One subject that often comes to mind when printing 3D parts, is Dimensional Accuracy.
When printing 3D parts, filament is heated up to be extruded as a thin layer that slowly builds an object. As each layer is placed down, it needs to cool off to become solid again. The process of heating and cooling material in an environment that is affected by external elements (wind, sunlight, air conditioners, heaters, etc) allows for the possibility of the filament slightly expanding or shrinking.
Dimension Accuracy refers to how close to the digital measurement the final print will be. This is slightly different for the two types of materials we offer:
Tolerances for PLA:
When working with PLA, you can expect tolerances of ±0.5% (with a lower limit of ±0.5mm). This means any edge of your object may be at least 0.5mm larger or smaller than in the digital file. This information can be used to ensure parts will fit into each other and means that you should keep in mind that a clearance (tolerance) of about half mm may be needed in both directions.
Tolerances for TPU:
TPU is a more sensitive material and is more severely affected by the process of heating and cooling off, as well as the elements in the environment. This makes tolerances for TPU harder to define. However, TPU is semi-flexible, for which it can slightly stretch and contract.
An important thing to keep in mind when printing in TPU is that, by default, it will be printed with 25% infill. This will make your TPU part 25% solid and may limit flexibility based on your object's geometry. If you require a more flexible part, please let us know in advance. Check this article about custom settings for more information.
And of course, always contact Customer Support if you have any questions!