Gasket - a prototype that doesn't fly

By IvanNik on Feb 24, 2019

10  579  13

Finally diceded to publish the build. Arms are too thin, a lot of vibrations. Plese use this failed build as wrong example :)

Main goals:

  • Light custom frame
  • Stretch X motor layout
  • Battery on top for good CG
  • Weight: 253g AUW

Inspired by (cloned) build: Featherlight 190 - 245g AUW 5 inch

After several tests: the arms are too thin => a lot of vibration on high throttle.
Negative result is also the result!

9/9/2018 gasket became an idea donor for new project: https://rotorbuilds.com/build/14252 (also light but with 2 new ideas - tubes and simple box desing)

Photos

Part List

Frame

gasket
Armattanproductions.com
$33.83

Flight Controller

HGLRC XJB F438 Omnibus F4 FC& 33A Blhel_S BB2 2-4S 4 in 1 ESC (2 builds)
Hglrc.com
$66.99

Motors

4 x Cobra CP 1407-3200KV Champion Series Motor (2 builds)
Getfpv.com
$71.96

Propellers

Gemfan 5x4 Carbon Nylon Propeller - 2 Blade (Set of 4 - Black)
Getfpv.com
$1.99

FPV Camera

Runcam Micro Eagle (308 builds)
Pirofliprc.com
$44.99

FPV Transmitter

TBS Unify Pro HV 5G8 - Race (SMA) (554 builds)
Getfpv.com
$29.99

Antenna

Lumenier AXII MMCX 5.8GHz Antenna (RHCP) (70 builds)
Getfpv.com
$14.99

Receiver

Flysky FS-A8S FS A8S V2 2.4G 8CH Mini Receiver with PPM i-BUS SBUS Output (91 builds)
Banggood.com
$9.99

Batteries

Tattu R-Line 4S 850mAh 95C (XT30)
Progressiverc.com
$19.99
Show stores (6)

Discussion

Sign in to comment

LionelFPV   Feb 26, 2019  
1

Hello,

This idea is awesome. I had a similar idea for a 3 inch more square like but using a similar arme frame plate concept. (however I can't do 3d designs ... ).
Your idea would enable freestyle people to have a super strong frame but still very light and with a very good CG.

Do you think it would be possible to improve this design by having at least 3 screws per motor, adding a X in the middle of the arme plate, and by beefing up a bit the arms?
Do you think it would be possible to make a similar frame with an X shape and not stretched X?
Even if the frame would weight 50-60 grams with the mods it would be such an awesome frame for freestyle and race.

IvanNik   Feb 27, 2019 
3

Thanks, sure it's possible: true X, strong arms, additional screws.
Maybe I will try v2 :)

M_Brems   Mar 07, 2019 
1

Definitely do a v2!

M_Brems   Mar 07, 2019  

It's pretty cool tho.. 😅 😃 Some small changes and it would be perfect! 😎

Hoppey   Mar 05, 2019  
1

I'm glad you showed this fail ... It makes me feel Not quite so alone in trying to figure out some of this drone stuff

Jodie Froster   Feb 25, 2019  
1

Love the ambition, lil sad it didn't end up a good flyer, but i'm sure the experience was awesome. I know the tooth fairy is a good design, and I wouldn't blame you for choosing that. I hope you refine your frame untill it's what you want. Flying your own frame is SO much cooler/more satisfying than building out a frame someone else designed. Also: your camera mount with the vtx antenna AND the cap all together looks good, AND it's an effecient use of space! CF tubes for arms do present some mounting challenges, but you could get the weight/low drag that you want. I'm not gonna beat the dead horse about the fiber orientation and cut direction, as I see several comments already (but that might be all you need).

Jodie Froster   Feb 25, 2019 

Ok, I saw your other post (the purple kwerd with the tube arms). I guess I was preaching to the choir. Nice work btw, love the awesome color customization!

IvanNik   Feb 25, 2019 

Thank you! you are absolutely correct: the process was awesome :)

fovea   Feb 25, 2019  

4inch as a nimble rocket than speed machine? sorry this would be very diffrent, but im 4"lover and would be very intressted on a flight footage on 4" and your impression about
thanks for post this build

erikspen   Feb 24, 2019  
1

If from Armattan, you'd have to rotate the DWG by 45d and add "along put weave" to the file name. They'd cut fiber orientation correctly that way. It does add cost, but very surprised cncmadness didn't just do it for you by default.

Q: What was the cost compared to Armattan's quote?

Problem with very-thin arms with low Width/Thickness ratio is they deflect a lot when torqued like a screwdriver shaft. Tubular arms don't have this issue; Hyperlow Vert's use a crossbrace to mitigate. Not sure what the width of a Hyperlite is, but that's probably as low as one should go.

IvanNik   Feb 24, 2019 
1

It doesn't matter how to cut unibody frame :)

It was a really thin arms.. The problem was on ~70% of trottle. So I got few packs :)
It's a design mistake not "cut" ot " wrong carbon".. actually

Kruizen   Jul 28, 2018  

This design is really cool! You might try simply cutting the carbon fiber along the arms for more strength and rigidity. I know I'll never ever buy another frame that doesn't do this - they break about 4x easier (ask me how I know ;)

IvanNik   Sep 01, 2018 

Thanks, you are right about arms and fiber orientation. I wanted unibody w/o any connections.
Finally I found HyperLite Tooth Fairy 5", see https://rotorbuilds.com/build/12179

Guides & Reviews

8 1,279  4
9 days ago

Black Friday Sale at BetaFPV.com - Save 20% sitewide with coupon BFCM (Nov 27 - Dec 1) FPV has had quite a journey. Just a few years ago we started racing drones around a track and doing flips over trees, but professional cinematic FPV is a more recent development. DJI has always owned the drone photography market, but smaller acrobatic drones are starting to enter the market. They have the advantage..

Read more
Aug 26, 2020

For the longest time we've been limited to 3 to 4 minutes of flight and lots and lots of batteries. With more efficient motors and frame designs it's now possible to push the envelope much further. This guide will walk you through the process of building a micro long range quad capable of flying 8-30 minutes and more than 4km. The build is moderately difficult, but with the right tools and steady hands..

Read more