I love tinkercad. one of the things I am doing lately is making custom centering rings for my rockets.
basically a ring to center one tube inside another tube.
only problem is its a bit annoying in tinkercad as there is no way to align the parts. SO if I want to put a 30mm tube inside a 75mm tube I have to divide 75 by 2 and then divide 30 by 2 and subtract the results. this is the "shift"
then I have to lay a ruler and 0 the 75mmt tube to the ruler than drop the 30mm tube and adjust its distance from 0 to be the above calculated shift value.
if I could just say center this part with that part OR center this part with the build platform and then center another part with the build platform. man would that make live easier :-) especially when I have to "tweak" the values and then hve to completely recalculate the shift value.
even if I can't center a part with another part have a BUILD platform center and let me center parts with that.