TABLE OF CONTENTS Finger stops, or primary stops as they are sometimes called, are used in dies with two or more stations. They register the strip for performing operations prior to strip engagement by the automatic stop or roll feed. The number of finger stops used depends upon the number of stations in the die. For hand feeding, it is always one less than the total number of stations. For automatic feeding, only one finger stop is required. Finger stops are made of cold-rolled steel, cyanide-hardened.
In the early days of press work, numerous vertically acting primary stops were used. The hazard of placing fingers between upper and lower die members caused them to fall into disrepute. Presently, almost the only finger stops used in modern plants are the horizontal types to be described.
This chapter illustrates numerous standardized finger stops; they are fully tabulated to help the designer select the right one for the conditions encountered. Machining data are given for accompanying front spacers. In addition, general rules are outlined to help in the correct selection and application of these die components. This further explains Step 8 in Chapter 5 Fourteen Steps to Design a Die.
Taken together, the illustrations in Figure 13.1 and Figure 13.2 explain the operation of a typical finger stop. As shown in this plan view of a twostation die, two holes are pierced at the first station, and the blank is removed from the strip at the second station.
