Back to business

After a relaxing week of cruising around in the Caribbean, I've decided that there is such a thing as too much relaxation.



As odd as it sounds, it was almost a relief to get home and start getting back into my normal rhythms. Ask me how I feel about it tomorrow after my first day back to the paying job and you might get a very different answer, but for now I am enjoying getting reacquainted with my pets and my RV project.

Thinking back to when I set aside the tools last week, I remembered that I was getting ready to rivet the belly skin onto the fuselage center section. I didn't remember exactly how much there was left to do before the big riveting session. As it turns out, there was only a couple of hours of installing nutplates and clecoing stiffeners into place.

UPDATE UPDATE UPDATE
Skip ahead to page 28-06. DO STEP 1 BEFORE PUTTING ON THE BELLY SKIN!!


Here's why: http://www.schmetterlingaviation.com/2010/07/conniptions.html

I was pretty proud of myself when I got out to the hangar and found the required 20 nutplates to be already dimpled and ready to go. I was slightly less proud when I started looked for clecos to fix them into place for riveting and, for that matter, rivets to use to rivet them. Luckily it's only a couple of miles round trip to go back for more supplies.

Before I could even think about putting in the nutplates, I had to get the blue plastic off of the skin. That particular skin has been out in the hangar for a couple of months now, and the various weather conditions it has endured have caused it to form some kind of deep emotional bond with the protective plastic. It took a large PVC pipe to force the sticky blue stuff to part from the skin.



The nutplates went in easily enough. The next step was one that I remember causing a great deal of anguish back when I was building the tail cone: break both edges of the belly skin.

Piece of cake, now.



Then it was a simple matter to put the skin in place.



I started clecoing at the front corners, then went to the back corners.

The holes didn't line up. The holes weren't even close to lining up.

That, I'm here to tell you, caused a moment of extreme panic. Did I get a bulkhead on backwards? Is the skin upside down? Where are the plans - gotta see the plans - how could it be this far off??

It all looked right on the plans.

Huh.

Then I tried lifting the main center section up to see if maybe there was supposed to be some curvature to it.



That did the trick!

Whew!

I added another 2x4 to keep it up where it needs to be.



I clecoed and put reminder tape on the no-no areas that are called out on the plans to remain rivet free and clecoed all of the other areas. The last two steps before the big riveting job were to install two different types of stiffeners, one type under the skin and one type on the outside.





It's ready to be riveted!



It's going to have to wait a few days. I'm taking my handy little laptop out to Lancaster tomorrow or Wednesday to apply firmware updates to the Dynon boxes in an RV-12 being put through its final stages before inspection and first flight. That seems like it ought to be educational. The Schmettering CEO is coming for a visit on Thursday, so I'm thinking that I might save the riveting for him to assist with. It is, after all, one of the funnest jobs in the entire build. The air rivet gun never fails to impress.

Shop Closed - Gone Fishing

Well, not fishing. But the shop is going to be closed for a week while I pursue other pursuits, so to speak. I had hoped to get more done this week but between the paying job and other stuff that needed to be done on one side, and the impending deadline on the other, I find this YouTube visual metaphor to be quite apt:

The Shark

Two things about sharks: they have to keep moving, and they have cool gills. How cool? Cool enough that designers have been plagiarizing them for years and years.











They sure look good, don't they? Well, as it turns out they are quite functional too, and I don't mean just for sharks. Although if you ever asked a shark, I suspect he'd tell you that no one really needs them more than he does. The shark has a weakness, though: he has to keep moving to breath. And he has to keep breathing to grow. And he has to keep growing to get big enough to sink a boat out from under that twerp Richard Dreyfuss. Win-win, I figure.

Yes, you're right. This is another one of those long-winded, stretched-to-breaking metaphors. Rather than drag it out any further, here's the deal. I had to move the fuselage to the hangar. It was getting bigger and bigger and was in danger of being beached stuck in the basement. As it was, it was already too big to move in my Subaru. I had to enlist the aid of a slightly larger SUV.

