It's just a burr from manufacturing that is not removed. I had the same thing happen to me....was not fun flying around for 6 minutes on three-quarter throttle.
I just cleaned it off with a real fine fine and even finer emery after. Did it at the field. No biggie....was flying in 15 minutes. It seems many have this problem.

Ed...where do you fly?

I fly in Farmington.
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