The regrinding industry is experiencing change. Regrinding or resharpening of high-performance cutting tools and drills is a cost effective and environmentally friendly solution for extending the life of tools. Resharpening is offered by tool service providers across a wide range of manufacturing industries, including automotive, aerospace, medical, power generation and more.
Tool and cutter grinders are traditionally sold to cutting tool manufacturers and regrinding services, which make up the largest market. However, in-house CNC tool grinding has become increasingly attractive to manufacturers who use a sizable volume of tooling.
Resharpening is driven by environmental responsibility and the need to reduce overall tooling cost. The cost to recondition is generally lower than replacement cost, and it is commonly understood that the resharpening process is typically less than half the cost of producing a new tool. When one considers that an endmill can be reground at least three times, the numbers become even more compelling.
Tool service providers generally offer a high-quality, high precision resharpened tool and aim to provide performance near to original manufacturers specifications. However, the question becomes: When is it more attractive to in-source the resharpening of tools, and not only from a cost perspective?
A large tool consumer can potentially save cost by bringing reconditioning in-house. An added bonus is the additional flexibility, with turnaround time often being reduced. Therefore, it is not just the cost of the tools, but also the loss of production if the right tool is not available when required, that should be considered. Machine shops can run into overly long regrinding times, especially when they use unusual geometries. In addition, the machine shop does not need to carry excess inventory to provide back up.
Today's CNC tool grinders are easier to use than ever, but conversely, tools are more complex. While ANCA has introduced technology to easily automate mixed batch regrinding to ensure the process is easy and effective, any company new to tool grinding must still build up in-house expertise.
In any case, it is a big step, and not only because the investment into a tool and cutter grinder can easily be $300,000. There is also the cost of grinding wheels, workholding, coolant, utilities, floor space and, of course, an operator. A suitable CNC tool measuring machine will add to the set-up expense.
Evaluating the Economics
While an in-house tool and cutter grinding machine provides freedom to produce quickly and improve effectiveness in new ways, a machine shop that considers adding in-house tool grinding typically faces a difficult investment decision. As a result, cost of outsourcing and the investment of bringing tool resharpening in-house needs to be compared on a case by case basis.
The cost of regrinding in-house will depend on the utilization of a tool and cutter grinder. To approach the question in an objective way, first determine the hourly rate of the investment. This includes the cost of depreciation, interest, floor space, energy, maintenance and consumables cost. The cost of an operator will come into the equation based on one-, two- or three-shift operation, and if the machine has the capabilities to run unmanned.
Based on the hourly rate and the estimation of cycle time per tool reground, a manufacturer will be able to compare the base cost of in-house resharpening as opposed to outsourced services.
Once a shop has a cost comparison, it will be important to also evaluate the soft factors, such as:
- Cost of spares to maintain production while tools are reground
- Outsourced resharpening cost/tool x number of spindles needed in the machine shop
- Consider turnaround times/waiting times and possible cost of lost production in the event of a delay in regrinding service
- Tool quality
- Other processes required, such as edge preparation or coating
- Service and shipping costs.
Resharpening Made Easy
ANCA provides solutions to customers' problems and is traditionally working with industry partners like Zoller to develop integrated solutions.
Zoller and ANCA have developed what is designed to be a reliable and error-free data transfer system to automatically pre-set the regrinding process. This includes measurement of tool wear. The regrinding parameters can then be allocated to a corresponding pallet location when a tool loader is used. Once the tool is picked up by the loader and presented to the workholding device, ANCA Auto Tool Measurement (ATM) digitizes the tool. The ATM cycle has been developed to make regrinding a fast and simple operation. This cycle measures the most commonly required parameters for almost all tool types. A mixed batch of tools can automatically be loaded and reground.
ANCA Loadermate software can group the tools by tool type, required regrinding operations and infeeds based on the wear factor. The Loadermate allocation sets up a mixed batch of tools for unmanned operation.
ANCA offers a variety of automated regrinding solutions for mixed batches, such as collet loading (tool and collet getting changed together) or collet changing and RFID. With RFID, the required information is recorded at a programming station and the tool is coupled with the RFID tag. The machine picks up the tool, together with the RFID tag, scans the RFID and automatically calls up the grinding program. The RFID is parked while the tool gets loaded and reground.
With the ANCA RFID solution, customers can chaotically load tools into a loader pallet by creating an individual program for each tool. The tool position inside the pallet can be swapped with another tool anytime if a tool needs to be resharpened in a hurry.
The tool and cutter grinders can run the regrinding operation individually and unmanned. The duration of unmanned machine usage depends on the type of loader and the pallet capacity.
Authored by Andreas Sommer, ANCA Product Manager
For more information contact:
ANCA Inc.
31129 Century Drive
Wixom, MI 48393
248-926-4466
usainfo@anca.com
www.anca.com