@f_verbaas yes, that is, essentially, parameterising the helicoid (zero thickness path) of the spring as [ c.t, R.sin(t), R.cos(t) ], where R is the spring radius. The spring thickness (r) is applied to the helicoid as a surface normal displacement after the scaling (c) is calculated. Displacement won't be affected by scaling provided the morph is applied after the transforms (afterBend flag set). I think for existing spring props, I will have to analyse and provide some inputs, like R (helicoid radius = (OutsideDiameter + InsideDiameter)/4), r (spring wire radius = (OutsideDiameter - InsideDiameter)/2), chirality (CW or ACW spiral) and number of turns. A python script should be possible to derive an axial scaling morph. @karina there's soooo much conflicting information about historical weapons, that I thought I should share this link . I don't expect it to change anyone's opinions, especially when there's family history involved. I get most of my weapons intel via Quora, where much care must be taken to winnow opinion from fact.