The Horizontal Stabliser (HS) is the longest single piece we’ve had to assemble so far – we have to exit the workshop completely to turn it around, so it’s the first piece where we’ve had to plan and think about how we use the space. Nothing more annoying than manouvering it into place, only to find you’ve missed a rivet and having to turn the bloody thing around again! The next such challenge will be the fuselage, where we really won’t have any room to spare!
Over the last couple of weeks we’ve been priming and riveting the various ribs and spars that make up the internal structure of the HS, and we’re now ready to start assembling them in the outer skins and riveting the final piece together.
To hold the HS steady whilst we’re riveting the ribs onto the skins, we had to make a series of jigs out of plywood, with aluminium angle attached to the bottom so they can be clamped along the bench and moved around as different parts of the structure need support. There was some guidance in the instructions about how to do this, but it did say not to worry too much about the shape – it doesn’t need to be exact. They’re right, as you could spend hours getting them precise when it really doesn’t matter, they just need to be the correct approximate shape so that the skins and internal skeleton are supported.
I guess we’ll save the accuracy for the bits we’re actually going to fly!
It’s worth spending some time getting rid of the worst of the splinters and covering the jigs in duct tape so they don’t damage the skins while they’re sitting in them.
The nose ribs are the first parts that you rivet into the skins – a nightmare from an access point of view, definitely needs two people, and the one with smaller hands (guess who…) needs to hold the bucking bar – there is just no way that a normal-sized adult can get their hand plus a lump of metal into the gap.We actually found that there were some rivets only I could reach as J didn’t fit, but some others he had to hold the bar as it needed some odd angles that only someone with a larger hand span can achieve. I suppose that’s the definition of teamwork (read: we would be utterly screwed if we tried to do this with just one of us)!
Once we got a technique that worked, it went quite quickly, but we were constantly scared of dropping the bucking bar (a solid lump of tungsten) onto the skin and damaging it irreparably. We recommend putting some screwed up rags in the bottom to protect the skin – it gives you peace of mind when you’re balancing precariously trying to reach an awkward nose-rib rivet!
We’ve been working on the rivets for the front spare and the rest of the ribs since then – will post again later this week when we will (hopefully) be finished!