Every toolholding system on the market today started as a solution to a problem. Now, manufacturers have access to a comprehensive range of products that overcome every challenge, from the instability of long tool overhangs to the high temperature issues of heat-shrink holders. But when it came to the development of the ER collet toolholding system – now an industry standard and the most widely used in metalcutting – the problem manufacturers faced was one central to all toolholding, and that was precision.
Before collet systems, most manufacturers relied almost exclusively on end mill holders that clamped tools using set screws. When it comes to keeping tools in holders, set screws tend to do the job – if tightened correctly, and if used in more conventional machining applications. To center the tool and achieve acceptably low runout, however, “correctly” becomes “expertly.” Likewise, while these holders have high rigidity, it comes at the cost of flexibility, as they accommodate only tools of a single diameter and those with flats ground in their shanks.
To overcome these issues, the collet system was developed in the 1960s. A clever solution that uses symmetrically cut slots in a tapered body, the collets gripped a tool’s complete shank circumference for far greater concentricity and considerably less runout. The only drawback at this point was a tendency for the collet to get stuck inside its holder, a situation that required users to hammer tools out of the expensive holders.
Enter Firma Fritz Weber, the company that would become today’s REGO-FIX. Named for its founder, Fritz Weber, the company’s solution to the collet ease-of-use problem was simple and elegant: a groove. A collet-retaining lip inside the nut fits inside a groove on the collet, which means that when a user unscrews the nut, the collet is removed from the holder along with it. Further refinements to the design of collets and nuts improved the flexibility of the system as well, which uses a millimeter of give to accommodate a wider range of tool diameters.
This system, which the company named “ER,” was patented in Zurich in 1972, and two years later, the patent was published. This didn’t mean the end of innovations from Fritz Weber and REGO-FIX, naturally – even after the success of the ER system, Weber’s company worked tirelessly to improve the design of clamping nuts and the overall system, pushing precision further with every iteration. And 20 years after its patent was published, REGO-FIX made the ER concept even more widely available by working with Deutsches Institut für Normung (DIN), or the German Institute for Standardization, to have the system recognized as an official DIN 6499 standard.
Even after literally setting the standard however, REGO-FIX continued its relentless pursuit of precision. The remarkable ≤0.0004″ (10 µm) runout made possible by the ER collet was reduced to ≤0.0002″ (5 µm) with the Ultra Precision (UP) line of ER collets, while company’s micRun® and powRgrip® systems further reduce that amount to ≤0.0001″ (3 µm) at 3xD tool ratio. REGO-FIX continues setting new standards and developing new tooling and toolholding innovations that help manufacturers push precision machining beyond its limits to build the products of the future.