Saturday, June 30, 2012

Stress, Fun, and a Modicum of Intense Frustration

It has been a week of endpoints. Highs, lows, and very little in between. It started out on a low, as we all know, as I found myself in a pitched battle with the recalcitrant fuel tank. I had a floating nutplate on order and high hopes that it would resolve the problem that I had been having with the inboard tank mounting frangible bolt. In fact, I had high hopes in a number of areas, but all were to come to nothing more but abject dejection.

Still, the early week weather was extraordinarily pleasant, even if the weather prognosticators were promising temperatures exceeding 100 degrees by mid-week. And as it turns out, they were as good as their word for better or worse. With sufficient warning having been given, I decided I'd try to get a promised RV-6 ride out of the way before the weather became prohibitively hot. There was also the risk that the plane might not be available for such things for long; I had an interested buyer that was going to come visit on Saturday - this one seemed to be a strong prospect. This was one of the high hope areas, if not the high hope area. The floating nutplate paled in comparison.

The ride was quite enjoyable - Penny has recently started working on getting her own license and seems to have been bitten pretty hard by the flying bug. She was quite enthusiastic about riding in the RV-6 and even showed a lot of interest in the RV-12 project. I picked her up over at MadCo since she lives near there, and because I wanted to buy some gas in order to have plenty available for Saturday in case the prospective buyer wanted (and who wouldn't??) a test flight.

The evening was perfect for flying and she had no trouble at all adjusting to the relatively light controls of the RV. I offered her the opportunity to ride through some more advanced air work and she was all in favor, although she did warn me that if she got a little nervous she might reach over and grab my leg. That, despite whatever her intentions may have been, was not what I would call a disincentive!

We did some chandelles, steep banks, and a few other maneuvers for awhile and only once did she show a little trepidation (despite whatever my intentions were) in the manner she had warned be about. All in all, I'd say she enjoyed the ride quite a bit.

The heat wave hit right on schedule, so any more flying or work on the plane was deferred until such time as the ambient temps get down to something more reasonable or, at least, survivable. With my confidence in selling the plane at an all-time high, I decided I might as well get serious about figuring out what I want to buy to replace my poor little Miata. You may recall that I was considering a new Mustang convertible, and I might have mentioned that I had also tempted myself with a new, retractable hard top Miata while test driving a Miata 2 with Co-pilot Egg.

On something of a whim, I decided that I'd take a look at higher-end used cars. With the kind of miles that I put on a car (20,000+ annually), I'm not sure that it makes a lot of sense to buy a brand new car and depreciate it on such an accelerated schedule. One of the first things I looked for was a BMW Z4. I drove one a few years ago and I remember liking it, so I checked around on the web and found a 2007 iteration at a dealership close by.

It was close to work, so I was able to squeeze in a quick test drive on my lunch hour. Unfortunately, it was pretty beat up. With only 54,000 miles on it, you might expect it to have a little cosmetic rash, but it should still drive okay. This one didn't. It had a shimmy in the steering, the brakes pulled to the right, and the shifting of the automatic transmission (I know, but it's required) felt awful.

As I was backing out of my parking spot at the office that very day, my eye was drawn to a fine looking roadster that said SLK 280 on the back. It looked mighty expensive, but no more so than the BMW. The internet makes it fall-down easy to find out about things like that these days and I always say, it's free to look. That's how I found this little gem at a dealership up on the north end of town.

Sold brand new in 2007 to a guy that only put 14,500 miles on it. According to the dealer, he only drove it to church on Sundays he bought it as a third car, but when his two kids got old enough to need cars of their own he traded it in on two brand new Subarus for them. He's a car salesman, of course, and I have no reason to believe that story, but nor do I have any reason to not believe it, especially since the facts of the matter were easily verified by CarFax.

I decided that it was worth a test drive and Egg, always keen on riding in something fancy and luxurious, agreed to join me.