Too slightly, as it turned out. It wouldn't fit in there either.

It had to ride on top.



What's that got to do with the aestheticism and functionality of shark gills, you ask? Is having to move the thing really a thick enough plank to support the weight of that overwrought simile?

Nope.

I have to stop here and share something. This is blasphemous and you may want to avert your eyes. As unpleasant as it is to say, I feel that my inherent honesty compels, neigh, requires that I confess that there are two parts of the RV-12 that I find to be absolutely hideously ugly: the wing tips and the shark gills.

The wing tips have unsightly gaps where the openings between the tabs on the flanges show through, but they are designed for function over beauty. They are (ostensibly) easier to build than messing around with fiberglass, and they have nice hand holds built into them to aid in carrying the wings around when they aren't attached to the rest of the plane. Ugly, but eminently functional.

The shark gills address another building issue. Where the front of the plane meets the back of the plane, there's one of those uncomfortable situations like the east side of a transcontinental railroad being a few feet north of the west side when they first meet in the center. With the RV-12, there's a section that would require a compound curved piece of metal. Rather than create an expensive and hard to produce piece, the designer(s) opted for some curved pieces that would attach together and work their way around the tough spot. I call them the shark gills.

For me, the shark gills have been of those iconic parts where I had seen them on a completed plane and thought "I'll rivet those in myself some day." It was right after thinking "Man, are those ever ugly!"

Today was that day.

I had to finish up a little bulkhead riveting first. Once I realized that I'd be moving to the hangar (Home of the Big Boy Power Air Riveter!) I went on a bit of a riveting strike. Why tear out my tendons using the manual rivet puller when I was going to have the power of compressed air to do my bidding? That said, there were rivets inside of flanges that I'd have to deal with. I've been doing those manually. I figured I'd burn that bridge when I got to it. For now, it was full steam ahead on the bulkhead.



Have I mentioned how easily I get spoiled by power tools? I'll spend an order of magnitude more time and effort trying to force a power tool to do the job than it would have taken to just knuckle down and do it manually. Which is how I ended up pulling the inside flange rivets with the air puller.



Oddly enough, it worked pretty well. Right up until it didn't, anyway.



Just as I did with the manual puller, I used the little metal wedge to get the rivet puller in good contact with the rivet. Unlike with the manual puller, if the little wedge gets a little crooked while I'm pulling, it gets, well, wedged pretty tightly in a bad place. It was quite a chore to get that thing back out of there.

The next step was to put in a slew of plastic bushings. They just snap right into the holes and are very simple to install, but I found that I had to lay the plans on top of the fuselage to figure out exactly where each was to go.



And, at long last, the shark gills!

First, cleco them into place.



It goes something like this:

(You might have to press the play button for the full effect)


And ends like this:



The longerons are the next iconic step. And I hear they are no fun at all.

The increased dating pool

I didn't go to work today, at least in the normal sense. Rather than my thirty-five minute semicircumnavigation of the city followed by nine hours of mental labor sitting in front of a admittedly quite nice 24" LCD monitor, I drove 10 minutes to a local distribution center where I was to endure eight hours of Diversity Training. Those amongst you with experience in the ways of Corporate America are no doubt wondering what my infraction was that warranted such harsh punishment, but I went voluntarily. Well, it was mandatory training, but I volunteered to attend at this particular location just for the easy commute that was in it.

It's not that I find no value in these classes; some of them are quite valuable. Others, not so much. The corporate CYA classes, for example, are shallow, facile time-wasters that serve no purpose other than allowing the company to wash their hands of you and your behavior should your actions ever result in a lawsuit.

"Hey, we trained him. Don't blame us!"

This was not one of those classes. The knowledge imparted was both contemporaneously pertinent and well presented. The class did feature one of the things I hate the most about these kinds of seminars, though. We had to separate into sub-groups for "an activity." The only thing worse is role playing. In this case, there were three groups separated based on our childhood environments. One was rural, one was urban, and mine was suburban. We were instructed to write on the large easel-mounted paper some of the defining traits of our environment. For us suburbanites, we came up with:

- Safe
- Quiet
- Lawns to mow
- Neighborly
- Etc. You get the picture.

