Wednesday, January 13, 2010

Things that go Huh? in the night

It sometimes surprises me to find myself suddenly awake in the middle of the night wondering about some trifle or another. It's not so much the broad range of topics that can cross my mind while ostensibly sound asleep, rather it's how critically important even the most trifling thing can seem at the time. A couple of nights ago, I woke up in a near panic because I could not remember having run a string similar to the one that will eventually be used (I'm betting) to pull the stabilator control cables back through the aft bulkhead that would be used to pull the rudder cables. I eventually calmed myself sufficiently to get back to sleep by reminding myself that the tail cone is not yet sealed up. Still, it seemed odd that such a string hadn't been placed at the same time as the stab string. Could I have missed that step somehow in spite of the diligence that I apply to the practice of checking off every step as it's completed?

It wouldn't be until the next evening that I could get out to the hangar to see what was going on. It turned out to be quite simple: there is a step or two required before running the rudder cable string. There are a couple of small brackets whose sole purpose in life is to provide support for a couple of plastic bushings that will ostensibly help guide and protect the rudder cables. In fact, it is the installation of these little brackets that had me out driving in snowy weather on Tuesday night in order to pick up a borrowed 12" #30 drill bit. The directions have us cleco the brackets in place, then match drill a couple of holes using the extended length drill bit. In what turned out to be misplaced faith in the professed need for said drill bit, I braved the slippery roads in order to acquire it before starting the installation of the brackets.

On the plus side, separating the brackets from the now-expected Van's combo-pack allowed me the opportunity to try out my new tool:

Hot knife, it is my pleasure to introduce you to butter! The band saw makes a fast, clean cut that is orders of magnitude better than I have ever been able to accomplish with the tin snips or the hacksaw, and the icing on the cake is the additional excitement that arises from the risk, albeit small, that I could also remove one or more of my lifetime allotment of fingers.

It took a little bit of trial and error along with repeated trips back to the plan book to study the drawings to figure out the correct orientation and placement of the brackets, but as is often the case, it was patently obvious where they belonged once I managed to get them clecoed in:

Finally ready to use the drill bit that I risked life, limb, and automotive sheet metal to attain, I found that I didn't really need it after all. The little Craftsman drill fit in there just fine with my regular sized #30 bit:

Go figure. Someone at Van's apparently owns stock in Acme Extended Length Drill Bit Manufacturing, Inc. Me? I must have missed out on that IPO.

The drilling was the easy part; the spacing of these two rivets was, in a word, bitchy. One of them had to be drilled out and replaced as it rose out of the hole while I was pulling it, which was a first. Blind rivets are usually pretty much fool proof. Of course, when one aspires to be the best fool possible as I do, anything is attainable!

As I retrieved the plastic bushings from the little brown paper bag, I had a horrible flashback to the last bushing I had installed. That would be the 7/16" bushing that was somehow supposed to fit into a 6/16" hole, for those of you that may have missed that little ordeal. It was with great relief that I easily snapped these bushings into the provided orifice. I'm not sure what I would have done had they not fit, but I'm pretty sure it would have involved harsh language and a monumental tantrum.

I'm printing this picture and setting the print on my nightstand tonight, just in case:

Those were the last steps required before a large riveting job on the skins. The timing was perfect as soon-to-be RV-12 builders Don and Kyle were scheduled to arrive for a shop visit just a few hours later. Just let it be said that I have made good use of my high school literary studies, having often leveraged the lesson of Tom Sawyer's clever means of getting other kids to whitewash the fence that his Aunt Polly had instructed him to paint. As it turns out, the only thing easier than blind riveting is having someone else blind rivet for you!

And this is the beauty of the RV-12 in a nutshell. With a "normal" RV, potential builders worry themselves into a froth over not knowing how to drive rivets and wondering if they are even capable of being taught. They make pilgrimages to Oshkosh to attend riveting workshops. They spend hours practicing on scrap metal. The end up drilling out dozens of mis-driven rivets. They sink hundreds of dollars into tools. With blind rivets, if the EAA were to offer a seminar it would take longer to get everyone settled and go through the mandatory don't-blame-us safety briefing than it would to teach the actual operation.

I had each of the visitors pull a couple of rivets under my supervision and then simply turned them loose with a pair of cleco pliers and the air rivet puller. I went and worked on the RV-6, cleaned up the hangar a little bit, and generally made myself scarce while they riveted the entire tail cone. And the best part is, they acted like I was doing them a favor.

Oh, I am soooo good! I wasn't able to convince them to come back for my broom pushing seminar, though. I guess I have my limits.

All kidding aside, it's nice to have neighbors! Don and Kyle will be building their RV-12 down in the area of Jackson, Ohio. That's just a few minutes from Portsmouth, an airport I visit quite frequently. It'll be nice to stop by now and then to see how things are going for them. If nothing else, I'm pretty sure they have a good grasp of riveting fundamentals. They must have pulled a couple of hundred of them with no problems at all.

But the most gratifying thing of all was that those broken skin edges that I was so worried about after having molested them to within an inch of their lives snugged up nice and tight. No worries here:

Which is not to say that I won't be on the look out for other RV builders surreptitiously casting judgmental glances at the skin edges - I will. But I'm much less worried about it than I thought I'd be.

Here's the cone, just about ready to be sealed up:

Amazingly, it seems to weigh about 10 pounds. If the people that ride with us in these airplanes could ever feel how light and flimsy they are during construction, they'd never get near one! It's incredible how much strength they have once they're assembled.

No comments:

Post a Comment