Before I assembled the forward bottom skin to the center bottom skin, I need to test fit the landing gear weldments and match drill them to the side skins. There is an interference with the spar carry-through flange which must be ground away before the weldment will sit flat against the spar. Pictured below is the trimmed area before final filing and polishing. The cut gets very close to one rivet, but it is unavoidable.
After that, it was just a matter of reassembling the pieces which were all carefully marked with their part number and an arrow indicating their proper orientation, i.e., forward, up, left, or right as required. Since there were no parts to make this time around, the reassembly via cleco went very quickly. Please enjoy the following musical montage sans music:
When the firewall is attached to the side skins the joint is first sealed with a fire resistant silicone. This is designed to prevent exhaust gases from entering the cockpit. It has the added benefit that should the engine catch on fire, neither the passenger or nor the pilot will be inconvenienced by the smell of smoke.
Before the bottom skin is riveted on, the lower longerons are bolted to the engine mount weldments on the back of the firewall.
In this spectacular photo, the camera on it's own, decided the table top was the more interesting subject.
I didn't take many photos of the riveting process because Carolina and I were both involved. For most the the process Carolina was under the plane because she prefers to buck rather than shoot.
I like that photo because she is smiling. In the future I will show her that picture and gently suggest that this phase was not as bad as she remembers.
One of many long evenings of riveting is done. Mercifully, it's time to go back up to the house.
All together, it took a couple of weeks to complete this reassembly. There are hundreds of rivets in the side and forward bottom skins and along the center to tail cone joint. I can't say that this portion of the project was a lot of fun, just that it sure is nice to finally move on.
One of the really amazing things that the reader will not readily appreciate is the way the structure becomes very robust and unyielding as the rivets go in. It really is a wonderful thing to watch as the flimsiest of materials quite suddenly take on a strength that would be unsuspected to all but the structural engineer.
So, at this point the lower half of the fuselage is mostly complete. Enough of the structure is riveted together that the fuselage can now be self supporting. This means the fuselage can be turned over in a process known to builders as "Flipping the Canoe." Since the bottom of the fuselage is not flat, most builders construct some kind of cradle to hold the fuselage and to raise it to a comfortable work height.
Some claim time and effort savings if a giant rotisserie is constructed to allow the fuselage to rotate to any comfortable angle which will facilitate access. My motto has always been "If there is a way to save time, I'll do it no matter how long it takes." Here are a few shots to get the flavor of this little side project. The rotisserie is made primarily from rectangular steel tube, 2" x 1", a little bit of .75" square tube, and some 1" angle.
In the next posting the canoe will finally be righted, the rotisserie will be demonstrated, and the death march toward riveting madness will be a distant memory.
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