I am looking at the possibility of repairing an adjuster belonging to a Norris A1 plane. The shaft has sheared off inside the swivel. To do the repair it looks a new threaded end would need to be grafted onto the shaft (as well as extracting the broken bit from the swivel). This will only be possible if the correct tap and die can be found. Does anyone know what sizes of threads Norris used? I have not yet examined the adjuster but from the photos sent to me I estimate that the larger thread is 1/4" x 40 TPI RH (which is no problem). The smaller thread is LH and might be about 50 TPI or 0.5 mm pitch.
76.3 KB Views: 623
116.2 KB Views: 623