Workholding Tips

Vise locating with Bolt-on Keys versus Sine Keys

Bolt-on keys are a traditional way to locate vises to mills and beds which have t-slots. But today’s machine shops also utilize grid plates with pre-machined hole patterns or mount vises to other style sub-plates and fixture plates for many applications. This usually requires machining mounting holes into the bottom of most vises for these applications.

New Kurt vise models have better and more flexible locating features than previous vise designs. They can still be located to t-slots using sine keys, plus they have additional mounting hole patterns to fit 2″ x 2″, 40mm x 40mm, 50mm x 50mm grid patterns. Kurt vise models using the new Sine Key feature include: DX4 & 6 series, 3400, 3600 & 3800 series, HD690 series, XL6 series, HDL 4 & 6 series and HDM6 series.

Dowel holes for installing sine keys for t-slot mounting or for alternate mounting options

Sine keys

  1. No screws required – o-ring holds securely
  2. Fast mounting: inserts easily into dowel hole
  3. Fast unmounting: sine keys quickly release
  4. Precision mounting to grid plates: 2″ x 2″, 40mm x 40mm, 50mm x 50mm
  5. Alternate mounting made easy. Mount to sub-plates fixture plates and tombstones. No need to drill additional holes in vise base.

Traditional vise keyways for t-slot mounting

Bolt-on keys

  1. Requires mounting with SHCS screws
  2. Slow mounting: uses hex wrench for tightening
  3. Slow unmounting: using hex wrench
  4. No additional mounting features


Click to download an instructional PDF file