I left it in 32nd stepping, I use the cnc pretty slow, except printing.
@Barry, make sure your drivers weren’t up too high, which can be done in series. It is very noticeably stronger. Sounds like you had a reversed connection. All the pics out there are for a printer z axis, both moving the same way, which would cause your symptoms. We still need to reverse one.
So now, I have tried 16th stepping many times and never noticed a difference. I might just have to by a force gauge and do some better tests. Seriously might have to find smaller steppers if it gets much stronger.