Propeller shaft strut set screw

[Navman]

What king of metal is being used as a set screw for the shaft strut ? I am drilling and tapping my strut for one and am undetermined as to what type of metal is best for the bronze strut. I have decided to use a cup type/ concave rather than a point. Of course there is the issue of dissimilar metals causing electrolysis and corrosion.

 

[Afrakes]

Stainless

The original set screws in the 87' strut were stainless steel. They came out easily when I changed the bearing. I replaced them with new stainless set (cup) screws coated with Tef-Gel.