What an amazing car! Those little slots in the headrests? Those are call 'air scarves' - they blow warm air on the back of you neck on chilly, top-down drives. The seat leather, made from the skin of pre-pubescent calves that had been given Shiatsu massage every day of their tragically short lives, was hand-stitched by destitute leprechauns who has lost their pots of gold after the dot-com bubble burst. The polished wood that made up 80% of the steering wheel was harvested by Baka Pygmies who had to stand on each others shoulders six high to reach the finest pieces of the trees, then crafted into a perfectly round circle by retired Norwegian violin designers.

Note: two out of three of the above statements are complete fabrications, and the third only sounds that way. You figure out which is which.

I think I have found my car. Not this one, more than likely, which is a shame, because I can't get the car unless 1) I sell the RV-6, or 2) I forego the pending purchase of avionics for the RV-12. The latter is out of the question, and the former was dependent on the Saturday buyer. But, like I said to the sales dude when he tried to pressure me with "this one won't last long," I'm pretty sure they made plenty more.

And as to the Saturday prospect? He stood me up. He had seemed very interested, and for all of the right reasons, so I was surprised by that.

And my high hopes? Dashed.

That, I have to confess, really wrecked my day. Yet another crushing disappointment to end a week of many. It could be worse, though. Many parts of the city, including Pete's neighborhood, are without power after a ripping big storm blew through last night. 95 degrees and no air conditioning. Ugh.

It could be even worse than that, even. I wouldn't want to be this guy either. He's standing there with his phone trying to figure who in the world you call to handle something like this:

I saw that on my way over to the airport this morning.

I was headed up there to install the new floating nut plate, which naturally required the drilling out of the nutplate rivets for what must be the fourth time.

And squeezing in the new nutplate. With high hopes, mind you.

Which were dashed. The bolt still wouldn't go it. Out came the rivets. For the fifth time.

Then I took a break to think about things. Fortunately, there is yet another B-17 selling rides at Bolton today. This is something of an annual occurrence. This particular B-17 is one of the half dozen or so that pretend to be The Memphis Belle.

Once back from watching the B-17, I did what I should have done in the first place. I decided to see whether or not a nutplate is really required in this case - any old locknut seemed like it would work just as well.

Which turned out to be quite true.

So there is that going for me anyway.

Monday, June 25, 2012

The Frikkin' Fuel Tank Fitting Fiasco

Van's Builder Assistance line opens at 10am Eastern time.

I started dialing at 9:57. I have no evidence to back up this assertion, but I believe first thing Monday is likely to be one of their busier times. I mean, how much airplane building goes on over an early summer weekend do you figure? Me, I figure it's a hella lot, and I wanted to be first in line.

At 10:01 I was on the horn with a very pleasant (and not at all condescending) Builder Assistant named Spencer. Keep in mind that 10am Monday morning to me is 7am Monday morning to a Van's employee (they're located in Oregon) and I was probably the first caller of the day for Spencer, so it took a little doing to try to paint a picture of my problem using only words. We all know that it takes a thousand words to stand in lieu of a picture, and both Spencer and I were pretty tired of the effort by word seventy-five.

"Hmmm," he said, "I might need some pictures."

This being my second rodeo, I already had an email window open and ready to send, the four most pertinent pictures already attached. All I needed was his email address. Even though we had only been on the phone for a couple of minutes, I got the feeling that there was no time to waste on his part, and what with me sitting there at my desk getting paid by an overly trusting employer, I wasn't keen on wasting a lot of time either while Spencer tried to sift my email out of the hundreds sitting in their shared inbox. He promised to retrieve the email and get back to me with an answer later.

Which he did:


After looking at your pictures and talking it over with one of the other guys we think your best option is to enlarge the hole in the tank attach bracket. If you take the nut plate off and enlarge the hole to accept the bolt you should be able to rotate the nut plate and drill new holes to attach it.


Concurrent with my help request from Van's, I had also posted as message on the peer-level Vans Air Force forum. I had also received a very helpful answer there:

I don't know if this is similar to your problem or not, but when recently doing the tank bracket modification on the Teen Flight RV-12 we had a bolt alignment problem.

