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Old 10-16-2019, 05:56 AM
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invertmast
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With things progressing fairly quickly, i decided to take the time to refine the trailing edges of the wing components. The TE at the root was fairly thick at around 3/32 to 1/8” thick. Seeing as how the fullscale is razor thin on the TE, i decided to use some fiber reinforced body filler to build up the TE so that it could be sanded down to a nearly razor thin TE, in reality, i will likely keep it just under 1/16” thick to make closing the parts a little easier.







While that cured, i made up a stand using pink insulation foam so that the fuselage could be rolled upside to make finishing the bottom easier.





Now the work of correcting the bottom fuselage where the nose fairs into the main fuselage could begin. The main fuselage is curved inwards at the nose fairing area instead of flat, so it leaves a large divot. This area should be mostly flat (if you removed the nose fairing section) so the reinforced body filler was used to fill in the divot. Later i will use regular filler to fine tune the shape so it blends with the groove left between the inlets and the nose smoothly. This is one of those area’s that the cad model was completely wrong in and trying to correct it in Cad created more rebuild errors for the entire model, so it was deemed to be quicker to fix if by hand than in Cad. There is also very little complex structure here, so that make it an easier decision.








In one of the above photo’s you can see the outlines cuts that were printed with the model for the gear door and speed brake outlines. These are locating fixtures that will get mostly filled in to help locate the bottom fuselage vinyl cut surface detail piece.

This will also be a good time to bring up and explain one out of scale detail being implemented. If anyone has seen Brent Hecht’s 1/4 edf T-38, your familiar with how slow it lands and how the takeoff rotation is nice and smooth (unlike all of the jumpy T38’s from other manufacturers) and the landing rollout the nose is able to be held high for aerodynamic braking very easily.
I found out he moved the main gear forward a good few inches to make that possible on his. He made the recommendation to do the same on this model, but it looked to far out of position, so it was decided to split the difference and move the gear forward 1 1/2”. This will hopefully make for a smooth rotation at takeoff and nose high aerodynamic braking on landings



Well, that brings us up to the current status of the project. I’ve been short on time recently with fall sports for my son and other household duties, so time is pretty short to work on this thing. I also need to get my downdraft table design finalized and built so i can do more intense sanding in the shop without dusting up the entire place.