Hi Chuck.
Been there. For metal I like to use JB Weld epoxy. Holds threads nicely and super strong. There are a multitude of ways to fix holes. Once at a train show on a tender draw bar I put a shaving from a toothpick in the hole and drove the screw home. Still in there more than a decade later.
I haven't tried it but some guys swear by mixing super glue in flour. Keeps the shrinkage down and fills the hole.
Glad you fixed it.
Pete.
OK, it wasn't a disaster in the sense of an earthquake or a flood but the car is an Ulrich all-metal box car that I've had for at least 50 years.
The problem was actually stripped threads inside the insulation plug in the metal floor of the car. The king pin screw would simply not hold and I didn't have a slightly larger screw to fix the problem.
Solution: I filled the kingpin hole with Gorilla Super Glue (any good AC would probably work as well but I've had excellent results with Gorilla). The glue was allowed to set overnight. It actually shrunk while setting so I repeated the glue treatment twice before I was satisfied that the hole was filled.
A #50 drill and a 2-56 tap finished the job and the car is ready to return to service! (I wasn't going to tap the hole but the Gorilla glue was too tough for a simple self-tapping screw.
ChuckAllen, TX