Another what are these thread....

[Rannsachair]

Amoung a box of clamps I picked up are these, I am only an amateur machinists and wondered what they are for:

this is a bit like a planer setting tool I had, its cast:

then these 2, looks tike the clamp to sheet steel:

 

[Dr.Al]

The top one looks like something you could put onto a plunger style dial gauge to turn it into a lever style dial test indicator.

 

[Sergei Slovenija]

The first two-arm arm is similar to a nozzle for a clock indicator, for example, to make measurements of the inner hole of a part clamped in a lathe chuck (beat value).

 

[Brad93]

The bottom two are a set of key seats.

Hang on to those. Only Starrett make them and I've not found a set yet.

You clamp them to a proper rule, like the ones with combisquares, then you can measure and layout keyways on shafts.

Obviously you could make a set in the mill and harden them, then grind them. tool for life.

 

[Brad93]

The second item is indeed a planer gauge.

First item is a indicator arm to indicate bores using a plunger style dial indicator.