two primed parts back inside.

Primed parts on the workbench always means we're getting close to riveting. Wuhoo!

After this was about when I finally found my step-drill. I was too angry at myself to keep going, so I headed inside to some grilled chicken, jasmine rice, and creamed corn. Mmmm.

1.5 hours

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Drilled Wiring and Conduit Holes in Ribs

October 3, 2010

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Alright, a little off-topic, but I have to talk about food for a minute. Friday night, I got home from a very hard day at the office, and my wonderful girlfriend announced we are having steak (see? I told you she was wonderful). I also nailed the cooking times on the grill.

Also, that is stuffed squash and zucchini. Amazing.

Then on Saturday, she announced we were having “the best chili you will ever have” for our football date (see! amazing!).

Vandy lost, UNC won, but more importantly, the chili was amazing. Let me know if you want the recipe, but beware, it calls for a cup of strong coffee and a bottle of dark beer. Crazy good recipe, though.

Mmm. Chili.

Okay, back to the airplane.

After a big day on the house, I decided that tonight was all about the ribs.

I scoured a few build sites for ideas, but I basically need to come up with wire routing for the wings. I’m going to use tables to stay organized.

Wiring Requirements
Left Wing Pitot Total Pressure (the “pitot” part of the pitot tube)

AOA Total Pressure (…angled down)

Heated pitot leads

Landing Light (wingtip)

Taxi Light (wingtip)

Nav/strobe lights (probably AeroLeds)

Van’s Stall Warning (can’t decided between this and AOA for stall protection…also, is this left or right wing? Can’t remember)

Right Wing Landing Light (wingtip)

Taxi Light (wingtip)

Nav/strobe (probably AeroLeds)

Autopilot servo

Wingtip NAV antenna? (maybe)

So I clearly need more stuff in the left wing than the right wing, but I decided to drill everything the same way.

As far as the ribs are concerned, there are two flavors of ribs with respect to the tooling holes as provided in the ribs from the factory. (They talk about flavor of ribs in the manual, too, but they are talking about part numbers and flange orientations, I am talking just about the tooling hole arrangements.)

There are 14 total ribs.

The first 11 ribs (counting from inboard to outboard) have three tooling holes in the front part of the web (just behind the main spar). The top and bottom holes are small, and the middle one is 7/16″. I decided (based on a lot of other builder’s sites, and the guidance from the Construction FAQs from Van’s that I’ll enlarge the top and bottom holes to 3/8″. (I’ll get to the other flavor of ribs in a little.)

Here's a before (front) and after (aft).

By the way, I used my brand new #4 Unibit to drill these. I stared at the Unibit from harbor freight (~$15) for awhile, and then decided this is probably something I am going to use a lot and appreciate if it is higher quality. I sprung for the $42 one from Lowes-Aviation.

I think it goes from 3/16" to 7/8" in 1/16" increments.

So, after knocking all of the right wing ribs out, I gathered up the left wing ribs, labelled their positions and orientations, and did those 3/8″ holes, too.

Looking good so far.

The next flavor of ribs are the three outboard ribs (I’m missing one from the picture, look further down.)

They come with one hole in the forward part of the rib. I decided that I would just enlarge that hole to 3/8″ and not try to duplicate all three holes. (The construction FAQ sheet referenced earlier only talks about enlarging tooling holes in this location, not creating new holes.)

2 of the 3 outboard ribs done.

Here's the outboard most rib (upside down from the rest). Van's wants you to leave this one now for help in aileron alignment. I can deal with that.

Now, back to the construction FAQ. Van’s does let you drill a brand-spanking-new 3/4″ hole.

An additional hole may be drilled in the lower 1/3 of the rib between the large lightening hole and the next one aft. This hole may be up to 3/4” diameter to accommodate our wiring conduit (DUCT NT 5/8-50) or Bushing SB750-10 (5/8” I.D.). The conduit is light and flexible. It’s .810 “ outside diameter means that when snapped into place, the corrugations hold it from slipping out. If using the conduit, a dab of fuel tank sealant or RTV should be put on the conduit at each rib to prevent the conduit from being cut through over time from vibrations.

Sweet. I created a makeshift template. and started marking the center of the hole.

(Some people go crazy with this alignment. After reading a lot of other experiences, I reminded myself that this is a flexible conduit hole. They don’t have to be perfectly aligned. Although, after everything was all said and done, they were pretty darn aligned.) Don’t waste a lot of time here on a special tool. Cardboard worked great.

Fancy-schmancy hole alignment tool.

So, after punching 28 3/4″ size holes in both the left and right wing ribs, this is what I ended up with. (Really 3 flavors.)

11 inboard ribs each side with 3 holes and a conduit hole, 2 outboard-ish ribs each side with 1 hole and a conduit hole, and 1 outboard rib with 1 hole (that needs to be enlarged) and a conduit hole.

