This is another method of leaving the individual circuits in a mother panel format. Scoring machines tend to either work by edge or pin location. Ours is the latter and uses a pair of pins for its registration.

A V shaped groove is cut top and bottom which then allows the circuits to be broken out of there panel. A small amount of the outer edges of the boards is removed in the process, which would include any fine track running along the edge.

Another point of warning is that the flexing during the breaking of the panel can lead to failures with surface mount components. This process is not recommended for that type of board unless you use one of the special machines to break the boards out without stress.

Although any normal laminate can be used the CEM or FR2/paper laminates are preferable to epoxy FR4. Main reasons are a cleaner final edge and reduced component damage resulting from the lower forces required to separate the panels.

For large batches of small PCBs this scoring if regularly the most cost effective profiling option.