Trying to identify

[Flight Mech.]

IMG_0144.jpg

IMG_0145.jpg

IMG_0146.jpgTrying to identify prop. Looks like a Hartzell from other pictures in this forum.
100 inches long. Bore = 2 3/4 inch, eight 3/8 inch bolt holes, 4 3/8 in. thick at the bore. Flange diameter = 7 1/2 " Numbers visible= SC4100, Copper metal on tips and part way up leading edge. Small diagram visible which looks like a 4 leaf clover with the letters U, S, A, one in each clover leaf.

[MWP_Lamar]

Can you post pictures here? I'm going to guess that the SC4100 is a US Signal Corps designation.

Lamar

[Flight Mech.]

Flight mech

Pictures are posted also a couple of other items noted.

[Dave]

I'm guessing that it was designed either for an OX5 engine or a Hall Scott A2A engine. They are very similar, but the bolt diameter circle for the Hall Scott is 6" instead of 5 1/4" for the JN4. See this page for details.

The geometric shape is very similar to this Standard J1 prop, but it's a few inches shorter than yours is. (But here is another J1 prop that is 100" diameter.)