Compound replacement

I made a solid relacement block for the Compound of the lathe - It is ground to the same height as the topslide:

The block has two big advantages for me:

  • The Tripan qctp has always the same alignment, which is especially interesting for small production runs, where a collet stop and a stop for the carriage is used.
  • The rigidity of the machine improves noticeable, especially when parting off or using form tools
  • If I need the top slide, it is possible to mount it temporary on the rear of the cross slide and swap the Tripan qctp over:

    The long nut that holds the qctp in place has also a use - It is a nice rigid hardpoint to clamp an indictor to:

    The position of the Tripan qctp is locked in position with a notched plate, that is screwed and pinned in place:

    An argument against such a fixed block instead of the compound is threading, you cant feed along the edge of the thread, like you would with a compound swung around half the included angle of the thread.
    But as I do mainly threads with smaller pitches up to 2mm it is not a huge deal for me - And if I have to do some heavy threading, I can still drop the compound back on.

    An example of a 10x1mm fine thread in 42CrMoS4 steel with straight infeed: