The efficiency of the Haimer Safe-Lock system in roughing and heavy duty machining operations has been proved by Heller in an extensive milling test with shrink fit chucks. The machining test was conducted using a four axis Heller H 5000 with a gear unit and HSK-A100 spindle, using different 25mm diameter end mills to mill full slots into a titanium plate. The tools were clamped into reinforced shrink fit chucks to simulate holder conditions used in the aerospace industry. Then the application was run again with a reduced spindle taper interface, using a HSK 63 instead of HSK 100, with less rigid 5-axis gear driven spindle and a less stable diagonally fixtured workpiece.
By increasing the full slotting depth to ap = 2 x D, with the Safe-Lock system the tool was able to complete the slotting process with complete reliability even in heavy machining conditions, avoiding the breaking of the tool as a result of increased cutting forces. Heller ultimately noticed that the patented Haimer Safe-Lock system in addition to frictional clamping forces prevents the tool pull-out, by having the same helix pattern as the tool. This way the company proved the potential of the Safe-Lock in the shrinking technology with HSK-A100, and the sample machining on Ti-6AI-AV was carried out various further times, proving the previous limit of 1 x D = 25 mm full slotting in titanium could be doubled with the use of Safe-Lock. The Safe-Lock pull-out tool preventing system is used under license by many tool manufacturers, such as Walter, Sandvik Coromant, Seco Tools, Kennametal and Mapal.