PCD Tool Sharpening Guide

PCD cutting tools can often be sharpened several times, but successful servicing depends on the condition of the cutting edges, the remaining PCD, the tool body and the dimensions that must be maintained.

At Prima Tooling, each PCD tool is inspected and measured before sharpening on our Vollmer QXD erosion machines. After servicing, the tool is measured again to confirm its finished geometry and dimensions, then dynamically balanced before being returned to the customer.

This guide explains how PCD tools are inspected, sharpened, measured and balanced, as well as the practical limits of servicing and when retipping or replacement becomes the more economical option.

This guide focuses specifically on PCD tooling. Prima Tooling also sharpens and reconditions solid-carbide, TCT and HSS tooling using processes appropriate to each cutting material.

Before any sharpening work begins, each PCD tool is inspected to establish whether it can be serviced economically and safely.

We check the PCD cutting tips for wear, chips and cracks, along with the condition of the tip seating and the surrounding tool body. Minor edge chips can often be removed during normal servicing. Where a tip is badly chipped or cracked, replacing the individual tip may be more economical than heavily eroding the complete tool.

Excessive erosion can reduce the cutting diameter and remove a significant amount of usable PCD, shortening the tool’s remaining service life. Retipping may therefore be recommended where maintaining the original diameter is important.

A damaged PCD tip can normally be replaced only when its seating and the surrounding tool body remain in serviceable condition. Where the tool body or tip seating has been badly damaged, the tool is not suitable for retipping and must be replaced.

Before sharpening, the tool is measured to establish its existing condition and provide a reference for the finished tool.

Depending on the tool design, we record dimensions such as cutting diameter, cutting width, profile, runout and the amount of PCD remaining. Inspection and measurement are carried out using our Walter Helicheck and Zoller presetter.

Recording these dimensions is especially important where the finished diameter is critical, the tool forms part of a matched set or the customer uses CNC diameter compensation.

Customers should advise us of any minimum allowable diameter, cutting width or profile limits before servicing begins.

PCD cutting edges are sharpened on our Vollmer QXD erosion machines. The tool is set up according to its existing geometry, cutting-edge condition and the dimensions that must be maintained.

During servicing, a controlled amount of material is removed from the PCD cutting edges to restore sharpness and remove normal wear or minor chips. The amount removed is kept to the practical minimum so that unnecessary loss of cutting diameter and usable PCD is avoided.

Where several cutting edges are present, they must be serviced consistently so that the finished tool runs correctly and each edge contributes evenly during machining.

The finished geometry will depend on the original tool design, previous sharpening, the amount of damage and the remaining PCD. A heavily worn or chipped tool may require more material removal than a tool sent for routine servicing.

After erosion, the tool is measured again using our Walter Helicheck and Zoller presetter. This confirms the finished cutting diameter, cutting width, profile and runout before the tool is returned.

Comparing the measurements taken before and after servicing allows us to confirm how much material has been removed and whether the finished tool remains within the required limits.

Where CNC diameter compensation is used, or where the finished size is otherwise important, the serviced dimensions are recorded and reported to the customer so that the appropriate machine offsets can be applied.

Tools forming part of a matched set require particular care because differences in diameter, profile or cutting width may affect the finished component.

After final measurement, every serviced rotary tool is dynamically balanced on our Haimer Tool Dynamic balancing machine.

Sharpening, retipping and repair can slightly alter the distribution of mass around a tool. Dynamic balancing checks the completed tool and allows any imbalance to be corrected before it is returned to the customer.

Correct balance is particularly important for tools operating at high spindle speeds, where excessive imbalance may contribute to vibration, poor surface finish, uneven cutting-edge wear and additional load on the machine spindle.

Balancing forms part of our standard servicing process rather than being treated as an optional final check.

The number of times a PCD tool can be sharpened depends on the original tip size, tool geometry, amount removed during each service and whether the cutting edges suffer damage between services.

Routine servicing removes less PCD than correcting severe wear or chipped cutting edges. Sending a tool for sharpening before it becomes badly worn therefore helps preserve its cutting diameter and extend its total service life.

Prima Tooling will normally continue sharpening a tool while approximately 1 mm of serviceable PCD remains, provided the cutting tips, brazed joints, tip seatings and tool body remain in suitable condition.

This is a practical guide rather than a fixed limit. Some tool designs or applications may require retipping or replacement sooner, particularly where the cutting diameter, profile or cutting width must remain within a narrow tolerance.

Retipping may be recommended when one or more PCD cutting tips are too badly chipped or cracked to restore economically by normal erosion.

Although severe damage can sometimes be removed by sharpening the tool more heavily, this may reduce the cutting diameter substantially and remove a large amount of otherwise usable PCD from the remaining cutting edges. In these circumstances, replacing the damaged tip can preserve more of the tool’s original dimensions and remaining service life.

Some customers also choose to have tools retipped rather than repeatedly sharpened where maintaining the original cutting diameter is especially important.

Retipping is possible only when the tip seating and surrounding tool body remain in good condition. If the seating or tool body has been damaged, the tool may no longer be safe or economical to repair and will need to be replaced.

Not every worn or damaged PCD tool can be sharpened or retipped safely and economically.

Replacement may be necessary where the tool body is cracked, distorted or badly damaged, where a PCD tip seating has been destroyed, or where insufficient cutting material remains to restore the required geometry.

A tool may also have reached the end of its practical service life where repeated sharpening has reduced the cutting diameter, cutting width or profile beyond the customer’s usable limits.

Every tool is assessed individually. Where further servicing is not recommended, Prima Tooling will explain the reason and advise whether a replacement tool, modified design or newly manufactured bespoke cutter would be the most practical solution.

Providing accurate application and dimensional information helps us assess the tool correctly and avoid unnecessary changes to critical features.

Please tell us when the finished cutting diameter, cutting width or profile must remain within a particular limit. We also need to know when the tool forms part of a matched set, when CNC diameter compensation is being used or when an original drawing or tool specification is available.

Details of the material being machined, spindle speed, feed rate, cutting depth and any recurring tool damage can also help identify whether changes to the tool design or machining conditions should be considered.

To arrange an inspection or discuss a servicing requirement, visit our PCD sharpening, retipping and repair service.

The most economical option depends on the condition of the PCD cutting edges, the remaining tip material, the tool body and the dimensions that must be maintained.

Routine sharpening is normally the best option where wear or edge damage is limited. Retipping may be more practical where a cutting tip is badly damaged or where preserving the original cutting diameter is important. Replacement is required where the tool body or tip seating is no longer serviceable.

Prima Tooling can inspect existing tooling and recommend sharpening, retipping, repair or replacement based on its actual condition and the customer’s machining requirements.

Where an existing tool cannot be repaired, we can also manufacture a replacement or bespoke cutting tool to suit the application.