Weldon-Flat Tools in a Precision Toolholder

Systems for locking end mills in place within a shrink-fit or hydraulic expansion toolholder, so that there is no danger of the tool pulling out during high-force cuts using a toolholder of this type, often require the shank of the tool to be modified for clamping.

However, there is one standard class of tools that already has a shank modified for clamping: tools with Weldon flats.

Schunk recently introduced a system that makes use of the Weldon flat for clamping during high-force milling with a precision holder. The system, seen here as it was displayed at this year’s IMTS, is based on the company’s Tendo line of hydraulic-expansion toolholders. As seen in this model, a metal sleeve holds the tool, clamping on the Weldon flat. That sleeve then provides the surface for the screw that locks the tool in the holder for the high-force milling typical of aerospace materials such as titanium and Inconel.