Learning to Build with EAA SportAir

OK, so I don’t really have any building to do right now.  In fact, I’m 400-some miles from home, writing this in my parents’ living room on my Christmas mini-vacation.  But this blog is in dire need of content, so I’m going to write a few posts about things I’ve done as I prepared to embark upon this RV project.
Anyhoo, one thing that I fidgeted about (probably like every other new builder out there) was the skill set I was going to need to build my plane.  I consider myself to be a pretty handy guy, but all this sheetmetal and rivet stuff was definitely outside my realm of experience.  Being a serial researcher, I did a lot of Googling, read lots of information, and watched innumerable videos on the subject of riveting.  I felt like I had at least a decent handle on the mechanics of the process…but of course, there’s generally a world of different between having the book knowledge and actually performing a task.
As such, I was thrilled when I got an email informing me that there were going to be EAA SportAir workshops in the Atlanta area.  It didn’t take much thinking on my part before I signed up for the Sheet Metal Basics class.  Basically, over the course of the class, I would construct a small wing section, and learn about riveting and various other tasks along the way.
So one cold November weekend, I got up way earlier than usual and drove myself to the Aviation Institute of Maintenance.  A couple cups of coffee raised my spirits while everyone got the general introduction and we broke into our individual groups.  The first part of Saturday was spent in the classroom, where our instructor covered such topics as tools, materials selection, fastener types, edge distances, and lots of other information. (I don’t have the booklet handy, so I’m going my memory here)
Then it was into the workshop, where we got our build partners and started on our first practice project.  This was a fairly simple thing, just a couple of bar stock pieces and an aluminum angle section that had to be marked, clamped, drilled, and riveted together.  Here, I learned an important lesson: The rivet squeezer beats the rivet gun any day.  The first rivets I squeezed were lovely; it turns out squeezing is pretty idiot-proof.  My first attempt at bucking, however…different matter.  Coincidentally, I also got my first experience drilling out rivets as well. (Along with my first time destroying a hole while trying to drill out a rivet. Oops.)
Well, that was educational.  On to the real practice project, the wing section.  For this project, we had to form a couple of ribs, rivet together the wing skeleton, then clamp/mark/drill/rivet the skins.  My partner and I succeeded in finishing the skeleton and getting the top skin marked before it was time to quit for the day.  The next morning, we went back to work with vigor, drilling the top skin, only to discover…crap.  Bad edge distance on one of the ribs, and I was sure I left plenty of room.  Well, that’s why it’s a practice project…we compensated by drilling an additional rivet hole with proper edge distance.  And you better believe I was way more careful with the bottom skin.
The finished product, all things considered, wasn’t too ugly.  Well, except for the control surface section, where it turned out our skin was bent incorrectly, and thus didn’t line up quite right.

Finished wing section

The fruit of our labor

I can say without reservation that this class was worth every penny.  I probably could have figured a lot of this out at home with the practice kits from Van’s, but I would have lost out on having an experienced eye to help out and offer useful tidbits.  I came home Sunday evening really feeling like I could build an actual airplane.  We’ll see how long that feeling lasts when I get real kits to work on…
I also gained a real appreciation for the prepunched kits that I’ll get to work with.  All that clamping, marking, and drilling provides a lot of opportunity for foul-ups; I’m glad that the vast majority of that work will be done by CNC machines at Van’s and not in my garage!
(Oh, and I got to take the wing section home.  At some point, I’m going to paint it and put it on my desk at work.  Should make for an interesting conversation piece.)

Posted in Preparation

No, I didn't give up already…

Wow, six weeks or so since I last put something here.  Impressive, and not necessarily in a good way.  The good news is that today I made the big jump.  Sometime around midday today, I faxed my order form to Van’s, and presumably my empennage kit will be on its way to me in the near future.  Fun time is about to begin.

In the meantime, lest anyone think I’ve been doing absolutely nothing the past month and a half…well, I’d say you were wrong, but not entirely.  Obviously no building activities have taken place, but I have been gradually filling out the workshop.  In addition to the workbench I built in our last installment, I now have a 30-gallon compressor, a bench grinder with Scotchbrite wheel, a shop vac, and some other assorted bits and pieces that will come in handy.  Which is good, since I expect I’ll be putting them to use in the very near future.

Stay tuned for actual build stuff!

Posted in Preparation

Project planning

So, there was no actual work on the plane today, at least not in a physical sense. After thinking things over, I’ve decided not to continue with the HS SB until I can get my hands on the rivet removal tool I mentioned yesterday. Given the challenges I had removing the existing rivets, I think trying to use similar techniques on the annoying ones just poses too great a risk of damage. Also, the tool is only about $60, which is quite a bit cheaper than what it would cost to replace substantial portions of the HS. Also, it’ll probably come in handy when I get around to doing another SB for the aileron hinge brackets on the wings – that’ll also involve drilling out some rivets with not-perfect access.

So that raised the question: what to do instead? And that question, combined with some discussion with the neighbors over coffee this morning, got me really thinking about how things need to proceed from here. As I’ve probably mentioned before, the goal I’m working towards is to have the plane ready to go to Oshkosh next year, and it’s a pretty lofty goal. Meanwhile, I’m at a stage of the build where work isn’t nearly as well-defined as it was earlier in the build. There’s a lot of stuff that needs to happen, and a lot of the stuff is dependent on other stuff. and some of that stuff is dependent on purchasing big-ticket items that are going to have lead times.

For example, while I haven’t inquired directly, what I’ve read indicates that Whirl Wind is running about a three-month lead time on props, and lots of people have stories of things taking even longer than quoted. Similarly, Van’s will have about a ten-week lead time on my finishing kit. For the engine, James at Titan said it could be as little as 30 days, but they’d be happy to work with me to “schedule” a delivery window that made sense to me. That’s pretty helpful – while I do want to get in on the Oshkosh discount by placing my order and getting my deposit down by the end of August, I doubt I’ll be ready for the engine by the end of this year. And the less time that engine spends sitting around in the Houston humidity without running, the better.

So this brings us to the crux of things: how do I know when to order these items? Waiting too long will definitely delay the project. Ordering to soon causes other problems, even if it’s just storing large items (like, say, the canopy) for a while.

Anyway, with this in mind, I decided to take today and start doing some real project planning. I skimmed through the remainder of the construction manual, writing down major tasks, and noting any dependencies they had. For example, before I can work in fitting the sliding canopy, I want to have the aft upper skins in place, but before I close off major access to the tailbone, I want to have most everything buttoned down back there, which means I want the elevator control system done, wiring runs to the tail completed (for lights, trim, possibly antennas). And on and on it goes.

So far, I just have a big ugly list of tasks – now I need to work out some way to visualize them, so I can get some overall sense of an order of operations. Once that’s done, I should be better equipped to make decisions about when to place these orders.

Making OSH next year is definitely going to be a tall order…but it’s sure making for a good source of motivation.

Posted in Preparation