Because of bend tolerances, the bolt hole in the bracket added to the left (inboard) side of the tank didn't align with the bolt hole in the lateral mounting plate on the tank. This made the bolt unable to be inserted when it came through the 1/4 inch thick center section C channel. It wasn't discovered until the tank was ready to be reinstalled.

We resolved it by removing the nut plate and then match drilling the #12 hole in the thinner bracket using the heavier mounting plate. This ovaled the hole in the bracket very slightly but none of the original design strength was lost because the hole in the mounting plate was undisturbed. A 10-32 floating nut plate was then installed in place of the original K1000, to allow for the slight offset in the nut plate position. The bolt went in easily at reassembly.

While this was very similar to my problem, I believe it was to a lesser degree. The suggested resolution was very similar, though, and had the additional suggestion of using a floating net plate. A floating nut plate is more forgiving of small misalignment issues because, as suggested by the name, there is actually a nut in it housed in a loose-fitting cage that allows it to, well.... float around a little bit.

Eh, I might as well save the other 960 words and show you a picture:

Naturally, I don't keep a collection of variously sized floating nut plates lying around, so I hoped that I wouldn't actually need one. After all, I would be match drilling the new hole and we all know how precise I am when it comes to match drilling....

That would come later, though. First I would have to remove the existing K1000-3 non-floating nut plate. This would be the third time drilling out one of the rivets in this particular nut plate. The first time was when I had to remove it for the Service Bulletin, and the second time was when I had to re-do the rivet after performing the Service Bulletin because I had accidentally left the flush head sitting proud when I squeezed it in. A flush head that doesn't sit flush pretty much defeats the design goal that drove the decision to use a flush head rivet in the first place, after all.  I had to fix that.

Why does it matter that the rivet had been drilled out twice already? Well, because there are only so many times that you can molest a rivet hole without ruining it.

With the nut plate removed, I could place the tank into the airplane and do the match drilling. Something was concerning me, though: would I be able to get a drill down into the center section?


I could have removed the wings to get those spars out of the way, but I would still have had the same problem, albeit to a lesser degree. It would still have been a little bit out of alignment, and just a little bit out of alignment is like being just a little bit pregnant.

I tried a different tack. I smeared some of the bright orange Torque Seal (which is really fingernail polish dolled up with a name that allows for a 500% price mark-up) on the end of the drill bit, then used that to mark the hole location on the tank.

I was reasonably sure that this would never, ever work, but I was wrong; the bolt fit in pretty well.

I screwed the nut plate in temporarily and marked its location with a Sharpie. All that was left to do was match drill the new rivet hole (after determining that only one new hole would be needed), but that presented a problem. There was no way to get a drill bit to it.

I had to put the nut plate on the other side and do the best I could at getting it in the correct position.

Here it is riveted in. Ugly, no? I suspect that my fuel tank installation is destined to be slightly more frangible than most.

Not just ugly, though. It also doesn't work. I got the nut plate alignment off by a minuscule amount, but it is just enough to make it very, very difficult to get the bolt in. Forcing a fit into a nut plate is a bad idea, generally, because if you ruin the nut plate it will be very difficult to replace. That's a somewhat obvious observation, I suppose, given that a nut plate is usually used for situations where the location is not accessible. This case is a little different in that I could choose to forego the use of a nut plate entirely and just use a lock nut, but what I'm going to do instead is order a floating nut plate, just like I should have done in the first place. That's okay, though, since I also need to replace the K1000-3 that I purloined from another part of the kit.

It's not like I have those lying around either, you know.

UPDATE: This appeared on the support forum after I shared my hypothesis that the center section must have been incorrectly drilled by Van's:

Your assumption is correct. The center section is drilled incorrectly. I measured mine and the dimension is the same as your tank bracket.

44.5 cm and the hole in the center section appears to be centered between the rivets.
So that's that. At least it wasn't something I did wrong, unless this is some form of Karmic retribution in which case, well, mea culpa.

