TechTalk #3 - Essential Tools

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Three Essential Tools Every Pro Should Know

Vacuum dies, air eject tools and plunger tools are used every day in this business. But how much do you really know about these "tools of the trade?" Here's a brief overview of each.


Vacuum Dies

Vacuum dies are used to remove stand-alone parts from the web. Anytime there is an island in the middle of a part that needs removal, a vacuum die should be considered. These factors can help you decide when a vacuum die should be used:


  1. The size of the part to be removed must be smaller than the journal, as the part will be removed through the journal.
  2. Consider the number of parts to be removed with the vacuum. If too many holes are drilled into the tool, it can loose integrity and performance.
  3. You will need a special vacuum journal block to remove the pieces from the tool.
  4. Since vacuum dies are made with inserts, you should examine if there are any intersecting blades. Also note the proximity of other blades on the tool. Remember, you'll need enough room to put inserts into the die.

Air Eject Tools

Air eject tools are used to ensure that the cavity on the die does not pack up with debris and break. In rare instances they can be used to remove the waste in an island tool, but never 100% of the time. The following should be considered when ordering an air eject tool:


  1. The numbers of air eject holes in the tool. Just like with the vacuum, you do not want to destroy the integrity of the tool.
  2. You must be able to maintain 100psi at the die. You must consider not only the ability of your air compressor to get to 100psi, but also the size of your holding tank and how fast your compressor can recover. Again, this will depend on the number of holes and how fast you intend to run the tool.
  3. The type of material being cut is another consideration. For example, if you are trying to eject an open cell foam, you will not be successful, as the air has very little to push against.
  4. Whenever possible it is best to run the air eject portion of your part on a separate tool. This allows you to run the web up after cutting and avoid ejecting while the die is cutting against the anvil.

Plunger Tools

Plunger tools are used for the same things as air eject tools. The advantage of plungers is that you do not have to worry about the air pressure as the ejection is done mechanically with a spring. Consider the following when ordering a plunger tool:


  1. The size of the part to be ejected. The smallest dimension cannot be less than .200". You must have room to drill and tap for the plunger to be inserted.
  2. The center-to-center dimension around the tool. The larger the part to be ejected means the larger the plunger that you'll use. There must be enough room as you drill and tap to ensure the holes do not run into one another
  3. The type of material to be ejected is also critical. For example, highly compressible foam would not be a good candidate.
  4. Finally, similar to air eject, it is best to separate the plunger into a separate tool. This gives the springs enough dwell time to work properly.

The proper tool and its uses are important to understand, especially when you know that the right tool will improve your overall bottom line.


If you have additional questions or thoughts about how force affects your applications, we invite you to contact the technical team at Wilson. Click here to contact Wilson Manufacturing