We were then instructed to flip the paper we were writing on. Our next sheet said Rural. We were to write our perceptions about what it would have been like to grow up in a rural area. We came up with:

- Boring.
- Wide open spaces.
- Lot's of animals and smells. (Hey, have you ever smelled a manure spreader on a hot August day?)
- Early morning chores.
- Dangerous. (That one was submitted by an agoraphobic co-worker that watched the movie Deliverance at an impressionable age)

The fun part was when we had to read our lists to the entire class. We suburbanites got a chuckle when the urban kids listed 'Upper Class' and 'better stuff' under the Suburban category.

When that was done, we flipped our charts again. The new headings were 'Straight', 'Gay', and 'Bi'. Our category was 'Bi'. Assuming that we would be tossing out our perceptions regarding those lifestyles, I suggested that our number one item be "More Options."

In retrospect I wish I had worded that "Much larger dating pool."

It was after we had recorded our perception for all to see that we noticed that the rest of the class was not participating. The reason became clear: the intent was not for us to actually write or say anything; the facilitator (what normal people call the 'teacher') had been trying to make a point. The point was that we are perfectly willing to talk about mundane cultural differences, but are far more squeamish about discussing more personal or potentially controversial traits.

In theory, anyway. I didn't get that memo. I was perfectly will to talk about it.

So, you're wondering why I share this story, aren't you? Well, the fact of the matter was that I leapt into action without waiting for the full set of instructions. The interesting thing is that I did exactly the same thing last night.

Consider this set of instructions:



I read through that paragraph at least five times. My sticking point was that I was being instructed to install nutplates to only the F-1225-R Seat Floor, which kind of left the fate of the F-1225-L seat floor up in the air. Now I figure that if Van's doesn't specifically tell me to do something, well, it's not my place to question why. There is inevitably a step later that answers that question. The problem is, if I was going to do both floors I'd prefer to do that all at once so I wouldn't have to reconfigure the rivet squeezer from 'dimple the nutplates' mode to 'squeeze the rivets' mode. Resigning myself to the fact that I'd end up doing the left side sometime in the future, I went ahead and did the right. I dimpled the nutplates, changed the rivet dies and the gap between them for the AN426AD3-3.5 rivets, and finished installing the nutplates.

By this time, 99% of you are screaming "HEY! It says RIGHT THERE to repeat this step for the left side!"

In half a dozen times reading through that paragraph, I swear that I never saw that sentence.

There's a lesson in there. It ought to be a lesson that sinks in now. After all, I've learned it twice in as many days.

A movable part!

I installed a movable part tonight, and what's more it was a part of the actual control system.

Most of my nights in the shop start out with something mundane or difficult, or both. That's because when I was faced with something of that nature the night before, I decided that it would be a good time to stop. Tonight is was nutplates. Again. They weren't too bad, though, since they ran along the edges of the floor boards I had riveted in last night and were therefore easily accessible. Well, mostly. There were a couple that required reaching up behind the bulkhead to get into position.



There were five to do on each side. That's a total of ten for anyone keeping score at home. There were three of the type of soft blind rivets that have been giving me fits on each side, but I was able to pull all six without having a single one break off way up inside the rivet puller as has been happening recently. The trick seems to be to squeeze just a little, release the squeezer and reposition it at the bottom of the nail, repeat, repeat, repeat. It's when I try to pull the nail in one big squeeze that I have the problem with them breaking off up inside the puller.

Here the are, all in a row:



Finally it was time to thread the control column through the lightening holes and into position. Well, first I had to final drill all of the holes in the tabs that the mounting bolts pass through to remove the powder coat, but that was more or less easy. The 'less' was because there were holes that were too tight up against the control column for the drill to fit easily, but I managed.

