Tuff Stuff 4620 Door Lock Spindle 9/32" Square x 2-5/8" Long 3/8"-20 TPI

Replacement Spindle for Vintage Knobs

The Tuff Stuff 4620 is a new two-piece sectional steel spindle made to replace worn or broken shafts in existing door hardware. It suits homeowners and locksmiths restoring Corbin Russwin, Yale, Marks, Norwalk, National, Baldwin or Tuff Stuff vintage knobs. The 9/32" square profile and 3/8"-20 TPI threading match the original specifications for these brands.

Sectional Design and Thread Constraints

Because the spindle splits into two sections, it fits doors where a solid bar cannot be inserted after the knobs are mounted. The 3/8"-20 thread pitch is fixed; it will not engage hardware cut to a different pitch or diameter. The 2-5/8" overall length sets the maximum door thickness this spindle can bridge without modification.

Upgrade from Damaged Original Shafts

This part replaces a snapped, stripped or corroded original spindle that prevents the latch from retracting. The jump is worth it when the knob rose and lock body are still sound but the connecting shaft has failed. It is not for buyers who need a longer spindle for thicker doors or a different thread standard for non-listed brands.