Method for determining a manufacturing parameter for making an aligner with a desired aligner thickness using a thermoforming device operable for making the aligner by shaping a precursor aligner into the aligner using a mold representative of a dental archform, the method comprising: obtaining a 3D map associated with the dental archform; parsing the 3D map to determine a first property value and a second property value, the first property value being based on the 3D map and the second property value being derived from a 2D projection of the 3D map, and determining a thickness of the precursor aligner for obtaining the desired aligner thickness based on a ratio of the first property value and the second property value and a given value of an operating parameter of the thermoforming device; and sending instructions to the thermoforming device to make the desired aligner based on the determined operating parameter.