How can my print be so wrong ? PETG +-5mm diff

[Mathias]

I have designed an enclosure for a PC case I am designing, but I am encountering such a big difference between the print and the 3d model.

Here the dimension is 130mm: as you can see:

And the real print comes up like this: (It is the same model, but as I already had this issue, I cut down the model to print it faster and be sure the mistake was not somewhere else)

Of course, I designed my piece so It tightly fits my components, so nothing works anymore,

Any ideas where this could come from?

[kammmolch]

are all dimensions not accurate or just one? my PETG prints warped / layers ripped apart with the open case. i now have an enclosed printer. otherwise you have to slow the print down like half speed to prevent warping. maybe try that?