Crazy idea: 6mm motors octopter


Eventually i will, but i don’t know if that will happen next year or next decade :rofl: What i need is a friend that already owns a 3d printer and knows how to use it properly. Then i should go his place every saturday and pick something to print, hehehe


I uploaded the new version of the frame to Thingiverse:


I don’t have a 3d printer, but i have 6mm straws…

6mm motors fit perfect on the straw. Only have to splice a few wires, and it’s done. Tomorrow i’ll check how it flies


Genius :smiley: that thing should have a ton of power!
Try not to melt the straws when soldering :stuck_out_tongue:


that thing… is going to RIP!!! :smiley: amazing work!


Actually i was going to use e010 stock motors, but ruined two of them in the process (pushing the props when motors already mounted) So, it has now two sets of racerstar black and red motors. It MUST have power.

I’m not worried about melting the straws. The first thing is going to melt is the hot glue i used to join the motor mounts to the arms… Let’s see how it handles after some minutes flying.

Sadly i didnt have the time to finish it before going to work… Just some wire splices to finish it, because the motor wires are not long enough for a 137mm frame…


Errr… i just tested it and, as it is now, it is unflyable. I’ll upload some dvr footage when i can. The e010 board is not ment to fly in such a big frame. Also, i’ve been having some weird drifting. Now i’m used to my “hobby” flight controllers, so when i go zero throttle i don’t loose control of the quad… but with this i do… And flying again with that crappy e010 transmitter is just… crap! The vtx is spoiled, i think it magically survived some magic smoke but since then range is reduced… Besides that, i found that a 240mah lipo lasts little time in this setup

So, it needs some major upgrades, but with those powerful motors and big props it has lots of power, and the frame is really ok! :sweat_smile:


Hey AAA, I was wondering if the 40mm tiny 7 props would work on .8mm shaft with a couple pieces of dental floss. Have you tried, and would that give more trust?


Those old tiny Ethos nano/Estes Proto had really neat 6mm motor mounts that I had used to make lightweight frames before. The Ethos mounts had slots in the bottom that you could slide small carbon fiber tubing in. Not super durable but extremely light for a frame.


Didn’t try that, but that’s a good experiment to do. You have to consider that the tiny 7 props are considerably heavier than the props you would mount on a motor with 0.8mm shaft. The weight of a set of 4 tiny 7 40mm props is 1.7gr. The weight of a set of regular tiny whoop props is 1.1gr. That can have an effect on how motors perform, maybe motors can get very hot and reduce its lifetime. But, of course, this has to be tested to know for sure. Anyway, the tiny 7 props should have more thrust, as they have a lot more surface in every blade to push air.

I only know 2 kinds of motors with 0.8mm shaft: 0615 and 0716 motors. I suggest to use 0716 motors for this test, since they can handle the extra weight of the props better than 0615 motors.

You can try the dental floss fix. I only tested the needle and loctite fix. Maybe the dental floss is more effective to cover those 0.2mm of difference


I was looking for 6, 7 and 8.5mm motor mounts to make homemade frames. Only found picnic quads motor mounts, but they’re between 0,70 and 0,95$ a piece. I would like to get a bunch of them, so the price would be high enough to make me think of alterenative solutions, such as the 6mm straws that i had at home (I found packages of 200 7mm straws for 5€ in amazon - and that’s expensive for plastic straws, but maybe i can get 2000 motor mounts from it) Sadly, didn’t find 8.5mm straws.

Straws are also very light. The weight of my straw-octocopter frame is just 5gr. They’re not as rigid and strong as a carbon fiber frame, but for 6mm motors, they’re quite durable, and way cheaper!!

I plan to do some more frames using straws. It’s a funny and cheap way to experiment and try crazy designs you wouldn’t do with other more expensive materials


Yeah, I totally dig the straw idea, that landing gear is great!


Isn’t it cute?


Made this frame to be able to test the Blade Nano QX props (same as the octocopter props) as i don’t have any other frame for 6mm motors (tiny whoop frames don’t fit those big props)

Still have to figure out how i’m gonna mount the camera, that’s why it has those extra pieces of plastic in the front and rear. When i do, i may be able to shave a little more weight from it


This thing isn’t super responsive, but seems to be fast. Didn’t have the chance to test it outside cause it’s too windy.
The problem is that it wobbles a lot and motors (racerstar red 0615) get very hot, so hot that the hot glue that joints the motor mount to the arm starts melting a little bit

I guess that changing pids i’ll be able to fix the wobbles, but don’t know what to do about the hot motors. Maybe the wobbles are causing the motors to work harder and with correct pids that will be fixed too?


Maybe, hot motors can be caused by a few things but in my experience it’s usually prop involved lol.


yeah, in fact those are the biggest props for 0.8mm shaft that i know so far. I thought 6mm motors should be able to deal with them. I guess i’ll go back to my trusty GW008 props. They provide good thrust and they’re very durable, not like these, you just look at them and they break…
Also have to rebuild that frame… Not as durable and bendable as i thought it was…


Back again with my octocopter!!

It’s been some time since i built the frame and did some tests with an e010 fc board and a crappy camera. That was not right. An aircraft so much bigger than a whoop (135mm) can’t fly well with that board.

I had to wait but now it has a camera and a FLF3 evo flight controller. Camera mount is a bit messy, i know… After raising P and D a lot, it flies really well, but still couldn’t tune yaw ok. Yawing is not accurate, it has some residual yawing after releasing the stick, but it’s totally flyable. Don’t know if i’ll be able to tune it or if it’s just something that happens because this flight controller has only 4 channels for motors, and not 8. Besides that, being this a quadcopter flight controller, it flies awesome with 2 motors soldered to each pad.

I tested it with 240mah, 500mah and 720mah, and noticed little difference between them. It should have more power than you can see in the video below, because my batteries are already a little bit degraded.

Now i want to make the arms a little bit shorter. Those props are big and still it there’s some separation between them

So happy with this build, so fun to fly!!


Wouldn’t it be great with 12 motors? Maybe it would be more stable, with one more motor between every pair. Will this board be able to handle 3 motors in each channel? I don’t want to burn any fet, but i’m just tempted to try


Just a teaser of my new build, another straw frame 6mm motor octocopter

Still needs a camera, but flew it indoors just to test it and it is a f**ing rocket!! Hope that 4 more grams don’t slow it down much.

Making frames with straws is a lot of fun!!!