Completely 3D Printed Mini Mustang

[Grifflyer]

that AWESOME! if it's successful are you going to post the plans on thingiverse?

 

[BryHaley]

I'm gonna post the STLs and the CAD file itself ye

 

[DKchris]

That got me curious and apparently you can actually print foam

https://3dprintingindustry.com/news/now-can-3d-print-memory-foam-34265/

Problem is it's not rigid foam, but rather something more akin to memory foam. But it's that's possible, maybe printing rigid foam is too. Someday!

I'd have to design it a lot differently and I definitely don't have the tools to do it, but a present-day idea would to be to print out a prototype, make a mold from it, then inject mold a foam version of it.

I've seen printed elastomer foam before, but only in connection with fluid based printers; Filament based is definitely new.

Heh heh........" memory foam". Am I the only one to immediately imagine the following scenario?: You print your semi rigid memory foam model, take it to the field and fly it around for a bit with the usual piles of comments from the other pilots. Then you more or less deliberately "wrap" the plane around that one tree, that always seem to stand at one of the corners of the field. EVERYONE laughs out loud. When you then go and "peel" your plane off of the tree and it slowly just returns to its normal shape, and you relaunch it as if nothing had ever happened........that silence would be truly priceless........

 

[BryHaley]

Little test for y'all. Still some tweaks and things here and there but it's close.

I hadn't planned on using those metal hinges but the shipping tape hinges just weren't working out too well (except on the elevator) and the shipping tape + hot glue hinges I tried last time were causing the servos to bind. The hinges work out pretty well but I'll have to find prettier ones next time lol.

Before balancing, with a single 3S 850 mAh battery, it was noticeably better than a 1:1 thrust to weight ratio, but it was tail heavy.

Moved the power pod forward a bit, added two ounces to the power pod, and threw in another 3S 850mAh battery just cuz I had room. It's now balanced, and I'm right about at a 1:1 thrust to weight ratio. I'll take it! I could move the power pod even more forward and take out a battery if I want to prioritize performance over flight time I suppose.

 

[BryHaley]

As promised, here are the STLs for printing, and the CAD file for your viewing pleasure:
https://www.thingiverse.com/thing:2822912

Note: This is pretty much just an experiment. At the time of writing this, I have not yet maiden'd this plane, though I will soon. It's got a roughly 1:1 thrust to weight ratio (with two 3S 850mAh batteries and an added 2 ounces to the nose for balance) and it balances, so it'll -probably- fly, but no guarantees. Dimensions are similar to the foam board FT Mini Mustang. The first version of this design was built directly from the foam board plans, but that came out ridiculously heavy. Version 2 here is completely my own design (apart from using some P-51D blueprints for reference), but obviously the design is inspired from the FT Mini Mustang.

All that said, if you just want something to fly and don't really care for the novelty of a 3D printed aircraft, just get the FT Mini Mustang speed build kit and call it a day. This will take more time and effort and offers few advantages.

This design has a lot of mistakes. It's the first plane I've ever built in a CAD program and is definitely the most complex thing I've ever built in CAD, and I learned a lot from doing it, but if I were to start over now I would've designed it better and spent less time on the design. However, since like I said this offers little advantage over its foamie sister design, I will likely not invest time into a version three - I'd rather design aircraft that would be more difficult to build with foam, and doesn't already have FT plans (some WW2 Japanese aircraft come to mind). I have uploaded the Fusion 360 save file if you wish to take a look.

This was designed with the FT Power Pack F in mind, but you could (and probably should) fit a beefier system in it. The fuselage is much more spacious than the FT Mini Mustang, and with the Power Pack F it needs added weight to the nose to balance anyway, so getting a bigger more powerful motor and a bigger battery instead just makes sense. With how heavy it is, the extra power would be put to good use. I will, however, maiden it with the Power Pack F as I consider that the "baseline" of power it should have.

Warning: I didn't take the time to orient each piece into its ideal printing position, sorry. It should be fairly obvious which way they're intended to be printed, though. Generally fuselage pieces are printed nose down, no support (use 15% infill for the Fore Fuselage piece, and 5% for all others); tail pieces are printed flat, 10% infill; wing pieces are printed with their leading edge on the build plate, using "touching buildplate" supports. After printing, remove the support scaffolding that is included in the design (the length-wise supports in the fuselage; leave the horizontal struts).

After the maiden, I'll write up an article about what I learned, what the build process was like, and hopefully have a successful flight video

 

[DKchris]

I would strongly suggest you put a strip of tape along the hinge line to close up the slit between the wing and ailerons. An open slit that size will allow the air to pass from the high pressure side of the aileron to the low pressure side, reducing the effect of the control surfaces. A very narrow slit is ok, no opening is best.

As it is not acting as hinge, the kind of tape i not so important, it just has to close the gap.

 

[flitetest]

Wow, I cannot wait for this to get up in the air! Good on ya my friend! How long till we see that sweet sweet flying footage?
Keep up the great work!

Blessings,
Stefan

 

[BryHaley]

I would strongly suggest you put a strip of tape along the hinge line to close up the slit between the wing and ailerons. An open slit that size will allow the air to pass from the high pressure side of the aileron to the low pressure side, reducing the effect of the control surfaces. A very narrow slit is ok, no opening is best.

As it is not acting as hinge, the kind of tape i not so important, it just has to close the gap.

Yep, already did that shortly after taking that video

 

[BryHaley]

Wow, I cannot wait for this to get up in the air! Good on ya my friend! How long till we see that sweet sweet flying footage?
Keep up the great work!

Blessings,
Stefan

What a coincidence, I'm literally watching your guys' "3D Printed Plane Meets Blizzard" video as I type this, haha.

Hopefully soon! Unfortunately living in suburban California, I'm gonna have to travel a bit for a suitable place to fly this contraption. Doesn't help that it's been windy lately too! I'll see if I can't pull something off this weekend maybe.