topeak-mtx-tortec-expeditionrack-adapter: wip

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/topeak-mtx-tortec-expeditionrack-adapter.scad b/topeak-mtx-tortec-expeditionrack-adapter.scad
index 2cdfd6f88ed833c05ccf35438e5b37a01f5506ee..e7cc0375a42d1216b673f506e0583459aa8d4285 100644 (file)
--- a/topeak-mtx-tortec-expeditionrack-adapter.scad
+++ b/topeak-mtx-tortec-expeditionrack-adapter.scad
@@ -75,7 +75,7 @@ block_y_min = adapt_main_top_y - main_sz_y;
 
 strap_barrel_x = rack_width_inner/2 + strap_barrel_dia/2;
 
-rack_shear_ratio = rear_elevation_nominal / rear_to_front_distance;
+rack_shear_ratio = -rear_elevation_nominal / rear_to_front_distance;
 
 brk_bolt_nut_top_y = -brk_nearbolt_recess_depth
   - brk_bolt_eff_len + brk_bolt_nut_th + brk_bolt_len_slop;
@@ -250,9 +250,10 @@ module Principal(){
              rectfromto([ -$foreaftmaint_rail_z, adapt_main_top_y ],
                         [ 0, block_y_min]);
              hull(){
+               ybot = $foreaftmaint_rail_y - rack_rail_dia/2 + grasp_large_r
+                 - fit_slope_len * 0.5;
                for (y = [
-                         $foreaftmaint_rail_y
-                         - rack_rail_dia/2 + grasp_large_r,
+                         ybot,
                          adapt_main_top_y - grasp_large_r
                          ])
                  for (dx= [-1,+1] * rack_rail_dia/2)
@@ -283,13 +284,23 @@ module Principal(){
 
     // Distance from bolt hole, in backwards direction
     AsForeAftMaint(){
+      cr = rack_rail_dia/2 + foreaftmaint_r_slop;
       translate([ 0, $foreaftmaint_rail_y, $foreaftmaint_rail_z ])
        linextr_x_yz(+rack_rail_x,
                     -rack_rail_x) {
        hull(){
          for (dy=[0,50]) {
            translate([-dy,0])
-             circle(r= rack_rail_dia/2 + foreaftmaint_r_slop);
+             circle(r= cr);
+         }
+       }
+       hull(){
+         for (dd=[[0,0], [-1,-1], [-1,+1]]) {
+           translate(
+                     [-1, 0] * (rack_rail_dia - fit_slope_len)
+                     + 20 * dd
+                     )
+             circle(r= cr);
          }
        }
       }