Non-Destructive Inspection (NDI) Methods for plastics.

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After reading a thread about a guy having a prop come apart in flight, resulting in his loss of his P1 Quad, I thought I would make a thread about something I've thought up for inspecting our Props and the shell itself. I'll have to try it out to see if it will work on metal bits however, we are primarily going to focus on the plastic pieces since there are so many of them on my P2V+ V3 and all of our Quads, unless using an aftermarket Prop, will benefit.

I've been building computer for a good many years. I've been using water cooling for much of that time. For those true geeks among us, my very first water cooling system used an A/C radiator from a Chevy Chevette and a run of the mill garden fountain pump to provide circulation. A custom milled CPU block and pieced together retention system saw my old AMD K6-2 400 CPU hit 450MHz. HUGE performance gains back in the day!

So applying some basic knowledge from the evolution of computers and water cooling, I think I'm going to give this a shot to see what I can come up with for NDI methods. In particular, we would us what's called Dye Penetrate Inspection methods. See this link for more information on the methodology.

I'm thinking of using a non-conductive, UV reactive fluid like this.

A single 32oz bottle would last a good, long time. As long as the solution is kept in a cool, dark space, it will last for years. As long as it isn't milky looking, as long as it is clear, it is a usable solution. I've had some of this stuff last for 10 years.

Put said fluid in a spray bottle and lightly mist Props. Then, using a Black Light I currently have, look for cracks in the props. Especially after any type of prop strike whether that would be insects while flying or, prop strikes due to roll overs/objects on the ground upon landing. It would be a simple thing to soak the prop and then, flex it by hand to get the fluid into any cracks or hairline fractures. My years of aviation experience has shown this to be a very effective method for inspecting parts. However, I don't care to purchase the very expensive fluids used in Aviation testing.

I have the fluid already and, as mentioned, the black light. All I would need is for some folks to mail me their damaged/high time blades so I can produce a usable inspection method and publish my results here. Even props with stripped out hubs would be beneficial because I could then induce cracks intentionally and then, use such props to develop a good, reproducible inspection method.

So what say you? Anyone interested?
 
I'm interested to see what a hairline crack would look like using this method.
 
Although interested on the ability to inspect via NDE I am not sure of this method. Would suggest you not use the liquid penetrant on the blades. Some penetrants, cleaners or associated developers may not be compatible with the plastic and could cause unexpected issues such as degrading plastic.
 

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