Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater

Sat, 17 Apr 2021

Building a Biplane: One Thousand Hours

Photo of a partially assembled biplane wing sitting on a
workbench, shot from above

As of about 10:30 this morning, I passed the 1000 hour mark on my Marquart Charger biplane build.

As milestones go, it's not terribly exciting, in real terms. I was working on attaching the pivot brackets to the aileron spar, and taking my sweet time about it -- two hours to drill six holes, but I was quite interested in them being exactly right, so that when the aileron swings up and down, it doesn't bind. It's a bit of a trick, with three completely separate pivot points on a piece of wood, but I figured it out.

When I started this project in earnest in 2017, I was optimistically hoping I might see it finished in 5-7 years, but that changed to 7-10 years, then 10 years, and now I tell people ten to twenty years to completion. If you look at the Hours Spent By Month chart on the build dashboard, you'll see that I had a few good months in 2017, but 2017 and 2018 were fairly lackluster for actual time spent on the build. Then 2019 was completely absent, and when the pandemic hit in 2020, my time spent suddenly explodes.

Chances are decent that I'll be fully vaccinated within 3 months, and I wonder what that will do to my dedication to this project. I know I'll keep working on it, but I don't know if social engagements will slowly creep in and start eating up the time I would otherwise spend in the shop. That could slow my pace considerably, but it might be good for my sanity.

Another complicating factor, as far as predicting my pace, is that I'm breaking a lot of new ground right now, as I assemble my first wing panel. I'm cracking new problems and working out new procedures. I'm having to order stuff I hadn't already predicted I'd need. But, once I feel reasonably confident with what I'm doing, I have a feeling the subsequent wing panels will go a lot faster. Sure, it'll take me several hundred hours to put together this panel, but panel #2 might go together in a hundred hours, or it's possible it might take just as long. I don't know.

I also need to keep in mind that those thousand hours I've spent have almost all been productive time: I have nearly all the parts built and ready to assemble for all four wings. Assembling the pieces goes a lot faster, since I've effectively been building a big wing kit. As I learn from the first wing, I reduce the things that will slow me down for the next wing.

The things I'm aware of that aren't done at this point is a fairly small list:

Ok, so it looks bigger when I write it out, but compared to making all the ribs, the wedge blocks, and jigging/welding/painting the wing brackets, it's not bad.

The big thing that happened recently is that I decided it was safe to finally glue the ribs to the wing spars. That's a huge step, because once you do that, it becomes a lot harder to work inside the wing. Suddenly all these ribs are in the way, and can't be conveniently slid out of the way. However, it was time, and once it happened, it unlocked all these other tasks. With the ribs fixed in position, I can install filler blocks between the ribs, I can make the ailerons (which have matching ribs that should line up with the wing's rib positions), and I can install the fuel tank area plywood. I've actually punted on the fuel tank area for the moment, until I can deal with the wing root fittings. I messed up and attached too-thick plywood to the wing roots, and have to deal with that before I can proceed.

The ability to move on to all these little jobs has been very freeing, and as a result I've felt much more productive. Before the ribs were glued down, I basically spent two weeks examining the plans and the wing from every possible angle, trying to figure out whether I was ready. It was time well spent, since it appears I didn't leave anything that needed to be done undone, but it felt like fairly unproductive time.

In any case, the arbitrary milestone of 1000 hours has come and gone, and I'm making good progress. Hopefully by the time another thousand hours has passed, I'll be done with wings, and working on the fuselage.

With any luck, I can keep up something like this pace. I've worked 625 hours in the last year, an average of 1.71 hours per day. I'd like to average 2 -- if I could do that, I'd make it to 5000 hours in just under five and a half years. Even if I stick with 1.7, that would only be six and a half years. Still, I think I'll keep telling people ten to twenty years. You never know when life will get in the way.

Posted at 23:33 permanent link category: /charger


Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater