update. may15. correct some sizes, after night print (i check it later)
button thread change to M10x1.5 and size, part3 - center skirt for easy installation
part4 created

part1 full height is 45mm, D40mm (10mm for button guide), threat M40x2 (i print with support, as is, but i think it can be flipped 180 and support don't needed)
part2-1/2-2: D13.6mm, thread is 8x1.25, for rod extension