What is this?

[t4runner]

I picked these up today at a sale really Have no idea what these are for.

 

[scissorman]

Those are inside bore gauges. You would insert one into a cylinder then adjust with a slight drag then you would slide it out and use an outside micrometer to measure.

 

[2oolhound]

http://www.ebay.ca/itm/Vintage-Helios-Machinist-Hole-Gauges-in-Wood-Case-Germany-/251876674387

 

[gearbuilder]

They are small hole gages. Adjust one to a slight drag in a hole you want to know the size of then measure the gage with a micrometer.

Jamie

 

[t4runner]

Thanks for the info.

 

[ToolmakerCT]

To add, those are half ball small hole gages. They can get into shallow bores, they also make full ball ones which I kinda perfer. And Helios is a german manufactuer pretty decent stuff.