March 10, 2016 - Fit and Tack Weld Aft Fuselage |
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| With the forward end tack-welded, I was able to rotate the structure on its side. I immediately noticed that there was too much space between tubes in some of the joints, so I had to cut the tacks and adjust the fit, then re-tack. | ||||||
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| The two sides ultimately come together at the tail end and I had really worried a lot about how I was going to do that. | ||||||
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| It turns out that I was able to pull the two sides together with hardly any effort at all! I was amazed at how easily the steel tubing bent. | ||||||
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View from the front.
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I used the Dremel tool to cut the longerons at the tail end. I've discovered that steel wire and turnbuckles are extremely useful things when building a steel tube fuselage. |
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A turnbuckle in action. Available at the aviation aisle in your local hardware store.
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| It's important to have the tail straight and aligned. I used the 1 1/8" steel tube to do this. This is the steel tube that will actually be welded in later. | ||||||
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| I cut the aft cross-members tubes. | ||||||
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I hung a plumb-bob to make sure the fuselage is straight from nose to tail.
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| To hold the tail area in the correct position, I built a jig out of perforated steel tubing. | ||||||
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Doing so reminded me greatly of the Erector Set kit I had as a kid.
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| A good look at the tail jig. | ||||||
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| You may notice something is missing in this picture. Initially, I thought instead of using wire and turnbuckles for cross-bracing per the plans, I would use 5/8" tubing as some builders have done. The primary reason was cost, as the aviation-quality turnbuckles are expensive. So I tack-welded diagonal 5/8" tubing into my fuse sides. But I found notching the diagonals and getting a good fit was a nightmare, and the cross-member diagonals would be even worse. So I decided to go back to the wire and turnbuckles. It was easy to cut the tacks and remove the diagonals from the fuse sides. | ||||||
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| Tack-welding the aft cross-members. | ||||||
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| From another angle. | ||||||
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