Static Thrust Test - Am I pushing too much??

[lunarair]

Setup for a static thrust test with my X650 quad today, holding the craft at hand pointing outward, WKM changed to manual mode and pull full throttle ...... 2 plastic arms snap off and break away in 1 second... :upset:

I notice the breakage position are all the same at the plastic mounts where it connects to the motors. Seems no point with all the carbon fibre arm only to find it breaks at the weakest link (The motor mounts)


Or am I doing it the WRONG way?? (I thought that's how real aircraft do engine run up test too~~~)

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Chit

 

[Big Duke Six]

I don't think you're necessarily doing it the wrong way. It would be nice if the frame could take that kind of stress, and I think it should. But apparently the reality is that in the name of weight savings, they have designed the mounts only to a certain strength. One could argue that the quad would never see the kind of stress you put on it, but I feel it should be able to handle it. I don't see any difference between asking full static power from the motors and a maximum thrust climb. Just know that that would come with a weight penalty of course, but this doesn't say much for the integrity of the frame. Have you contacted the manufacturer?

Big Duke Six

 

[lunarair]

Or better "Cost saving"

Typical Made in China mentality haha.

I did not attempt to contact the manufacturer because I wasn't using the default configuration. (4s vs 3s, 950kv vs 980kv, 1147 vs 1047 prop)

As a conclusion, I suppose these quads are not to be flown under manual thrust with full power from a 4s cell.