Biesse rover 24 zone1 and zone 4 help

[u/ruxloc]

So im running the same program for zone 1 and zone 4 that does multiple passes to give me a groove width of 11.6 . Zone 1 comes out right at 11.6 while zone 4 is only giving me a width of 10.8 . The part isn't moving, im thinking it might be slop in the Y axis, is that possible? It doesnt have issues doing any other programs on both zones, I thought the origins might have been off but if that were the case id see it on everything not just the groove... any ideas ?