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Questionable 4130

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user 38

Well-Known Member
Aug 29, 2006
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Recently I ordered and picked up from a well known and local Experimental aircraft parts supplier 1 inch x .035 wall 4130. I did not pay attention at the time I picked it up, but when I got to working with it, I noticed that there was none of that white or yellow writing verifying its size and grade. I didnt think much of it until I began to remove the mill scale when I found pitting over the outside surface, I would estimate .0005 or better deep. 80 grit emery cloth would not readily remove it. Today, I stopped by the same store and mentioned the what I had found and was told that was probably some Chinese steel. He then went in back and came out with some 3/8 "4130" that a customer had returned that still had the open seam over about a 12 inch length.
I am not sure what is going on or even if there should be a concern over what I have seen with my last purchase. Has anyone seen this before? Anyone talking about chinese 4130? I dont want to start a panic, so this is more inquiry than statement of fact.

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