Of course, I had to lay out all the right wing ribs for this completely unnecessary picture.

Tada! (The left ribs are done, too, but they are stored back on the shelf.)

Okay, now that I’ve drilled the maximum amount of approved holes in each of the ribs, let’s figure out where this stuff should go.

Wiring/Conduit Plans in Ribs
Left Right
Rib # 3/8″ 7/16″ 3/8″ 3/4″ Conduit 3/8″ 7/16″ 3/8″ 3/4″ Conduit
1 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
2 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
3 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
4 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
5 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
6 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
7 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
8 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
9 Pitot Pitot Heat, Stall Warn AOA Taxi
Landing
Nav
Strobe
Servo VHF? Taxi
Landing
Nav
Strobe
10 Pitot* Pitot Heat*, Stall Warn AOA* Taxi
Landing
Nav
Strobe
VHF? Taxi
Landing
Nav
Strobe
11 Pitot* Pitot Heat* AOA* Taxi
Landing
Nav
Strobe
VHF? Taxi
Landing
Nav
Strobe
12 Taxi
Landing
Nav
Strobe
VHF? Taxi
Landing
Nav
Strobe
13 Taxi
Landing
Nav
Strobe
VHF? Taxi
Landing
Nav
Strobe
14 Taxi
Landing
Nav
Strobe
VHF? Taxi
Landing
Nav
Strobe

*The plans show Pitot tube installation after the 9th rib, or in the same place as the tiedown and aileron bellcrank. It’s going to be cramped in there, so I might move the installation one bay further out. Or maybe two bays further out…I have the holes for it. (Stall warning will go one bay outboard of tiedown.)

Anyway, those are my plans for now, but I’m sure things might change. For one, I need to look more at the tiedown/pitot tube geometry. I think it will be too cluttered in the bellcrank bay, but any further outboard, and the pitot tube might be in the way of the tiedowns (low wing short airplane means tiedowns will be at a small angle.) I don’t want the tiedowns getting hung up in my expensive pitot tube.

1 hour.

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Finished Right Rear Spar

September 14, 2010

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So on the scale from “no help at all” to “girlfriend built the plane all by herself,” we made a few steps last night.

After dinner (thanks Mi Pueblo!), I convinced the lady friend to come outside and help me finish up the last few rivets on the right rear spar.

I talked her through going to the plans, looking at the rivet callout legend, and then putting the rivet in the appropriate holes, making sure to avoid the “rivet later” holes.

We were planning on having her actually squeeze the rivets, but the AN470AD4-6s (and -8s) were too much. She ended up holding the spar steady for me and helping with rivet layout. (See, I told you it was a small step toward “girlfriend built the plane all by herself.”)

I’m working towards being able to call from a business trip across the country and tell her to do something offhand like, “Hey honey. Can you hang the engine for me tonight while I’m away? Great. Thanks. Bye!”

Here's the plans shot for the reinforcement fork.

Of course, we were too busy being in love (with each other and the airplane) to take very many pictures, so you just get the end result. The main squeeze did a great job reaching all of these rivets (mostly due to the 4″ no-hole yoke).

Final rivets in the fork-only area. 38 rivets here.

Closeup of the fork and doubler plate together.

Final rivets in the doubler plate. 7 more rivets here.

Finished product.

0.5 hours (thanks, girlfriend), and 45 perfect rivets.

For those of you paying attention to the totals, that brings me to 175 hours (after 261 days) and 2409 rivets (of an estimated 20,000). Still a long way to go.

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Final Prep for Right Elevator

May 20, 2010

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Well, after deciding not to work out tonight (in favor of wine), I made it out to the garage pretty late for some final prep work before riveting the right elevator.

Tonight's build partner, 2004 Manyana (play on words) Crianza. A delicious tempranillo from Spain.

On with the building, you say? Fine.

One of the last real fabrication items I have left on the right elevator was enlarging the counterbalance skin dimples. To make a long story short, I don’t have #10 dimple dies, so I dimpled with #8, and then planned on using the AN507 screw head and a nut tightened down to enlarge the dimple enough for the screw to sit flush.

This did not work.

Okay, instead of waiting for a week for a $40 dimple die to arrive, let’s be creative.

Plan: matchdrill two holes in a block of wood, countersink the holes, then use a flush set to enlarge the dimples.

Here's my block of wood, later to be countersunk.

Well, I don’t really have any good pictures of my attempt, because that didn’t work either, and I was getting frustrated.

Finally, I told the girlfriend to come out and listen to me explain the problem. (I knew this would help me come up with a solution.)

