Graphic Design & Printing Technology
preceding fold by changing the direction of the sheet 90o before the second
fold is made.
Other type of folds include letter fold, accordion fold, French fold, barrel fold,
gate fold and short fold.
Types of folders:There are two type of folding equipments - Knife folder and
buckle folder. Some equipments use a combination of these two configurations.
Knife folder:It is a folding device that
use a metal blade to force a sheet through
a set of folding rollers to create a fold.
Fold rollers are metal rolls that transport
a sheet through a folder. The paper is fed
into the folding unit with moving tapes
or belt. Side guide keeps the paper aligned
and fold guides stop the paper in position
above the nip of a fold roller. Then the
knife is lowered and it pushes the paper
into the rotating fold rollers that crease the sheet. If additional folds are required,
one or more folding units are added and folded sheets are added to them
automatically. Knife folders are more accurate in producing right-angle fold.
Heavier-weight papers perform well on knife folders.
Buckle Folders: It is folding device that use a fold plate to force a sheet to
buckles so the sheet can be pulled through a set of folding rollers. The buckle
folder uses tapes or belts to carry a sheet of paper. The sheet is carried towards
a fold plate consisting of two metal plates positioned at a slight incline above
the drive and the fold rollers. The drive feeds the sheet into the fold plate and
continues to move the sheet after it hits the stop guage at the top of the fold
plate assembly. The sheet buckles downwards, and the fold rollers catch them
in a predetermined spot. The rollers grab the sheet at the buckle, pull the sheet