The only tangible result of this validation is that I will forget the idea of ordering a new tank bracket to replace the one I've made such an unattractive mess of - it would require the same fix and it would more than likely end up being just as ugly.

Sunday, June 24, 2012


Following my prediction that we would "enjoy" a linear progression of ever-higher temperatures, a prediction based on the uncharacteristically mild winter we had, we had an August heat wave in June. When the temps are 90+, it becomes difficult to opt for a few hours in the temperature accentuating hangar (it makes hot days hotter and cold days colder) over spending an evening at home basking in more temperate, albeit artificial, conditions.

So after spending a week in air conditioned bliss, why is the subject of this post "Sweating?"

I'll get to that.

And to be fair, it was easy to opt to stay at home rather than work on the airplane because I had a part on order. As you may recall, I was working on the cable that will open and close the door that blocks heat from the aft side of the engine radiator from pouring into the cockpit. Cold in the winter? Pull the cable, open the door, get warm(er). Hot? Push the cable, close the door.

I had gotten to the point where I needed a rod bearing, but I couldn't find it. There was a bag that was supposed to have four of them in it, but they were all gone, probably having been used on other parts of the plane. They're cheap and I needed to order some other stuff from Van's anyway, so I ordered one on Sunday afternoon.

It finally arrived on Friday.

The first order of business on Saturday morning, then, was to use the newly procured part to finish that cable. First step: screw the rod bearing as far as it will go into the metal tube that will support it. Then tighten the jam nut hard up against it.

Jam nut? I couldn't find any of those either!

Pete: "Have you checked in the engine kit parts?"

Me: "Of course not. I'm working on the Finish Kit - why would it be in the Eng.... oh, yeah, here it as. And here's the rod bearing, too."

An ignominious beginning.

With the parts in hand, I did the measuring and bending of the control wire shown below. When that's done, the hooped end of the wire gets shoved up into the metal tube that holds the fully jammed in rod bearing. Then a cotter pin gets shoved through a hole in the tube and through the hoop in the wire.

I'm nothing if not pessimistic, and I had dire concerns over whether I'd be able to get that hoop into the tube far enough to get the cotter pin to fit through. Sure enough, I got it to where I could see the hoop through the hole in the side of the tube, but I just couldn't get the hoop to move the 1/32" further in that it would need to go to get the pin through it. I tried sticking an awl into the hole to force the wire further into the tube. No go. I tried pushing while swearing. I tried swearing while pushing. I even tried swearing before, during, and after pushing.

No good.

I am beginning to lose my faith in the power of swearing.

The problem turned out to be my slavish devotion to the instructions. Threading the rod bearing all the way into the tube as far as it would go had positioned it such that there was no room for the wire to go.

I had to let it out a few threads.

The cushion clamps that hold the cable housing in place are somewhat loosely mounted on the engine mounts (I don't know why - using the bolts called out by Van's, there's still a little looseness once the bolts are as tight as they can get), so a piece of safety wire is specified as a way to keep the cable housing from slipping.

Meanwhile, Pete worked on the tail cone.

Having finished the heater cable, I started on mounting the oil cooler. The plans called for machine countersinks on the inside face of one of the parts of the holder for the radiator. It was pretty close in there and the only way I could get a counter sink bit in place was to use my little hand drill. I was quite proud of having come up with such an elegant solution.

There were also a couple of doublers that surround the holes that the line fittings will mount to. Those too were dimpled to be flush on the inside.

And even more countersinking.

Then it all gets riveted together. But wait! What happened to my cleverly countersunk cavities? Crap! I countersunk the wrong part!

I didn't want to countersink this part too, thinking that a whole lot more material than planned on by the ultra-sophisticated computers at Van's had calculated as prudent would be removed by double cutting and that might not be a good thing. Instead, I dimpled the second part. It's not uncommon to dimple a thinner piece of metal where it joins with a thicker, countersunk part, so this felt almost natural.

