time ago I started to have registration problems between some screens. I finished to think I stretched too much the roller frames and the mesh simply needed to set. Then I tried to register the films between them and I've discovered they don't line up.

I haven't changed my printer or film. On a 4 colours job 3 of them line up perfectly. On another 3 color job 2 of them line up perfectly.

Is possible the film affects of sizing? Or some part of the roll aren't perfectly even?

Should I consider also the sliding mechanism into the printer?

Thanks you all,