Speaking of tight fits, it took quite a bit of jiggling and wiggling and wrangling and tangling to get the column through all of the holes. It was almost like a puzzle - turn it this way to get through this hole, and that way to get through the next one...

It took a lot longer than you would think.



Here it is, all snug in position:



There are just a couple of small bolts that hold it into place, but each bolt has a collection of five washers that act as spacers. The order goes bolt head - flange - washer - washer - bearing - washer - washer - flange - washer - lock nut.

Four out of the five washers are a pain to get into place. The plans suggested using a tab of tape on the washers, which actually worked pretty well once I figured out what they meant.



The first bolt took 15 or 20 minutes (and a half dozen dropped washers) to get in. The second went a little faster, but not much. Both were torqued into place.



Unfortunately, the first bolt was just for practice. As I was making my last quality assurance check, I realized that I had made a mistake.



I installed that one bolt head - washer - flange instead of bolt head - flange - etc.

The one easy washer was on the wrong side of the arrangement. The hole thing had to be removed and done over.

That kind of thing seems to be getting to be a habit.

Old Yeller pulls through!

Making a mistake late in the evening when I'm tired from a long day of work has pretty much the same effect as eating a large pepperoni and coffee bean pizza just before bed: I sleep, but not the restful, rejuvenating kind. It's a shallow sleep, easily disturbed by the puppy rolling over in his crate or the cat losing what must have been three separate meals on the bedroom carpet. It's a sleep also punctuated by bizarre and disturbing dreams that magnify and amplify the stresses of the day into what seem to be insurmountable obstacles. In the early dawn's light, though, things return to their normal scope. Things like doublers on the wrong side of the bulkhead no longer carry the import that they did in the middle of the night; they are seen for what they are: an hour of backtracking before tackling the job again.

Which I did tonight. Job number one was to craft a tool that would aid in removing the LP4-3 rivets. Those still have a piece of the "nail" in them and that can cause problems when trying to drill them out. The bit senses the harder metal of the bail and, much like a good running back, just goes around it. That's not a good thing since the "around" is comprised of important material that we don't want to cut away. To punch the nail out, I borrowed an idea from a $20 tool I saw recently. I ground down the tip of a $5 Harbor Freight center punch to that it would fit into the center hole of the rivet. Just a punch or two was enough to punch out the nail.



It pops them out with enough force that I could hear some of them bouncing against the far basement wall. I'm going to be finding those for years! Once the nail is out, the drill bit walks right down the hole in the rivet and pops the head off in no time at all. Conveniently, the rivet heads roll up the bit for later disposal.



The solid rivets were much more difficult, although I did find that my new rivet removing punch worked just as well at pushing the body and shop head of the solid rivets out of the hole once the top of the rivet had been drilled off.

Everything was then reassembled and we were back to where we started, except with the doublers on the other side of the bulkhead.



I had enough time left to take the next step. That was the riveting in place a couple of the floors. These particular floors will be under the seat cushions when the plane is done. They have a pretty sharp bend on one of the flanges, and unfortunately it requires dimpling for a nutplate and an eventual rivet. That was a bit tricky and I eventually had to resign myself to the fact that the flange was going to get a wee bit bent out of shape from forcing the rivet squeezer (equipped with dimple dies) in there to get the job done.



The floors were easy to rivet on, although I did have a situation where one of the LP3-4 rivets pulled halfway out of the hole on the first squeeze and had to be drilled out. Having perfected the job of drilling out blind rivets only an hour before, I didn't even breath a sigh. Took it in stride, did I.



Tomorrow is a big day! The first of the control pieces goes in. It's the column that ties the two control sticks together. This is when it will really start to feel like an airplane rather than a ghastly ugly modern art sculpture.

Books about dogs

Do you know what the #1 rule is about any novel involving a dog?

Don't read the last chapter.

From Old Yeller to Marley & Me, they're all the same. They end in tears.

Remember that. There's a reason I mention it.

