I live in a house that was built in the 1950s. The door frame was made of metal/steel. Since I noticed that the strike plate is missing, I'd like to install a new plate. My question is -- what kind of screws should I be using? Machine screws? If you look at the photo below, the mounting holes look like threaded holes. Thanks in advance.
Yes, metal frames use machine screws, not self-tapping screws.
I’d order a plastic “strike box dust cup” too.
Btw, those existing metal tabs with the screw holes in them are made to be adjusted slightly. I’d be careful moving them, because the screws may not align if you move them too much. However, if the flat head screws do not “seat” properly in the strike plate, you can adjust those tabs.