Our old house has storm doors with brass latch bolts and brass strike plates. Brass-on-brass is nicely self-lubricating, unlike the steel-on-steel contraptions available these days, but of late our back door hasn’t been closing smoothly.
I fiddled with the door closer’s tension and release point to no avail, then (re)discovered that a dab of PTFE lubricant on the latch and strike plate makes the storm door close exceedingly smoothly. The base grease is clear and doesn’t make a black mess of things.
Maybe everybody knows that and perhaps I knew it at one time.
I wrote about rebuilding the strike pull and shaft cam of these latches as CNC projects in my Digital Machinist column. Naturally, the replacement latches available in the local hardware stores didn’t fit the door, so the simplest course of action was some quality shop time.