The night started out with 17 nutplates, but they went quickly since they were going on the other side of countersunk holes. That means they didn't need to be dimpled. Thirteen of them were aligned along an edge, so it would be easy to get at the rivets with the squeezer. The other four used blind rivets. That used to be good news, but I've been having trouble with the butter-soft blind rivets breaking off in the puller.

So, the easy thirteen first:





Then the four with the finicky blind rivets, approached with a gentle touch and increased diligence in keeping any side angle off of the rivet puller.





Only one stand-out. Could have been worse.

The last step before mounting the bulkhead onto the rest of the fuselage center assembly was the mounting of a couple of doublers. That involved a relatively large collection of LP4-3 blind rivets and AN470 4-4s that I'd have to squeeze. The -4s were, as always, a good workout.



That was enough for the night, but I couldn't resist doing the next step which was to finally cleco the bulkhead to the front of the fuselage section in preparation for riveting. I carefully flagged all of the holes that were to remain open.







As I was taking a final look at the plans to make sure that I had all of the correct holes flagged, something caught my eye. See if you can tell what it was:





Did you get it? Did you see that the doublers that I riveted in are on the wrong side of the bulkhead?

Do you remember that stuff about sad endings?

Yeah, it's like that.

Drilling those rivets out is going to be an onerous chore, and I'm also going to have to order a new bag of them as I won't have enough to replace them with the few that I have left.

There is some very, very slight chance that I could leave those doublers where they are, but I'd have to call Van's and ask. I'm sure Van's has heard just about every sad tale of builder's mistakes under the sun by now, but this one is bound to go to the top of their "How in the world could anyone do that??" list. I can't decide whether I want to suffer the embarrassment on the very slim chance that it doesn't make any difference where those doublers are.

Poor, poor Old Yeller.

Another break?

Yep, I took another night off. The weather was superb and I decided to take advantage of it to go flying.

I was back in the shop tonight, though, albeit for less than an hour and a half. That was just long enough to finish up page 21-11 before I developed a raging headache. As far as getting a lot accomplished, it didn't really seem like a lot got done. There was plenty of activity, though.

I squeezed in a passel of nice, thick #4 rivets which went as well as can be expected. Those were the last rivets needed to secure the doublers that I started installing last time. Then there were four #3 rivets on each of the doublers that went into their respective flanges, presumably to hold them together under duress. The manual said that it would be okay to use two flat dies if I wanted to, but I couldn't figure out why I might want to do that. Van's was acting like they were doing me some kind of favor and I felt kind of embarrassed that I was too provincially gauche to see the value of their beneficence.



Being #3 rivets, they squeezed in as easily as crushing a cooked noodle.

The other parts that I had assembled last time (control column bearings, I think) were then riveted to the bulkhead with blind rivets, but simultaneously there were some of the world's angriest nutplates to deal with. These are the nutplates that have the screw hole on one end and the two rivet holes right next to each other on a tab.

I call them angry because by the very nature of their design they make themselves very difficult to install. Typical of our contemporary society, I ascribe malice to anything or anyone that causes me inconvenience. In the case of these nutplates, the inconvenience comes from not being able to use clecos to hold them in place for riveting. The rivet holes are so close together that the cleco blocks access to the rivet squeezer.

Maliciously petulant jerks.



The only way to hold them in is to temporarily install a screw. That holds the screw hole in place, but it does nothing to hold the nutplate flush up against the aluminum like a cleco would. It ends up being a three hand job to hold the nutplate, get the rivet into place, and use the squeezer.

Sadly, I still only have two hands. It takes a contortionistic ballet of hands and tools to get it done, and it is by no means enjoyable.

After those were finally in, there was the simple matter of eight more nutplates that go on the flanges of the bearing plates. Those take flush mount #3 rivets to mount, but I couldn't help noticing that the holes weren't countersunk. That, of course, made no sense. I went back a few paragraphs in the plans and found the step that I had missed. I made amends with a quick countersinking operation and installed the eight nutplates. That brought me to the end of the page at right around the end of my patience with the headache, so I called it a night.

