I'm pretty sure I found the problem!
I decided to examine the bot a lot more closely after re-re-re-measuring the tower heights and found this:
That looks a bit warped, huh?
Took it apart and this is the platform:
So, I'm going to print another one in ABS at a fairly high infill density and try that.
I did a couple of test prints without the fan, so maybe that caused it? In either case, this is pretty surely the source of my weirdness.
I decided to examine the bot a lot more closely after re-re-re-measuring the tower heights and found this:
That looks a bit warped, huh?
Took it apart and this is the platform:
So, I'm going to print another one in ABS at a fairly high infill density and try that.
I did a couple of test prints without the fan, so maybe that caused it? In either case, this is pretty surely the source of my weirdness.