minton wrote:I'm hearing some great points/questions to address but where is the data that addresses our questions? Any ideas??
There is the chemical stripper issue, what strippers are a NO, NO? The inspection process leading to a yellow tagged gear leg, and when is re shot peening requirered/commended and probably more.
I hope someone has this material available to the forum.
Well, there you go! Good information. I'll bet we'll all be looking at the gear a little closer.
Is there any shot peening info out there in regard to being required for recertification??? That seems to be my sticking point when I see "Overhauled", "Yellow Tagged" or "8130 Tagged" parts offered for sale.
OBTW: I still have the "How do we know?" question on embrittlement. Any NDT testing available?
I found an interesting article on hydrogen embrittlement by the "Corrosion Doctors" (Google it). In a small part of the article it says that if the metal is removed from the source of Hydrogen Sulfide exposure, over time that material will defuse from the metal. Seems to be a sub atomic issue. Hum? I wonder??
I have my gear out now for some restoration work for the airplane. I was going to put some spare gear in, however, given a recent occurrence with another airplane, I will be selling my spare gear and putting my original gear back under my airplane.
What is the preferred blast media to strip? I have some 80-grit glass bead media, and I also see that walnut shells are a little coarser grit according to the label at Harbor Freight.
My IA didn’t have strong feelings either way, but I suspect walnut shells will be a little safer.
Also mentioned is the need to “shot peen” the gear when refurbishing it: The shot peen specification is to be Almen intensity of 0.012 to 0.016 with 330 steel shot
'53 B-model N146YS SN:25713
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