A line of RTV gets run down the corners of the flanges just prior to putting in the radiator.

Van's suggests blocking off the oil fittings once they're installed to keep from getting dust and stuff into the system. The masking tape wasn't sticking very well, so I helped it out with tie wraps. I tend to the overkill, now and then.

Soon thereafter, it was determined that I had missed squeezing in a couple of rivets. Naturally they were rivets located in a spot that was now impossible to get to with the squeezer, what with the radiator oil fittings in the way. And there was no way I was cutting off those tie wraps!

Out came Gucci, my bright red rivet gun.

Pete had finished up the tail cone by that time, at least to the degree where the stabilator needs to be re-installed. Not being overly keen on that idea, I decided to work on the fuel tank instead. Even through I bought the tank already built, there's still some work to do to get it installed. First, the plans say to attach the fill tub with a big rubber hose and some hose clamps. And oh, by the way: leave a 1/8" gap between the fill tube and the fitting on top of the tank.

The rubber hose is, of course, slightly more than 100% opaque and there was no way to see any gap at all, much less a 1/8" . To solve for that, I marked the location on the side of the tube where it was flush against the hidden edge of the other fitting, then just moved the mark up 1/8".


And then the tank gets put into the airplane for the first time. And that went.....


Note the difference between where the bolt thinks the nutplate should be and where the nutplate actually is. It is a not insignificant difference!

This is when I started to sweat. Both set of holes (those in the central spine that the bolts pass through and those in the front of the fuel tank) were drilled by Van's. There is simply no way that I could have screwed this up; something is horribly, horribly wrong. There can be no easy fix for this.

Yeah, I started to sweat.

Meanwhile, Pete calmly whittled away on the cooling duct.

I tried over and over to get the tank to fit, but I just kept coming back to the same conclusion: something is horribly, horribly wrong. I'm going to have to call Van's tech support. That didn't go well the last time I had to do it; the condescending attitude of the support person I talked to had me steamed for days. In an attempt to mitigate the "you must be a complete idiot; we could never do anything that horribly, horribly wrong" attitude, I would have to gather evidence.

That turned out to be both easy to do and a strong conformation of the horrible, horrible problem.

This is the left (looking at the front of the tank) hole:

Here is the right hole. It's just a little more than 44.5cm from the front hole.

This is the right hole (looking aft) on the center section:

Right around 44.2cm. That's not good! It's .3cm to far to the left!

Here's another view of the right hole. If, as in the drawings in the manual, the hole is supposed to be centered between the adjacent rivets, well, you can see where the problem is.

It's that damn Metric system!

So, what do you want to bet that hole would be centered between the rivets if it was .3cm to the right?

The fuel tank fiasco completely ruined my day, and there's at least a 50-50 chance that it will ruin tomorrow too by keeping me awake tonight while I sweat out the question of how Van's intends to fix this. Replacing the center section is certainly not an option - it would require undoing something like 18 months of work.

It was too early to quit working, though, so I decided to finish up the oil radiator job by mounting it to the piece of duct that Pete had been working on. Easy, at the start, with just a couple of holes to get drilled.

A pair of nutplates installed.

Bolted into place.

A couple more holes to drill, some little plastic guiding cones, and some nuts and washers. Piece of cake!

Still too early to quit, so maybe we could get the stab back on after all. I started by cleaning up the loose bundle of wires for the trim motor. Those connectors can be replaced with a different type of connector as part of the imminent avionics installation, but I'n not sure that I'll bother.

From there, it all went down hill. The washers that have to be glued to the stab in order to get them positioned on the hinge bolt fell off as we were sliding the stab into place. I wasted half an hour or so trying to get the washers in place using tweezers and swearing, but it was no use.

I am beginning to lose my faith in tweezers.

We took the stab back off, grabbed some fresh washers that I had ordered the last time I ordered a bunch of "just in case" stuff from Van's, and glued them to the stab.

Then we went home. I'd had enough.