Stop UV's Rotating when unwrapped I am trying to unwrap faces which are all exactly the same size. Some have slices through them, but that shouldn't matter should it?   

I am trying to unwrap them to then overlap every single one so that I can make them share the same texture, however when I unwrap them they are all unwrapping at different rotations.     

It's making it a pain to unwrap as it find it impossible and tedious to find out which direction the whole squares are facing.


https://imgur.com/Z1n4M5g
I suggest you use a single seam down the length of the silo (marked in red) and then do a normal UV unwrap. This way the UV layout is connected, and the texture space is used a lot more efficiently.



Generally speaking using overlapping UV is considered bad practice in Substance Painter, because it prevents Painter from baking proper AO maps and the results is generally very unpredictable.