S500 Quad Crash - Need help with why

[Vermiform]

This is my learning quad and my first build. Appreciate any and all advice, criticism, sarcastic comments, etc.

HK S500 with a Mobius 2-axis Gimbal.

Flight purpose was to test and tune 2-axis Mobius gimbal. Winds were gusting around 10 miles per hour intermittently. This is the 4th flight with gimbal. Not sure what caused it to lose power at the end. Both self tightening props on port side spun off when engines stopped abruptly. Battery had more than 70% of power left.

Damage was very light. Broken retract lading gear on starboard side (what broke most of the fall) and a couple plastic stakeouts that supported gimbal.

Quad specs here:

Quad Frame: HobbyKing S500
https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=66873

Motors & Props: Multistar 2212
https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=66405

ESCs: Afro 30 amp
https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=39708

Flight Controller: Thunder QQ Super
http://www.hobbyking.com/hobbyking/...r_QQ_Super_Multi_Rotor_Flight_Controller.html

Battery: Multistar 3S 3000mAh
https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=63534

 

[tstrike]

Check your solder points especially your battery power. It looked like you were pushing it around quite a bit, easy enough for a cold solder joint to crack.

 

[Vermiform]

Check your solder points especially your battery power. It looked like you were pushing it around quite a bit, easy enough for a cold solder joint to crack.

No solder points per say. I have this thing snaking throughout the frame using bullet connectors.
View attachment 24444

Yes, I know that this is a piss poor way of doing it. I've since upped my soldering skills and have a PCB frame inbound. For now all bullet connectors are heat shrinked to protect them.

I also must note that the gimbal is being powered by a JST plug that is also soldered to that breakout cable (it came with one soldered to it) and I also added another JST connector to it to run some LED lights on the end of the arms.

Do you think if there was a bad connection or lost connection with one of the ESCs that the Thunder QQ board would have just shut down itself down?

 

[Vermiform]

Another thing. I replaced the xt60 with a Deans Ultra to match all of my batteries. This is my first flight with the male plus hot glued to the frame so I can just plug the battery into it. Think it may have vibrated apart from the female plug?

 

[Motopreserve]

Was it separated when you got to the crash site?

I agree with TStrike, more likely a cold solder point somewhere in the system. If that squid was bought from hobby king (or similar), good chance you may have a flaky solder point in there.

Have you been able to test all motors and ESCs? Do you smell burning anywhere on the MR?

Great looking farm!

 

[Vermiform]

Was it separated when you got to the crash site?

I agree with TStrike, more likely a cold solder point somewhere in the system. If that squid was bought from hobby king (or similar), good chance you may have a flaky solder point in there.

Have you been able to test all motors and ESCs? Do you smell burning anywhere on the MR?

Great looking farm!

Battery was ejected in crash so I will never know. No burning smell on ESCs and nothing felt hot at all, though I did not think to check thoroughly at the time.

I think next thing I will do is take the props off, start the motors and jiggle the squid around and see if I can make it repeat. It may give me something to do until the new PCB frame replacement gets here. Still need to finish tuning the gimbal as well so I want her flying again soon.

 

[Vermiform]

Great looking farm!

Thanks. It's my parents house but I live about 300 yards away on the other side of this property. My house is surrounded by "quad thirsty" trees and a power line so I always ride down the hill to my folks for my longer flights.

 

[Motopreserve]

Check all the connections, and as you said, see if you can shake it loose.

When you finally get back to the gimbal, see about buying or making an ND filter to help with and rule that out for the jello you're getting. And then see about the dampening.

Good luck with the tests!

 

[Vermiform]

Check all the connections, and as you said, see if you can shake it loose.

When you finally get back to the gimbal, see about buying or making an ND filter to help with and rule that out for the jello you're getting. And then see about the dampening.

Good luck with the tests!

Any leads on an ND filter for mobius with wide angle lense? Is there a way to drop shutter speed in the GUI mobius setup program?

 

[Motopreserve]

I don't have a möbius - so I can't give you details on that. But if they aren't pre-made, you could make one easily. There are some videos on YouTube, usually for the gopro, but same idea.

 

[Vermiform]

Jiggled the squid it was solid. Jiggled the battery lead and watched as it effortlessly popped away from the male Deans Ultra I have glued to the frame. One of the tension blades on the connector isn't doing it's job. 90% sure it just vibrated off, especially since the male end is mounted to the frame thus concentrating vibration there.

 

[Motopreserve]

At lest you found the culprit. I've never loved Deans, mostly because I've like the "cups" the XT60 have that makes tinning easy.

But I think the glue on frame deal ended up adding vibration, as you mention. I'm sure the silicone wire sucks up some of the vibes when the connectors are just free-floating.