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Old 04-18-2013, 02:20 PM
  #40  
Ravivos
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Default RE: Old JHH F-4 airframe conversion

Got some work on the wing,
as i proceed, and the layers of the old paint are slowly peeling away, it seems that the wing is in a rather bad shape, as the previous builder of this plane obviously wasn't thinking of the proper way it should be built/repaired.

so, as i mentioned before, when i opened the center section of the wing i found no beams nor spars to hold the two halves together.
spend some time thinking and decided to build the entire spar structure so it will carry the load of the landing gear (instead of the foam) and will act as a proper spar able to take the abuse of a turbine flying speeds.
i've built the structure that you can see in the picture, which have the plates for the landing gear,
i then implemented it into the wing using a polyurethane glue (Gorilla), which is absolutely perfect for gluing the wooden spars into the foam core.
once it was all align and the wing was leveled, the structure was glued into place and with couple of things in mind -
first - it should be able to withstand my not-so-perfect landings, so the top of the wing will be partially sheeted with a carbon fiber cloth at 90degs, this will provide an excellent top skin strength and will prevent the wing from collapsing on those negative Gs.

once the structure was in place, I cut the wheel wells,
as for the spar and its ability to take the high G turns, I've used a unidirectional carbon fiber tow (10 strands of 12K carbon tow) to create an I-Beam that will prevent the main spar from collapsing and withstand the pulling forces generated on the bottom of the wing at positive G.

there still a lot of work to be done, as i need to design and create every little piece of this flying puzzle.

Thanks.
Ravivos.
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