I have found that the #58 and #5 couplers work together, and am converting gradually (perhaps too gradually) to the 58s.
Some mention was made of problems on curves because the 58s have a smaller gathering range. May I also mention the potential problem with vertical curves? Particularly, be careful of the change from level track to the start of a grade. The 58s require a more gradual vertical transition from level to grade. Cars equipped with 58s are more likely to uncouple at that transition point, where cars equipped with 5s would not have a problem.
On my old layout in California, I had to go back and ease the transition somewhat at one place, adjusting risers and roadbed. I now use two hi-cube cars (not within the STMFC time period, but helpful) equipped with #58 couplers to test all trackwork. If they stay together, chances are everything else will too.
Tom Wencl <tom.wencl@...>
My standard is Kadee #58's. I also neuter them of their glad hands
since I do not use magnetic uncoupling. An added benefit of neutering
is the effort to uncouple with a skewer is even easier since the
knuckles are free of the resistance of moving the gladhands
along for the ride as well.
I proved this while operating at a friends house and finding it
slightly more difficult to uncouple. I realized it had to be the glad
hands on his equipment requiring more effort while twisting the skewer.
By the way, instead of barbeque skewers, I actually use
an 8 inch length of 3/16" diameter wood dowel with one end sharpened
in a pencil sharpener and deburred with some sandpaper.