While the Challenger Rony bracket issue is concerning, we're not talking multiple failures. The biggest issue was the inability to properly inspect it.And taking a lesson from the Challenger (IIRC), that is one load path that needs to be engineered and fabricated very carefully. No second chances with that one.
If you find elegance in simplicity...What’s out there for wing and strut mounting options on an aluminum tube cabin plane? I’m picturing a square steel carry-through across the top and steel strips tying in the struts across the belly. Is there anything more elegant than that?
On my Minimax via 1992 plans it is a 6061 T6 channel thats cut down in the center. It gets bolted in so that helps:If you find elegance in simplicity...
The HiMax uses a 1 x 1 x 1/8 2024 C channel for the spar carry throughs and a 3/4 x 3/4 x 1/8 2024 C channel on the floor for the strut attach points. ...scarry to look at but it obviously works. (I've never heard of a HiMax falling apart).
Because of my size, and the size of the yellow stripe down my back, I'd look real close at that though.
No added complexity in designing the gussets. They would be the same, just bent to a 60 degree angle instead of 90 degrees....Would the weight savings in three tube construction be worth the added complexity of designing gussets ( and maybe Fritz's printed widgets) that would work for that scenario?
My bad, I was suffering from an acute case of cranial rectalitis when I wrote the original title. My actual intent was to include all sorts of small single seat high wing airplanes, ALSO including the style of the Baby Ace, Sky Scout, Texas Parasol, Heath Parasol, etc.The 4 tube makes it easier to contain a human form, but in context of this thread title, the human will straddle the fuselage, making a 3 tube viable.
I'd argue that a 3 tube fuselage is much faster and easier to build if you have the right jig.Because of all that, I will bet dollars to donuts that the four tube fuselage is some modest amount easier and less effort/time/head-scratching to build than the three tube fuselage.
Once again Fritz from one SW user to another, how on earth are you so fast at cranking these out. Your jig looks amazing. I had a design for the Skylite for a jig, but it was not as nice nor refined as yours. I will once again follow your lead.I'd argue that a 3 tube fuselage is much faster and easier to build if you have the right jig.
...and before the naysayers jump in to say it's way too complicated and they can do it faster and better with a hammer and 2x4's, blah, blah, blah...
Once the fuselage model is done it only takes an hour or two to pull a jig off of it, and that only has to be done once. Another hour or two to cut the jig (less than an hour if it's XPS foam from the box stores). So, from fuselage model in CAD to a finished jig would take an afternoon. The second guy, who doesn't need to draw the jig, could do it on his lunch hour.
This one is a welding jig so it's beefier than it needs to be for a T&G fuselage.
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T&G would be light enough that you wouldn't need castors, you could make one like this out XPS foam
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It's fast, simple, cheap and works like charm
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