Block Plane screw thread

[WVB]

Hi all,
I have a low angle Stanley 60-1/2 block plane with a stripped adjuster thread.
Can anyone advise what the LH thread is in the base where the adjuster screws in ?

I haven't had it long off ebay and although the adjuster screw itself looks ok the thread in the base is what worries me as it seems too large and as though it has been incorrectly tapped out.

I've done some 'thread' searches but cant seem to find much.
Am I right in thinking Stanley used perculiar threads in their planes??

thanks in advance for any tips

[pommyphil]

Stanley appear to make them up as they go along, them change them annually, and once you change country of origin it's a free for all.

Sorry I can't help,