In a previous article about using crimp lock perforators we show you how to use that tool to effectively run certain difficult saddle stitching jobs with a little less hassle. Today we’re going to show you how to automatically do a letter fold with a loose insert tucked inside, as shown in the photo at right. Technically speaking, we are producing a 4-panel roll fold in two sections. Then we do some trimming to produce the desired result. You can see the full layout of the folding machine operation in photo 4 below.