Without even flinching. “Why don’t you use a bigger screw to make your dimple?”

my face = <deer in the headlights>

Of course! (Except I didn’t have a bigger countersunk crew, but it set me down the right path.)

This should work. (It's my punch set that came with my rivet gun.)

Setup recreated (I had a piece of tape on the skin to prevent marring.)

The hole on the left has been "enlarged." This worked great!

Okay, let’s move on. Next up, I needed to locally bevel the edges where the spar and tip rib are underneath the counterbalance rib (so the top skin doesn’t show the transition bulges. So I marked those, and also started thinking about how to attach these empennage tips. See the two undimpled holes to the right? Those are two (well, 4, two on top and two on bottom) tip attach points that will eventually be drilled, deburred, and dimpled. Might as well do it now so I don’t have to worry about deburring between riveted sheets.

Lining things up to wrap my head around this interface.

I flipped the pieces over and drilled them to #30.

The top two holes have been drilled and deburred, ready for dimpling.

After dimpling…this #6 screw fits pretty well. (Editorial note: I’m pretty locked in to attaching the elevator tips with screws. I know there is really no reason to take the tips off, but right now, I don’t want to commit to blind rivets.)

That #6 screw looks like it will fit pretty well.

Once the other side was done, I primed the interior (and taped off exterior) side of the counterbalance skin.

Priming. You can see the two #6 dimples at the top of the left side of the skin. (I'll do the rest later...the rest are all accessible in the future.)

While that dries…let’s devinyl!

Hooray for devinyling!

All done. (After using compressed air to blow the flaked primer off.)

Back to emp tip attachment, here are the #6 holes in the skin, dimpled the same way as the counterbalance skin.

Nice big dimples. (Whoa, I forgot to deburr that relief hole on the left there. Fixed after picture taken.)

Let’s get this thing clecoed together.

Those big dimples sit nicely in each other. Here you can see those two holes are the only holes that overlap.

Next, the manual has you rivet the following two holes (not accessible once the spar and tip ribs are in place).

Protected with tape, this rivets were set beautifully.

Without clecos, it's starting to look like an elevator.

Next, “loosely place” the counterbalance in the counterbalance skin and “partially” insert the screws.

The untrimmed (on purpose) counterweight in the counterbalance skin.

last, but not least, they have you insert the skeleton in the skin and cleco together.

Wuhoo! It really does look like an elevator!

Those screw heads are pretty flush. (They are not tight yet, so they'll sit a little better once I get them tightened down.)

A couple pictures of some of the interfaces.

Just behind the counterweight.

Trailing edge of the tip.

Inside corner of the counterbalance rib. (What's that stuff hanging from the top edge? I'll have to investigate later.)

Finally, the trailing edge of the inboard rib.

Ready to rivet!

One more shot.

1.5 hours, 4 flush rivets set.

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Right Elevator Stiffener Drilling and Dimpling

April 14, 2010

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Another fairly boring night with right elevator stiffeners, but the end is near (end of right elevator stiffeners, not the whole airplane), so I’ll keep plugging away.

My setup for drilling stiffeners. I used the cordless today so I wasn't making too much noise. I'm almost done with this side.

I matchdrilled every hole except for the last hole (closest to the trailing edge.) Some of these last holes are both pre-punched, and just need to be matchdrilled to final size, and some are missing the holes in the stiffeners. You have to use the skin to matchdrill the stiffener.

Down the right elevator.

I unclecoed most of the stiffeners and then re-clecoed the stiffeners (just at the ends) with the elevator off of the table so I can roll it over to drill.

Ready to flip over and matchdrill those last stiffener holes.

One picture of the last hole.

The hole at the end of the "3" is the one I need to matchdrill.

After that, I used a thick sharpie to trace the stiffeners to help with future devinyling. Then, I flipped the whole thing over to start on the other side. Same process, though.

About halfway done with this side.

Then, uncleco from the table to flip over and get the last hole.

Unclecoing from the last hole.

No big deal for you, but I marked all of the stiffeners correctly. The right elevator in the background is sitting upside-down (I just typed right-side-up, and had to change it. See, I’m still confused). Anyway, the ones on the table are on the top surface of the elevator, but the one in the foreground is marked the top (“Top, A”), but is actually the longest bottom stiffener.

This should be "BA" for "Bottom, A."

After finishing all of the stiffener drilling, I took them inside to deburr. After all of the deburring, I grabbed this shot of the placemat on the kitchen table. (Don’t tell the girlfriend. I got it cleaned up.)

Aluminum shavings galore after deburring. This is kind of a stupid picture, but I already uploaded it, so I'm not going to hold back.

After deburring, I rubbed down the surface that needed to be dimpled, (not the perpendicular surface, and I definitely didn’t do any edge-finishing).

Deburred and scuffed, ready for dimpling.

