c. Another threading system is the "loop" type. In this system, the film
is threaded in a loop around the rollers and only the film base touches the
rollers (fig 1-3).
Loop type threading
d. Leaderless Machines.
These machines do not require threading with a
leader, but transport the film through the machine by another means.
transport method is a double row of rollers that are closely spaced to each
other, and to the opposing row. The film is first spliced to a stiffening tab,
usually called a "bullet." The bullet with the film attached is inserted into
the machine and is transported between the rows of rollers and through the
More will be said about this type of transport system
later (fig 1-4).