Page 6: Frequent Tape Jams

There are several things to check if the tape is frequently jamming.

Jamming is generally due to one of the following reasons:
  1. Glue build up or worn moistening brushes
  2. Lower tape plate out of adjustment
  3. Incorrect or missing moistening brushes
  4. Incorrect upper shear adjustment
  5. Missing or bent upper tape plate / tape guides not being used

A. Glue Build Up or Worn Moistening Brushes

The moistening brushes act to not only moisten the tape, but to create a gap between the pressure plate assembly and the lower tape plate. If the brushes have a glue build up, they tend to flatten down, reducing the gap. The tape then gets stuck just before the moistening brushes under the pressure plate.

  1. First, inspect the brushes. If they are worn down to the level of the lower tape plate (the plate comes out and stops just before the moistening brushes), replace the brushes (M100MB3x [Ref. PW107AK]).
  2. If they have a heavy glue build up, wash them out with warm, soapy water and see if the jamming problem goes away.

B. Lower Tape Plate Out of Adjustment

  1. Just behind the moistening brushes, you’ll see the leading edge of the lower tape plate. Right where the lower tape plate and pressure plate meet, there is a rod with two brass rollers on it.
  2. There must be a sufficient gap between the pressure plate and lower tape plate. You can easily open the gap with a regular screw driver.
  3. Place the edge of the screw driver under the pressure plate and over the lower tape plate right near each brass roller, and gently twist the screw driver.
  4. This should open some space between these two parts, allowing the tape clearance.

C. Incorrect or Missing Moistening Brushes

Surprisingly, we find many tape machiens missing one moistening brush or find that over the years, someone has replaced the original brushes with something else. This can easily create tape jams.

Correct brush measurements: 3.5″ long x 2.5″ high x 0.25″ deep
Black nylon bristle, two brushes per machine.

D. Incorrect Upper Shear Adjustment

Tape jams can occur if the upper shear has been incorrectly adjusted. The travel height of the shear is adjusted when the lower feed wheel is adjusted. If you adjust the lower feed wheel, check to make sure the upper shear goes up high enough to allow the tape to travel underneath. See “Tape Cutting, Section D” for the correct procedure if you have made any adjustments to the lower feed wheel.

E. Bent or Missing Upper Tape Plate

  1. Check the upper tape plate. It is located on the lower tape plate around the upper feed wheel.
  2. The upper tape plate should slide in and out easily. If it is bent and cannot slide easily, it will bind the tape and cause jams.
  3. If it is bent, order a new one.
  4. Check to make sure that the operator is using the tape guides, located in the tape basket area. They must be correctly set to the width of the tape you are using.
  5. If the guides are not being used, the tape will skew as it is dispensed, causing tape jams.

If you can’t find the answers here, then please feel free to call us at
Email for assistance.