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FTFC20 1939 Popular Aviation Special by Vimana89

Vimana89

Well-known member
#21
Here are my templates and a single sheet of foam with everything drawn out, showing that the design, in the size,scale, and method I have done it as a foamy, fits completely and easily on one sheet with room to spare. The four templates I used for this plane are fuselage(side), wing(half),tailplane(half) and vertical stabilizer. I altered the parameters of the wing and tailplane slightly. I was adding an extra 40mm in the center of each to accommodate the fuselage. To go more exact to the dimensions of the original, I eliminated the extra 40mm from both and accommodated for the fuselage. The smudges on the foam were mistakes in part placement for a good fit on the single sheet.
 

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Vimana89

Well-known member
#23
Started hand drawn plans, will continue to flesh them out. They are a little rough. They won't win any beauty contests, but if I get them scanned in 1 for 1 proper size, they will definitely work. The lines are a bit fuzzy in places but most people cut with a straight edge anyway, which will eliminate any small slop. Time to start putting the plane together next.
 

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Vimana89

Well-known member
#24
Took a break, time to build. Here is the design's one A fold. Made the fold channels a bit too wide, so I have some slop material on the edges made as neat as I can press it down. Everything is still 90 degrees and spaced properly, just aesthetic slop. Will try to get these perfect on the plan, but foam can vary even board to board from the same company in thickness slightly.
 

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Vimana89

Well-known member
#25
I have to sand the ailerons bevels, and then I'm at the point to start putting in linkages and electronics and testing them before mounting the wing and closing things up. This plane has one simple A fold, no curved fuselage components, and is further simplified in that the wing is fixed and not removable. Also, the tail plane and wing do not even have spots and tabs, they simply glue down to the fuselage with guide lines. The small size of this version and chord of these parts makes this more than strong enough. The fuselage uses an A fold rather than a side fold, with plates simply glued on, rather than removing the foam and leaving paper edges as per the FT technique used on the Scout. More advanced builders can easily change these features to their preferred techniques, such as side folds and paper edges and removable wings,but I purposely want even the full 1.0 version to be as easy and quick to build as possible with no sacrifice to performance.
 

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Vimana89

Well-known member
#26
Grabbed the 1806 radial off of the first RET version. I use a two piece 30mm motor mount that fits into the 40mm fuselage somewhat like a power pack, but each piece is aligned to preference for thrust angle.
 

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Vimana89

Well-known member
#28
Nearing completion. Got balance right with 850 2s! My nose is longer than the original, but with those old pylon motors, it had a lot of weight at the front so it could balance with the short nose. Lengthening the nose a bit was a practical change to better suit electric and achieve balance while being light. Otherwise, it really has the same profile as the original.
 

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Vimana89

Well-known member
#29
Took a break, came back, and finished up. Elevator has a bit of slop, it doesn't go all the way up to the max, but has enough motion to get the job done, probably nothing drastic like loops. I'll see how it flies first and maybe address this later. I need to set a bit of sub trim and she is ready to maiden.
 

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Vimana89

Well-known member
#32
Maidened today and tested many combos on 2 and 3s, tweaked CG, etc. this prototype is a dud. It doesn't fly right no matter what. I think using basics brand foam with the heavier paper and the 40mm less on wing span was a bad idea. It has some trim issues too, but they aren't the half of it. I will likely scrap this one and go back to the drawing board, using the successful AET model(which I still have up and running) as a base again, and maybe scaling up just a bit.
 

Vimana89

Well-known member
#33
I will be revisiting this build soon, taking everything that was good about the successful prototype and expanding it just a bit, rather than changing it to work around a different, lighter battery, or reducing the wing span an inch and a half to make it exactly scale(ish) or something at this point. My only real issues with the good AET prototype on 3s 850 is it felt just a hair heavily loaded and needed a hair more elevator authority. I'll use the same wingspan I had for that one again, but add a little chord too, which will make it look more scale without subtracting any wing. Basically, the span on the good prototype was slightly longer than the original balsa model proportions, but the chord about exact, so now I'll scale up the chord to match, which will be an overall very slightly wider and longer wing than the original that still looks pretty much scale. I'll add a bit of elevator, maybe a half inch, and try to maybe squeeze a bit more throw out too. more wing will give it a lighter loading, and more elevator is self explanitory.
 

Vimana89

Well-known member
#34
So, I adjusted the parameters of the wing to have both more chord and span. "More wing?terrible idea!!" Can't think of a situation that would ever be said, except maybe a supersonic plane. I made the VS a bit larger and shaped more like the original. I left the tail plane basically about the same and added 1/4 inch to the elevator. I have to make hard templates of the new VS and wing, and then I will redo the fuselage next. Mine has exposed foam core edges and a tight fit for electronics in front. These things will be fixed.
 

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Vimana89

Well-known member
#35
Going to widen and round the very bottom front of the fuselage. This will give me much more room for electronics to fit well, even with a B fold. The intake will be located as a chin scoop between the round front of the fuselage and the motor mount, to keep it off the ground on landing and not take in dirt.
 

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Vimana89

Well-known member
#36
Amended hard templates ready. What's not cardboard is 3mm foam. I can concentrate on tracing out and building the plane now, and if it flies as well as I want it to, I can use these same templates to trace up plans.
 

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Vimana89

Well-known member
#37
Four main pieces are cut. Next, I will work on the fuselage, draw up and cut out the extra plating, and start assembly. When the fuselage is more or less built, I will cut and sand control surfaces.
 

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