And I would like to draw your attention to the following three dimples. Don’t they look lovely?

Looks like a professional dimpled these holes.

It was the girlfriend!

Girlfriend dimpling. (She kept giggling after each one. And after each time I said "dimple." There may or may not have been red wine involved.)

Anyway, she made it about 8 dimples before getting “bored” (I think her hands hurt, too). Back outside, I found this little guy.

he's pretty small, but looks kind of scary.

No real identifying marks, but I’m sure someone will be able to help out.

Anyone have any ideas?

As if I hadn’t had enough drama for the night, Ginger came out, grabbed some wood, and took it inside to chew up all over our staircase landing. Here are some of the remnants.

It's better than her eating the window sills. Or the banister. Or our patio chairs. Or my soul.

Anyway, I spent a few more minutes with the Permagrit block rounding the edges of the stiffeners. Next up, edge-finishing with the scotchbrite wheel, scuffing, cleaning, and priming. Then, same dance with the skin and the backriveting!

An hour and a half. Boom shakalaka.

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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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LH skin dimpling, some HS riveting

January 9, 2010

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This morning, I snuck out into the garage and starting dimpling the left hand HS skin with my new (borrowed) c-frame.

After thinking about the setup and trying a few things, I quickly realized I wanted the female dimple die underneath and the male dimple die on top.

I set up the skin on 3 2x4s (I haven’t built a dimpling table yet because I wanted to see how I liked doing it) which was less than a 1/4″ above the female dimple die. Then I basically moved the c-frame around until the male dimple die was lined up (this way I don’t scratch the skin with a male dimple die while trying to locate the hole from underneath, like some builders do). Then I held the male dimple die down into the hole and…WHACK! Perfect dimple. I am far happier with these dimples than the pop-rivet dies. Keep in mind here, I am dimpling with the standard spring-back dies here, not the tank (deeper) dies.

Here's my setup for now. I like this because you move the c-frame, not the skin.

After finishing each row, I put a line of blue painters tape on the outside of the skin. I learned on the practice kit to protect whatever I didn’t want to scratch. The tape will come off just before riveting.

Blue tape on the outside of the skins. Hooray protection!

After I finished both sides, I scuffed up the internal lines, cleaned, then primed the inside of the left HS skin.

Here's the inside of the left skin, all suffed up, ready to prime.

While I waited for skins to dry, I riveted together HS-705, HS-702, and HS-704, but only the middle two holes. The rivets didn’t bend over, per se, but set a little crooked. (My fault for not keeping the squeezer steady.) I drilled them out perfectly, and then decided shooting them might be a better idea. After practicing with a piece of scrap for a minute, I actually ended up shooting these rivets. They look really good.

Shop head picture. Rivets 7 and 8.

Machined head picture. This just looks good.

This is not the order the directions has you rivet, but I was getting antsy to get some primed pieces together. Notice I didn’t slide in the HS-710 and HS-714 yet (still need to finish those), as you can set HS-404 to HS-702 to HS-405 without them. Then, it is off to run some errands.

When we got home from running some errands, my latest Avery tool order had arrived. Finally, a scotchbrite wheel! 6″x1″x1/2″ CP-7AM “Cut and Polish” Medium wheel. Also, I’ve heard some good things about the Permagrit line of products, so I picked myself up one of the 12″(?) ones. Fine on one side, coarse on the other, flat (I heard not to get the curved (convex) one.. Much better for making a straight edge than my regular file.

More tools!

First thing after mounting the scotchbrite wheel, I finished the edges of HS-710 and HS-714 with the wheel. So easy. I should have ordered the wheel at the beginning. (Serves me right for trying to piece together a toolkit instead of buy one all at once. I thought the scotchbrite wheel was a luxury. It is not.) Then I countersunk the holes in HS-710 and HS-714. I had done this before, but sized the countersinks perfectly for a AN426AD4- rivet. When you cleco the dimpled HS-702 front spar to either piece, the spar doesn’t sit flush, so you have to enlarge the countersinks.)

Enlarge countersinks. Check.

Then I finished surface prep, cleaned, and primed those two.

While waiting for the primer to dry, I clecoed HS-707 (leading edge “middle” rib) and HS-706 (tip rib) to the left skin to get in the mood for riveting. The girlfriend and puppies are taking a nap, so I’ll have to come back to this later, but I’m getting excited to start skin riveting.

HS-707 and HS-706 all clecoed to the left skin and such.

Anyway, I put in a few minutes of right HS skin deburring, scuffing, and dimpling before coming in for the day. (Notice I decided to scuff the interior of the right skin before dimpling? It’s easier to scuff the skin without all of the dimples getting in the way. It’s these little things that will save me time the second time around.)

Let’s see. 9am to 11am, 2pm to 4pm. 4 hours today.

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