Home Forums General Discussion Specifications "Edge Type: Number 1" in J442

J442 specifies a number 1 edge on the 3" side of Almen strips. Can anyone tell me what industry spec governs exactly what consitutes an acceptable number 1 edge?

Thanks,
John Z.

John,
The following link to "learning on line" at our web site shows the types of edges.

http://www.shotpeener.com/learning/types_of_edges.pdf

Earlier versions of SAE J442 referred to square Edge #1 but some strips were being made with round edge #1 so we (I chair the Surface Enhancement Division of SAE, custodian for SAE J442 and other peening specifications) decided to drop the square and round requirements and just state "edge #1".

Jack:

Thanks ... I had already found this on your site, and it is the best document I have found so far.

But where did it originate? Certainly, somewhere back in time, there was an official designation for this. Otherwise, who deterimines whether an edge #1 (or any other edge) is "good" or "bad", and how would you be able to show compliance? MIL-S-13165 requires the number 1 square edge, so this requirement has been around for quite awhile. Surely an industry spec ... or perhaps some sort of steel rolling mill bible ... spells this out.

John Z.