Well, almost. I still needed to vacuum up the metal shavings on the work bench and the bulkhead was in the way, so I temporarily clecoed it into its place on the fuselage.

A brief break

For various and sundry reasons, and none of them truly adequate, I haven't been flying the RV-6 as much as I ought. Last night was clear, calm, and compellingly conducive to completing a competency-enhancing collection of quality practice landings, so rather than absent myself to the basement shop to labor over cold, cantankerous aluminum, I carried myself to the airport for some flying.

It's good that I did, if my first landing was any indication. Had I gone any longer and let my skills atrophy any further, I might actually have literally left parts of the airplane on the runway rather just thinking that I might have. Fearing the obvious threat of permanent damage, the plane behaved much better for the remainder of the evening.

I was back at it tonight, but only briefly. The sum total of tonight's efforts was getting a set of doublers partially attached to the bulkhead that I've been working on. These are moderately tricky in that they use a few different rivets and, as is getting to be the norm, have collections of holes that are to be kept rivet free.

First there were some #4s to be squeezed:





Once squeezed, the #4 rivets get covered up with the doublers. That was kind of weird - typically any rivet that will have something on top of it is a flush rivet, but these fit up into the "folds" of the two doubler halves:



These doublers provide the strength required to hold the second set of wing spar tabs. Obviously there's going to be quite a load transferred from the wing roots through to the fuselage from these tabs, judging from the dense packing of holes that will be filled with #4 solid rivets.

I pulled the dozen blind rivets in each set of doublers but left the #4s for another day.

Squeezing all of those is going to be fun. Maybe I'll go flying again...

I have seen my future....

... and it is (prepare yourself!) nutplates. Shocking!

After retrieving my Uni-bits from the hangar, I was ready to start preparing YAB. What's a YAB? Oh, that's "Yet Another Bulkhead." I left out a letter or two in the interest of brevity.

Twenty-three nutplates. Two countersunk holes each. Plus another six #30 holes to be countersunk with the 120° bit. That means CS-4 blind rivets instead of squeezed #4 rivets sometime in my future, so there is that. But it still added up to fifty-two holes to be countersunk.



I shouldn't sound so down about it - I actually like countersinking. The micro-countersink thingy has a solid feeling of precision mixed with get-outta-my-way brute force that I somehow find enjoyable to use. But still... fifty-two! That naturally left a lot of metal shavings scattered all over the work bench, so I somewhat absently lit up the powerful shop-vac to apply some housekeeper's suction to the mess. As I was vacuuming around, I heard and felt a thunk in the hose and saw something larger than a metal shaving go flying up the nozzle. I thought it must have been one of the little lengths of cut up wooden paint stirring sticks that I keep around to support thin aluminum when I cut it with the band saw. I was thinking of just letting it go at that, but thought better of it and opened the vac to see what I had netted.



Oh. A little plastic bag filled with the three not-currently-in-use countersink bits. I would have never found those!

Retrieved:



The countersinking had taken up most of the hour that I had to spend in the shop, and I hadn't even gotten to the part where I needed to use the Uni-bit! I didn't figure that part would take too long, though. I don't like using the Uni-bit for precisely the reason that I thought the job would go quickly: they make a big hole very quickly. It actually takes quite a bit (heh) of caution to avoid going a step too far and making the hole too big. The big hole on the left would have to be finished by removing the small amount of metal at the bottom of the hole. That would be done with cutters and files.



Starting with the big hole:



Even though the larger bit on the right has a 7/16" step, I thought it would be safer to use the more tapered bit on the left for the 7/16" holes because it would give me a wider step between holes, hopefully providing the buffer I'd need to keep from over-drilling the holes. The big bit worked fine on the 3/4" hole since that was the maximum diameter of the bit anyway.





I put the filing off for last. The plans suggested a round file for that. I ought to look into getting one. I just used my little jeweler's files - that took awhile!



I finished it up just as my hour expired.