What is this?

[George of the Wood]

A friend was cleaning out her deceased father's workshop and brought me this layout devise that has me stumped. After lurking here for years, I know that someone would know just what we have here. The main part(s) appear to me to be a sector---but the second scale (on each leg's left side) appears to be all out of proportion. Also, the middle leg in the pictures is fitted with what appears to be a mechanical pencil type lead holder. Further, there is a eyelet screw on one of the main legs that may or may not belong. There is no maker's mark on the thing, but the numbers are printed too uniformly to be hand drawn.

Conjecture on my part is that perhaps it is a sector that can somehow be adapted to draw ellipses. If so, how? Anyone have an idea what this devise is and how to use it?

 

[pat from Marck]

Did you ever find out what this is or did

 

[paulrbarnard]

A friend was cleaning out her deceased father's workshop and brought me this layout devise that has me stumped. After lurking here for years, I know that someone would know just what we have here. The main part(s) appear to me to be a sector---but the second scale (on each leg's left side) appears to be all out of proportion. Also, the middle leg in the pictures is fitted with what appears to be a mechanical pencil type lead holder. Further, there is a eyelet screw on one of the main legs that may or may not belong. There is no maker's mark on the thing, but the numbers are printed too uniformly to be hand drawn.

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Conjecture on my part is that perhaps it is a sector that can somehow be adapted to draw ellipses. If so, how? Anyone have an idea what this devise is and how to use it?

A pantograph scaler but missing a leg.

 

[pat from Marck]

A pantograph scaler but missing a leg.

Nifty bit of kit learn something new every day ta

 

[George of the Wood]

Well now. Mystery appears to be solved! Thank you Paul.