Like carl indicated you need to calibrate your machine most do this by print a 10 mm test cube then you measure it,

Most slicers have a xy compensation and you then can adjust it there.

Just so you know as carl explained this does change in each roll and even on the same roll it can change based on humidity and how much moisture your filament has absorbed.

So if you need accuracy do a calibration before your print.
for most hobbyists you will only need to do it for each roll or maybe only once per type of plastic.
I haven't seen a large variance between rolls of the same brand (that isn't to say I haven't seen any but for what I do its negligible granted I'm totally a hobbyist and doing it for fun so most of my prints don't require high accuracy but when they do I run a calibration test)

You should definitely do it for each type of plastic.

You should also measure the diameter of your filament over  few meters and average it out and include that information in your slicer.

a lot of people don't and that's ok but it does make a difference in the quality of your prints.

Hi guy's
I need a little help i am trying to print a part with holes in it and it seams my printer is not calibrated correctly when i print a part 100x100 MM the printed part is short by 2.5 mm i am using davinci 10 A and repeteir .92 it is now set to 80 mm x 80 mm in the x and y anyone have a setting for these the Z seams ok.

Thanks

It is different per machine. The steps per mm must be dialed in yourself by printing a known size like 50 or 80mm as it usually gets worse on larger parts. Then you add or remove steps depending on need. There is also a setting in most slicers to compensate for this.

In addition there is also something like 3% shrinkage the number mayb wrong but it is noticeble once cooled. This needs to be allowed for in your actual design phase and will be different per each roll installed.

Thanks