A comment on a previous ballot on determining the mass centroid as detailed in 7.4.1 and note 10 of C140, noted that portions of Note 10, which covers determination of mass centroid, contains some mandatory language. It was further noted that while ASTM C140 does mandate that the mass centroid needs to be aligned with the center of thrust of the test machine, the procedure for determining center of mass is in that non-mandatory note.
The task group discussed whether or not that procedure should remain in the note. While the task group could envision several ways to determine the mass centroid, the most practical and simple method is the procedure detailed in the note. This ballot item proposes to move the bulk of the procedure into the mandatory requirements of C140 and put only explanatory information in the note.