Rolling Margin

If you are talking specifically about steel, this has already been discussed in this thread:

http://cr4.globalspec.com/thread/8436/Rolling-Margin-for-Reinforcement-Steel

In this thread, it also explains that rolling margin is the "mass per unit length."

Jaxy, I read the thread you linked to, but my interpretation of it was different from yours. Rolling margin isn't "weight per unit length", it is the margin for error that you can expect on the acheived weight per unit length due to worn dies or deliberate adjustment of the settings at the rolling plant.

Frank

I was going off of comment #10. I didn't look too far into it. Whoever this person posing the question is, they can read into it further.