Why does this happen and how do I prevent it?enter image description here

  • Looks like something to do with the snapping to grid or pixel align settings, not sure what exactly but that's where I'd look first – user56reinstatemonica8 Jun 5 '14 at 14:25
  • Ah yes. It was the unholy "Align to Pixel Grid" thing. I didn't expect it though because it's the anchors that should snap and they shouldn't change by changing the line thickness? – noio Jun 6 '14 at 10:47
  • 1
    I think it snaps the edge (or near edge) of the stroke, so the anchors of a 1px line are half way between pixel edges so the line goes from one pixel to another (otherwise a 1px line would be half of one pixel and half of its neighbour), which is why it moves the anchors. Then, it gets stuck because after being scaled up a while the other grid line is closer. – user56reinstatemonica8 Jun 6 '14 at 13:20

Browse other questions tagged or ask your own question.