What could be done to reinvent the Affordaplane to a more homogeneous project?

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Victor Bravo

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Interesting prospect... Fritz' wing in Post 641 can possibly be built by putting the lower portion of the ribs down on the workbench like an old model airplane, then the tubular spars laid into the lower rib semi-circular cutout, then the upper rib cap assembled onto it. This could potentially yield a better or tighter glue joint between the ribs and the spar tubes (compared to an external "fillet" glue joint). It might also allow the wing to be built on a flat table with a lot less jigging and leveling than supporting two tubes on sawhorses?
 

FritzW

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Is this wing ready for an AP?
Not by a long shot. It just shows how the VP21-HWC rib idea could work with tube spars.

can possibly be built by putting the lower portion of the ribs down on the workbench like an old model airplane
That was the original idea with the VP21 but now I'm thinking a simple Styrofoam jig would be much better.

Bondo the saw horses to the floor, shim the jigs level and Bondo them to the saw horses.
EDIT: Actually there's no need to Bondo anything, it just has to be sort of close. The wing will twist until all the struts are on.
Tube Spar Jig.JPG
Tube Spar Jig 1.JPG
 
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galapoola

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Here's something I've always wondered. We see mixed material wings used successfully. Fabric over aluminum on Ercoupes. Wood over wood and foam on the SP-1. Is there a reason why a nice shinny piece of aluminum can't be bonded over those ply spars we see in that wing rendering? Ply should stay dimensionally stable if it's sealed. I have thought about how aluminum and wood contract and expand differently with temperatures but how much and would the bond pull away or the metal wrinkle?
 

Tiger Tim

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How would you install those ribs on the tubes and be sure that they remain vertical, and do not flip to one side or another?
Probably just glue them to the tubes and run crossed fabric tapes between the ribs at their thickest points, as you would see in a Cub. You probably don’t even need that but I’m a careful guy.
 

FritzW

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But they risk to flip at the junction of the upper and lower half, when you put them under tension,no!?
I don't think so. I think the nature of the finger joints on the diagonals would keep the rib from twisting/bending at the glue joint and the "saw tooth" joints would keep the bending from being focused on a thin line. ...but it'd be easy enough to add little 1/16" ply doublers.
 
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