Cutting Tool Polishing

Edge-prep, or the honing of cutting tool edges, is known to increase the life of cutting tools by 300% or more. Polishing of these cutting tools further serves to extend tool life, while also providing additional benefits to the end user.

Drag finishers, when employed for the use of cutting tool edge-treatment, allow for both edge-prep (honing) and polishing of coated and non-coated tools of various materials. Both honing and polishing can be done with only one machine, using the same fixturing. This multi-purpose machine approach serves to reduce equipment, labor and utility costs, while minimizing the required amount of production floor space. The versatility of drag finishers makes them ideal candidates for production cells.

Polishing non-coated tools is a very straightforward process, and only requires the most basic process media and tooling. In the case of coated tools, the ideal type of media for the process depends on the coating material used. Most types of tool coatings, by nature of the coating process, leave tiny “droplets” of the coating on the surfaces of tools. Results have shown that removing these droplets results in a smoother tool surface for a better cut, as well as a smoother flute area, which results in better chip evacuation, cooler temperatures, and the ability to run at a faster feed rate. Testing has shown that with the removal of the “droplets”, a small cavity is left behind on the surface of the tool. This cavity provides a “reservoir” for tool lubricant, allowing superior lubrication and cooling.

Cutting Tool, Polished after Coating

Before Polish 

Cutting Tool, Polished after Coating

After  Polish 

Tool honing end mill coating with droplets

TIN coated surface with droplets before polishing

Tool honing end mill coating with droplets eliminated

Droplets eliminated after polishing

The use of drag finishers for polishing involves the following processes and procedures:

  • Selection of process media based on the material to be polished: For more information on using proper media, please visit the Process Media section of this site. Selecting media for tool polishing is somewhat less difficult than selecting honing media, as there are fewer types of media designed for tool polishing. Polishing media can also process a much broader range of materials than honing media can.
  • Proper fixturing based on the geometry of the tool: Proper lead and trail angles are an important factor in presenting tools into the process media. Having the right articulation can go a long way in improving your end results. The fixturing of tools for the drag finishing process has been a topic of many discussions, and several methods of tooling are available for different needs. Please see our Tooling Section for more detailed information on this subject. On a typical drag finisher, tools spin around on two axes of rotation. Adding special fixtures powered by the machine’s main planetary drive system can provide a third axis of rotation. This additional rotation shortens time cycles, resulting in more batches per shift, as well as lower overall costs.
  • Process parameters are set in the machine’s control panel. These include total process time, clockwise and counterclockwise cycle times, speed of the planetary head system, direction of travel, and depth of submersion into the process media. Each parameter plays an important role in ensuring the best possible results. Bel Air can provide pre-determined processes based on typical polishing requirements for specific items, within the normal scope of edge-preparation. We also offer free sample processing of your tools.
  • Upon your approval of our sample processes, we can provide a full quote for a complete turn-key system that will allow you to reproduce the results. Our delivery times average four weeks, which is an estimated three times faster than most of our competitors. Our systems are always built in the USA, and both customer service and spare parts are just a phone call away.