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Build Log
GoodLuckBuy 6-axis 290mm Carbon Fiber Hexacopter Multi-rotor Frame Details
Components
Build Recap
Note: This is a recap of my experience as documented in this thread on FliteTest When I first started building multi-rotors about a year ago, a guy showed up at the local field flying one of these frames with a pixhawk clone. I had my eyes set on the original Blackout Mini Hex but decided to purchase this frame instead since it was less than half the cost. Unfortunately, there are some weak points in the design and general overall lower quality versus the 'original' but it is still a cheap alternative. It would serve well as a small aerial filming rig to carry a GoPro but I would not recommend it for any kind of aggressive flying or racing.  The first thing I did was swap out the cheap blue rubber dampeners with some black ones I got from HK.  I took some detailed pictures of the carbon fiber layer with a cheap toy microscope. The cross-section (last picture) is from one of the front arms, which measure ~2.5mm thick    Comparing the cross-sections, on the Blackout you can see each individual layer clearly and cleanly without magnification.  The knockoff spider hex cross-section magnified on my last picture, which you can't really make out the layers well even at a magnified level. The spider hex from GLB is made with a matte finished carbon fiber, and visibly the cross-section looks different because it is a G10/CF sandwich.  These are some things I am a bit concerned with: CF Issues
Non-CF Issues
I put a Naze32 FunFly on there but had some trouble because it kept wanting to pitch/flip forward and the throttle was incredibly sensitive. In the video above the battery was mounted directly in the middle underneath the frame and when I put the cage on top and the battery on top of the cage, it was better but still bad. I fumbled around with the Tx settings and motor mixes but was able to diagnose the issue was a simple CoG problem due to builder error... . I wasn't using the frame as it was designed to be used. The frame comes with six hex standoffs to be used as landing gear, and is designed to carry a GoPro underneath on the floating battery tray suspended by the rubber dampeners. I was flying with a Mobius on top instead of a GoPro, and chose to not install the hex standoffs/landing gear nor to use the actual battery tray. Instead, I put the battery on top of the cage, which doesn't extend as far behind the hex as the tray does and doesn't offer the proper balance to keep the correct CoG.  After moving the battery down to the battery tray and pretty much hanging it off the back, the hex balanced out and flew without issue.  I decided to move the vibration dampened battery tray to the top of the cage, which added the extra support for the battery hanging off the back and fixed the CoG. I also flashed Harakiri TestCode3 to my Naze32 and removed all expo settings from my Tx and the hex flew much better. Then I had my first decent crash and ended up in a tree.  This was right after a dive from about 100ft up and trying to pull out from under another tree. Only broke one (front) prop and damaged the other (front) one.  You can also see the little stubby landing gear I attached under the frame made from a couple nylon hex standoffs and some 'screw cap protectors' from home depot. They work pretty well, give way during a (really) hard landing to help absorb some of the force and are cheap to replace if they do break. The video below was my first time ever attempting flips or rolls and I crashed and broke one of the middle arms of the frame. Here are some better pics of the carnage where you can clearly see the G10 sandwich:     They don't sell replacement booms on the website, but I contacted customer service and they said I could order one directly just to let them know which one. Instead, I managed to fix the broken boom using popsicle sticks, superglue and a couple clamps (woohoo!)   I put wax paper hoping it wouldn't stick but it still did a little bit, I removed some of it with a hobby knife.   The popsicle sticks worked great:  Here's a strength test video of the repaired boom. One of the brass standoffs bent and subsequently broke after having another crash. I did a roll right into a 75ft tree and luckily fell all the way through and was able to recover the hex without having to climb it. None of the arms broke, but all of the props did:  When I tried bending the standoff back it snapped, so I just used some superglue to hold it back together for now. I also moved the camera plate back to the bottom and made my own smaller mobius plate:  I was a little bit worried about the mobius sitting so far back that it would get the front of the frame in view, but it didn't. The hex flew great so I took it out to the first Aerial GP US FPV Race in October 2014 at Apollo Field. It won first place in the open class, only due to others crashing out, but a win is a win in my book. It was my first time ever racing, and didn't have any practice on the track before hand. Here's my video from the final round: I also posted up the video from my first round where I was going a bit slower figuring out the track and how to do everything. Ultimately, this frame doesn't really have much carbon fiber in it, it's just a thin sheet over fiberglass core, which doesn't add any strength really, and the standoffs and hardware (screws/nuts) are too small (2.5mm vs 3mm). It doesn't really crash well and I probably should not have been doing the flips and rolls and such with it, so I upgraded to something that can handle harder crashes without breaking. The EMax 12A ESCs and DYS 1806 are going to be moved into two ZMR250 with DragonFly 32 Pro flight controllers on them. Check back for more build logs coming soon. |
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Last edited by califrag; Jan 15, 2015 at 03:30 AM.
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