May 2020 Issue
Toc

In a bit of a departure, Modern Abrasives & Deburring is turning its focus on deburring tools for punch press machines. The punching process frequently causes burrs on sheet metal parts. Removing them requires secondary deburring operations that are performed manually or with specialized equipment.

Wilson’s De-Burring Tool works by coining a small chamfer on the cut edge of the part with a ball assembly.

But when it comes to punching, fabricators have found they can accomplish a whole range of tasks, including deburring, before the parts even leave the machine. Deburring sheet metal parts directly on the punch press can improve part edge quality and reduce throughput time considerably.

Dan Caprio, punch press product manager for LVD Strippit, says, “As customers try and eliminate secondary operations, more and more are using deburring tools on the press. Otherwise, if the parts are cosmetic or being handled where sharp edges can cut someone, they have to use an automated deburring machine like a Time Saver or a Dyna-file or manual grinding, which are much more time consuming.

“Everyone from large OEMs to job shops is using these tools,” he adds. “They are a little tricky to program, which can be frustrating as you learn the tool, but they do work well. I recommend them to our customers who are looking for better secondary operation savings.”

A Special Tool

Major punch press tooling manufacturers Wilson Tool and Mate Precision Tooling offer deburring tools for turret-style punch presses. Typically around the $4,000 range, they are considered a specialty tool.

Mate Precision Tooling’s Rollerball Deburr tool pushes the burr away and creates a radius on the edge of the part.

Wilson Tool takes the rollerball approach with its deburring tool that basically follows the geometry of the punched part and forcibly reshapes the edge to remove the burr. The deburring process on a punch press does not remove the burr, but is more of a coining operation.

Available for thick turret-style or Trumpf-style punch presses, Wilson’s De-Burring Tool accurately and efficiently deburrs sharp edges on parts. It works by coining a small chamfer on the cut edge of the part with a ball assembly, flexibly moving in straight lines or arcs, including acute angles and very small radii. Wilson Tool’s design enables operators to save time by adjusting the ball pressure without disassembling the tool. For use on materials 0.8 mm to 5 mm thick, the ball assemblies are designed for extended tool life on a range of materials. They can be used to deburr nested parts and can be started anywhere on the edge of the part.

Another rollerball design is Mate Precision Tooling’s Rollerball Deburr tool for thick turret-style and Trumpf-style applications. This tool uses the programming capabilities of punch presses that can operate in the X-axis and Y-axis with the ram down. The tool pushes the burr away and creates a radius on the edge of the part. Using a special ball in the upper and lower part of the tool, every possible part contour can be processed, even small corners. The tool can be used with any thickness in mild steel, stainless steel and aluminum.

“Everyone from large OEMs to job shops is using these tools. They are a little tricky to program, which can be frustrating as you learn the tool, but they do work well.”
Dan Caprio, punch press product manager, LVD Strippit

From The Source

In addition to tooling manufacturers’ offerings, OEMs including Trumpf and Amada offer deburring tools for punch presses as well. Trumpf offers various options. The roller deburring tool is mainly used for simple, large contours. The roller geometry is adjusted to the material thickness to ensure burrs are neatly flattened. Interchangeable rollers are available for various material gauges.

View the video to see how Mate Precision Tooling’s Rollerball Deburr tool removes burrs from the material.

The deburring MultiTool is used for cutouts with a travel radius smaller than 20 mm for deburring small inner contours. The burr is processed in single-stroke or nibbling mode using the three integrated embossing inserts in the die. The punched edges are then rounded off with the roller deburring tool and almost burr-free parts can be achieved, making the tool particularly suited for visible edges on parts.

By modifying the roller contour to the altered burr and the width of the separation gap, a high-quality result is ensured in all material thickness ranges. Die inserts are adjusted to the material thickness to ensure burrs are neatly flattened. The range of deburring geometries increases flexibility.

Trumpf’s roller deburring tool is for simple, large contours. The roller geometry is adjusted to the material thickness to ensure burrs are neatly flattened.

The ball deburring tool is for deburring small and large contours. It is especially suited for deburring complex holes and the corners of parts. The burr is compressed between the two balls in the punch and die, which causes a chamfer to develop on the upper and lower side of the material. Deburring is also possible near formed sections thanks to the beveled punch head. It offers a high degree of flexibility based on deburring different size and complex contours using just one tool.

Accomplishing the same deburring task but without the ball technology, Amada’s deburring tool utilizes a chamfered edge die where the burred edge of the part is pressed flat. The tool can be made to match any parting tool size.

Deburring tools for turret-style punch presses, typically around the $4,000 range, are considered a specialty tool.

Burr Problems

Burrs can create all sorts of problems. Negatives include safety issues where the sharp edges result in hazardous handling for operators; increased stress during operation, resulting in reduction of resistance to fractures and fatigue; susceptibility to corrosion; and interference when applying finishing processes like powder coating or electroplating.

Amada’s deburring tool utilizes a chamfered edge die where the burred edge of the part is pressed flat. The tool can be made to match any parting tool size.

Of course, not all fabricators are in the position to purchase new tooling. There are factors they can still use to ensure they are getting the best possible edge quality when punching.

  • Correct die clearance. If the die clearance is increased, the part ends up with more of a burr.
  • Sharp tooling. Dull tooling is not sharp enough to cut metal; it just breaks through and rolls over the edge, creating more of a burr.
  • Punch and die alignment. The cut edge will be inconsistent if the alignment of the punch and die isn’t the same.