Spacing of Perforations
Spacing for large perforations will be designated by either
Centers of Perforations, or by the Open area required.
Spacing for small perforations will be designated by either
Centers, or Open area, or if more practical, by the Number
of Perforations to the Square Inch.
Pattern of Perforations
Unfinished End Pattern ĘC As a result of tool design, some
specifications of staggered pattern perforations yield a pattern
that appears incomplete at both ends of the sheet. This is an
Finished End Pattern ĘC As a result of tool design, some
specifications of staggered pattern perforations yield a
completed pattern on both ends of the plate.
Staggered Perforations, both Round and Square ĘC The
pattern stagger is normally in the short dimension of the sheet.
Holes in a straight row pattern are normally parallel to long
dimension of sheet.
Slotted Perforations ĘC Slots can be furnished parallel with
either the length or width of the sheet in most cases.
Perforated stock size sheets and plates.
The long side of a sheet will be supplied with minimum
margins. The short side of a sheet will have either minimum
margins or no margins.
Sheets and plates resheared after perforating.
Special margins are available, but they must carry a tolerance
within the limits of the perforating tool.
Unfinished end pattern is standard in the industry.