Cutting Tool Edge-Prep (Honing)

It is widely known that edge-prep, or honing, of cutting tool edges, can increase tool life by as much as 300%. Other benefits include lower operating temperatures and more efficient cutting operations due to less chipping. Surface improvement from the honing process may also yield further benefits.

For many years, tools have been honed by hand, and more recently, single-purpose brush honing equipment. While brush honing machines have been somewhat effective for the purpose of edge-prep, they are simply unable to offer the versatility and efficiency of batch processes using drag finishers.

When employed for cutting tool edge treatment, drag finishers allow for both edge-prep (honing) and polishing of coated and non-coated tools of various materials, with no need for extra equipment or fixturing. This multi-purpose machine approach saves on equipment, labor, and utility costs, as well as production floor space, making drag finishers ideal for use in production cells.

The use of drag finishers in cutting tool honing involves the following processes and procedures:

• Process media selection based on the material of the tool to be honed. More information on proper media is available on the Process Media section of this site. The single most important consideration in the media selection process is the desired degree of hone, which varies with the tool’s material, end-use of the tool (including materials the tool will cut), feed rate, and more. In many instances, a tool’s end-use may be unknown, in which case general guidelines will determine the best process media. More precise edge-prep specifications are within reach when the tool has a clear, specialized end-use.
• Proper fixturing based on the tool’s geometry: Ideal lead and trail angles for properly introducing the tool into the process media are important to the end result. Proper tool fixturing methods for drag finishing processes have been a topic of many discussions, and there are several ways to handle it. Please see our Tooling Section for more information. Typically, tools rotate on two axes during drag finishing processes. Additional special fixtures can add a third axis of rotation, powered through the main planetary drive system when attached. This third axis of rotation shortens process cycle times, resulting in more batches per shift, saving time and money. The number of fixtured tools per batch can directly effect the process results. Testing has shown that tools approaching 1/2″ in diameter can have a significant effect on the action of the process media. In this case, it is advantageous to fixture tools in every other position to increase the distance between the tools, mitigating the effects of the “wake” created in the media.
• Process parameters (entered into machine control panel): Our drag finishers allow you to set time cycle length, clockwise/counterclockwise cycle times within the overall time cycle, speed of the planetary head system, direction of travel, and depth of submersion into the process media. These all play another critical role in the final results. An optional second drive motor with independent speed and directional control of the heads is available. This comes in handy when your facility needs to process multiple tools of different sizes and geometry. Bel Air has a set of predetermined edge honing processes based on typical edge-prep requirements, and can provide these to you for items within the normal scope of edge preparation. For example, processing typical HSS end-mills, drills, and taps usually takes 20 minutes or less at an RPM of about 88 on the main planetary turret, with the machine’s direction of rotation reversing every 5 minutes. Larger diameter tools, as well as some carbide inserts, require lower RPM, with no change in head direction during the process, and require a finer grain abrasive media.
• Bel Air will process your samples free of charge. Upon your approval, we can provide a detailed quote for a complete turnkey system. Our delivery time is usually about 4 weeks, which is 1/3 of the average delivery times of our competitors. All of our systems are built in the USA, with service and spare parts just a phone call away.