Model size vs print size

[nullsibnelf 2]

Hi

I have the problem that my prints are always smaller than the 3d-model.

I printed a cube with 20mmx20mmx20mm.

Z is correct.

X and Y are 19,7mm.

Is it better correct in Cura (always on every print - with the risk of forgetting it) or to change the step-size in FW?

[Labern 727]

The size can be a factor of many things.

Print temp, speed and material can all effect It plus other factors.

I would create a print profile in CURA and tweak your settings till you get what you require but only use it for that material as it may need adjusting for a different material or even color.

As the part is being printed you get some shrinkage from the plastic as it cools but you also get the filament trying to pull in as its doing each line. This pulling in is what causes it to curl on overhangs. So you may find you can get the outer dimensions correct but the holes can tend to be a lot smaller then what the model is. The hole can be corrected with putting -0.2 horizontal expansion but this will also effect the outer dimensions.

[nullsibnelf 2]

ok. good point. I'll try some more materials and measure the deviation.

Thanks!