Here is an example of a pivot repair on a 1940s Gruen Veri-Thin. As seen in the picture, the upper pivot of the center wheel has deep groves worn for years of running, perhaps without lubricant.
This is tricky repair as this calibre has a center sweep second hand, and the center post is hollow. Re-pivoting involves turning the center pivot down on a lathe just enough to slip a steel sleeve over the original pivot. Care is taken not to make the existing post walls too thin.
The newly made sleeve is gently pressed, and this Gruen has a new lease on life.