Take A $42,000 Bite Out of Operating Costs: Eliminate Nibbling

As fabricators look for ways to improve manufacturing efficiency, some processes are more obvious than others. One of the most inefficient, frequently overlooked fabrication techniques is nibbling large holes with a small punch. While nibbling works, this process causes problems that affect both the machine and the workpiece, such as:

  • Punching debris that damages turret bores

    Nibbled Hole

  • Increased production time from the numerous hits
  • Excessive tool wear that requires more frequent maintenance and replacement
  • Machine wear and tear
  • Rough or scalloped edges on the workpiece that require secondary operations.

This last problem—post-punch rework—is common in sheet metal fabrication shops, but it doesn’t have to be this way. The rework can be eliminated with a simple change in the punching process and a minor investment in tooling. Mate’s Sales Engineers have the ability to identify these opportunities to bring significant savings to your manufacturing process. Let’s take a look at the following example.


A central Mexico manufacturer punched large circles with three different diameters using a nibbling process. The resulting parts had a highly rough finish that needed to be ground manually after the holes were punched. Two workers dedicated their entire work shifts to correcting this defect. Observing this during a visit to this customer’s plant, David Inzunza, Mate Sales Engineer for central Mexico, spoke to the engineer in charge of this operation.

Most turret presses include an auto-index station that rotates a punch and die to any designated angle dictated by the machine program. David recommended the use of Mate’s Tri-Radius tool, which is a punch with three different radii. The tri-radius can create three different diameters using a D auto-index station in a thick turret machine or Size 2 tooling in a Trumpf punch press. Mate designs and manufactures this tooling with the three radii the customer specifies.

The result is a surprisingly clean circle. The need for secondary grinding operations is eliminated, and the personnel dedicated to this activity can perform other functions. In addition, there is a significant savings in grinding supplies.


Hole Punched Using Tri-Radius Tool

The company now benefits from a much lower cost of operation due to this simple change in tooling. By eliminating the grinding operation and moving them to new roles, they gained the equivalent of two operators’ labor reused for other profitable work.

  • Lower cost of labor: since they did not need to hire two additional staff, they saved $30,240
  • Cost of grinding consumables: 8 flaps/day at $3each x 2 operators = $12,096

Total Benefit by Changing to a Tri-Radius Tool: $42,336