Boeing initiated a request to the committee to form a task force to re-evaluate the acceptance criteria for conditioned cut wire (CCW) media. Currently AMS 2431 used “sketches”, which transferred from the cancelled specification MIL-S-13165. These pictures, in Table X, show examples of “acceptable, marginal, and unacceptable” media and are more than 30 plus years old and very subjective. It is one dimensional and can be easily misinterpreted by purchaser. Since 2008, many attempts had been made by various media suppliers and committee members to replace the table with an alternative acceptance criteria. Yet, there is no agreement among the suppliers with proposed solutions and the issue continues to be unresolved and forgotten.

Motion: To form a task-force to revisit this issue, Hali Diep (BOEING) and Walter Beach (Peening Technology) will be leading the team and sponsor the changes, along with other team members from media suppliers: Toyo-Seiko, Premier, Frohn and John Cammett (Consultant) to investigate and come up with a proposal to be presented at the next ASEC meeting in Troy, Mi. in May 2018. Motion was approved.

A webex meeting will convene on Nov 16 for open discussion. I'll report the results here.
It was decided that title of the specifications will add the word spherical and spherically where applicable through out the documents.

Example: AMS 2431/3

Was: Conditioned Carbon Steel Cut Wire Shot, Regular Hardness
(45 to 52 HRC)

Now: Spherically Conditioned Carbon Steel Cut Wire Shot, Regular Hardness (45 to 52HRC)

Rational: Spherically helps define the level of conditioning.
A simple approach would be to require circularity measurements to be applied to a specified number of particles. Computer-based image analysis has been available for decades. The basic equation for circularity (=4*pi*Area/Perimeter squared) gives a value of 1 for a perfect circle and lower values as circularity decreases. Specification could detail an allowed maximum % failing to reach a stated circularity value. The current "sketches" could be analysed to provide a starting point for the stated required minimum circularity. This approach would have the added advantage of being totally objective.
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