Are you using pigment/solvent and what sort of media?
If you're not using a RIP my first guess is that the problem is in software. There are too many variables to even possibly take a guess and what could be going wrong. It might be media shrinkage but your figures sound extreme (I'd expect max about 10mm per metre - that would be a lot of media shrinkage).
We notice shrinkage on our media only in the feed direction (print-head direction is 100%). That's easily solved, though - just record what sort of shrinkage you encounter on different medias and then scale up accordingly in the RIP.
Need more info, it could be a multitude of different things, some that could be specific to the brand or model of printer you're using. So, what printer is it? What media? Does this happen with all media that you use or is it just this specific media? Has the machine been calibrated for that specific media? Does the print look OK otherwise, i.e. no banding etc.?
Automatically Autonomous Automation
Although the autonomous car is not quite ready, a lights out print operation is something you can do right now if you have a comprehensive Print MIS (Management Information System). The advantages can put money on your bottom line. So what’s your next step?
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