The California and Nevada branch has had an issue at one spot, the turnout at the west end of Mehus Siding, for years.
I just added a 1/4" longer section with clamps at one end to keep it straight.
In the 14 years this branch has been in operation, I have had to add rail to this spot (only place in all 1400’+ of trackage).
This time it was shy 1/4" (joiners still holding).
The alignment hasn’t changed on the tangent approaching, there is a 4 or 5 foot radius 90° curve, and the alignment on the tangent there has not changed.
The curve is still holding the clearance to the buildings outside the curve.
All track is attached to posts or plates.
It has been a real head scratcher.
The new piece of track is 3-3/4" long.
That much in 14 years.
We are all wondering where the rail is disappearing to.