// hinge plan
hp_rn = hingescrew_nut_dia/2;
-hp_r2 = hp_rn + lever_cover_th;
+hp_r2_min = hp_rn + lever_cover_th;
hp_rs = hingescrew_shaft_dia/2;
-hp_r1 = hp_rs + hingemount_th;
+hp_r1_min = hp_rs + hingemount_th;
+
+hp_r1 = max(hp_r1_min, hp_r2_min);
+hp_r2 = hp_r1;
hppU = lpp13;
hppS = epp2o + [0,-1] * case_th_bottom;