3 screwrad = 4.3 / 2 + 0.30;
4 shaftrad = 7.5 / 2 - 0.30;
6 diskrad = 12.0 / 2 - 0.25;
10 csinkdepth = 3.4 * csinkpart;
11 screwheadrad = (8.1 * csinkpart + screwrad * (1-csinkpart)) / 2 + 0.30;
21 disktaperrad = diskrad - diskthick / disktaperratio;
22 totallen = shaftlen + diskthick;
24 echo(disktaperrad, screwheadrad);
25 echo(diskrad, disktaperrad, shaftrad, screwheadrad, screwrad);
28 polygon([[-screwheadrad, 0],
30 [-diskrad, -diskthick],
31 [-shaftrad, -diskthick],
32 [-shaftrad, -totallen],
33 [-screwrad, -totallen],
34 [-screwrad, -csinkdepth]]);