I was about to declare victory. 622’s chassis was finally rolling reasonably smoothly, or at least more smoothly than #10, and I was giving it a fast run on the rolling road.
Suddenly, the left rear crankpin screw unwound and the connecting rod flew off. The chassis dropped off the rollers, and when I went to put it back together again, I found that the rear driver has lost its quarter!
This is very surprising because it means the epoxy holding the wheelset together failed.
I guess I will call it quits for the night. It’s days like this that make me think that perhaps modelling steam engines is just not for me.

Aargh!
Of all the things to happen, how absolutely hair tearingly, chest thumpingly annoying.
RTR does have some advantages, I must admit but the pride, joy and sheer pleasure of creating your own working model cannot come out of a box!
Best walk away for a while until that creative urge returns in force.
Cheers, John.
Thanks John. Also best to walk away before the urge to throw the whole project against the wall in a fit of rage becomes unbearable!
Oh no! Keep going, though. I’m sure you can get that fixed. Your project is the inspiration for me while I work on getting to a P48 version of my own steam engines.
Thanks JD. I reckon I’ll keep going, but this is definitely one of those low points in the project.
I hope things look better in the morning Rene.
Thanks Mark, I think I have a plan…
Could this in any way be related to your problems with the connecting rod holes?
Craig
It might explain why I was getting some binding. That is, wheels that I thought were solidly quartered were not in fact quartered.