What do you think about my Lexan scratchbuild?

So, after tons of trial and error to see what features worked and didn't work for me, i have come up with this as my daily driver. I started out with a SK450 frame and quickly moved to a custom wooden H frame that was way too heavy. I figured i would take a shot at trying to build a tricopter and have fallen in love with the T-copter style. Started out by making several wood variants until i found a good design and then transitioned into lexan for durability.

Here are some pictures and a video of this current version. Will try to get a parts list up later. Let me know what you think!

Demo video

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cranialrectosis

Faster than a speeding face plant!
Mentor
So it didn't break, the boom just folded back?

That was sweet. Love the clear Lexan too.

What's it weigh?
 
So it didn't break, the boom just folded back?

That was sweet. Love the clear Lexan too.

What's it weigh?

Thank you!

Unfortunately i haven't weighed it so not sure about that one.

As for the durability, I have crashed this one several times and just picked it up and put it back in the air. The front booms are only held in place by the tension of the bottom and top frame plates, so on a nose-in crash, they just bend back without crimping the ESC wires. The rear boom has one bolt holding it to the frame with a secondary zip tie support to keep it straight during normal flight. In a bad crash, the zip tie should break letting the rear boom swing to one side or the other to reduce impact damage. The lexan is damn near indestructible when it comes to crashes. The landing gear itself can easily be bent into a 90 degree arc and snap right back without any risk of breaking.

A good air frame for my flying style... 'Fly it like you stole it!' ;)
 

x0054

Senior Member
I really like your vibration isolation plate for the camera, it's a really clever solution! I may have to steal it :) Overall it's a very nice design, simple and clean.
 
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jhitesma

Some guy in the desert
Mentor
I like the lexan booms. Bummer that the holes through them make them stand out from some angles. I bet if you polished those holes they'd all but disappear. A bit of 400 or 600 grit wet dry sand paper and a 1/4" dowel with a slit cut in it to hold the paper followed by a q-tip with some brasso or car polish would make them nearly invisible. Should be able to flame polish lexan as well but I've never had much luck with that, some friends swear by it and have it down but I can't find the touch and never get good results.

I love the idea of an all lexan multi. But after swapping the body on my quick and dirty budget 250 from 1/8" ply to 1/8" lexan I found it a lot harder to see in the sky :) I have some acrylic rods I've been thinking about trying to make arms out of. Don't think the acrylic rods are strong enough though. Might work on something a little smaller sized for 5" props max. I need to dig those out and take a look at them one of these days. The lexan body was also heavier than the plywood which surprised me. Biggest problem though was I messed up assembling it and rotated one piece 90 degrees, and since my design wasn't as square as it should have been that led to some major warping when I assembled it. One of these days I'll find some motors and ESC's and get that frame back in the air.

You should really push to finish the minimal look. Imagine it with an afromini and spektrum sat:
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Or if you want to keep your flysky but clean things up you could grab an arduino pro mini and a A7105 RF module (About $5 total cost but you'll probably have to buy 2-3 of each to get them that cheap) flash midelics flysky RX software and have a small PPM with failsafe RX that takes just 3 wires to connect. The longer 6 wire harness is between the "brain" and the "radio". Since the antenna is part of the module on this module I figured having some length there would make it easier to mount the antenna. This bench tested great - but I didn't fly it because I got my spektrum sat RX and it was smaller and lighter and a cleaner easier solution for about the same price. But I already have a spektrum TX module for my radio, if I still had flysky I'd be be cleaning up the wiring on the LED and getting that board mounted :) I'm actually about to tear my knuckle quad down and put this same basic setup in. But in place of the afromini I'll be hooking a MPU-6050 sensor onto the arduino along with the A7105 and letting the arduino be both FC and RX at the same time. I've bench tested that as well but have to clean up the wiring a bit more before I can actually put it on a quad.
10576388_10152204261106805_647847512_o.jpg

Swap to some KISS ESC's and clean up the wiring a bit and this thing could all but disappear in the air :)

Now you've just got me daydreaming about how to make the most invisible multi...