For scaling there are 3 options.
- Scale factor: this allows you to scale all directions or a single direction by a factor.
- To fixed size: this allows scaling to a fixed size. Uncheck the box at the bottom to leave the other dimensions unchanged. Otherwise they will scale with the same factor.
- To build table: use this option to scale to a maximum number of objects. The algorithm checks the boundingbox of your object minus a padding and scales towards the number of desired copies.
Your supports or any other attached objects to the part are scaled as well.
Mirroring allows you to create a mirror of the part in a chosen axis. This can be handy if you are printing mechanical parts that need a mirrored duplicate. You only have to support your part once in this case, saving you work.