Multiple-Spindle Thread Verification



Compared to single-spindle designs, the FLX Heads have no performance limits or disadvantages. Each FLX spindle has its own separate torque monitoring; and each spindle provides for separate thread depth setting. The screw threads being gaged don’t need to be all the same size nor the same depth either. As always with the New Vista designs you get (adjustable) limited torque going in, and much greater torque backing out, eliminating the possibility of jamming in the hole.

These “FLX” (multi-spindle) Heads run all the Thread Gage Members in simultaneously, so for applications where short cycles are required they are often the only sensible choice. Once set up and running there is very little maintenance required, and the investment costs have come down a lot in recent years. An FLX Head in 2015 now costs very little more than would a rotary-index (sequential) rig built for the same application.

Sometimes a multiple-spindle thread-verification approach is best. New Vista builds a significant number of Heads and Stations of this configuration every year. The number of spindles generally ranges from 3 to 12 and the Heads are used for round pattern work (bolt circles) and for irregular patterns also.
Here are some videos:

  • A hand-loaded station: This one is in production in India.
  • An automated FLX station on an index table:
  • Torque converters on a conveyorized line: The Torque Converters’ lugs were tapped before being welded in place so the threads are seriously out-of-parallel. Yet the machine never false-rejects, thanks to the New Vista DRGN toolholders that are used here. With conventional (noncompliant) toolholders the station would false-reject at a 10-20% rate!
  • Here’s an ABS (brake system) component that was sequentially tapped on a CNC machine. There are 14 tapped holes here, but the manufacturing engineer in this plant elected to employ a 3-spindle New Vista thread verification station on his palletized line. He is verifying the first hole in the CNC sequence; the last hole; and one in the middle of the sequence.

Solid carbide taper-shank Thread Gage Members are popular in the multi-spindle rigs: in most applications you can run for weeks and often for months without touching anything. For the ultimate in convenience, New Vista Quick-Change Toolholders are often employed: look at It’s hard to see in the video, but each toolholder also has a mechanism for presetting thread depth.

Jack Wickham
New Vista Corporation