Toolholder System Ensures Highly Accurate Clamping for Complete Pull-Out Protection

Haimer USA has invented Safe-Lock, an EDM form in a shrink fit holder. Prior to the Safe-Lock, the company says, the only way to try and solve the problem of micro creep—when the cutting tool moves slightly and can pull out of the holder—was using a side lock (or Weldon flat) cutting tool and toolholder. However, as the tool was pushed off center, tool life, surface finishes and part accuracies were reduced and assembly remained unbalanced. 

Unlike these friction-based toolholding systems, Haimer notes, when the operator shrinks the holder to insert a cutting tool using Safe-Lock, it engages the Safe-Lock form which includes the grooves on the back end of the cutting tool and a matching EDM form in the holder in the rear of the bore. With about 20 licensed cutting tool manufacturers providing the Safe-Lock grooves on the back of cutting tools as a standard, this feature, combined with Haimer toolholders’ runout accuracy, leads to low vibration and efficient machining.

In addition to the pull out security, Safe-Lock provides very high runout accuracy (<0.003 mm). Haimer claims that only Safe-Lock allows a maximum metal removal rate combined with absolute process reliability and precision. Due to increased cutting depths and feeds, the metal removal rate can be increased by up to 100%, and to a similar degree, tool wear decreases due to optimized runout and balance characteristics.

While Safe-Lock was created in response to the issues heavy-duty machining had to face on a daily basis, it initially made a name for the aerospace and energy industries. However, cost and time savings are not solely restricted to typical aerospace applications and have also been found in typical milling applications. In particular, notes Haimer, the increase in customers utilizing the high-efficiency, dynamic milling strategies available from the CAM software companies, have found Safe-Lock to be a necessity.

With Safe-Lock, machinists experience 100% cutting tool security and highly accurate clamping, due to a form fit clamping combined with an accurate friction fit of shrink fit or high-precision collet chuck technologies. Also, loss of accuracy, tool pull out, spinning of the tool and damages on work piece or machine have been eliminated.