feat: support crosshair base for single magnet

gridfinity-rebuilt-baseplate.scad

@@ -48,12 +48,15 @@ fity = 0; // [-1:0.1:1]
 /* [Styles] */
 
 // baseplate styles
-style_plate = 0; // [0: thin, 1:weighted, 2:skeletonized, 3: screw together, 4: screw together minimal]
+style_plate = 0; // [0: thin, 1:weighted, 2:skeletonized, 3: screw together, 4: screw together minimal, 5:crosshair, 6:screw together crosshair]
 
 
 // hole styles
 style_hole = 2; // [0:none, 1:countersink, 2:counterbore]
 
+// spoke width of crosshair
+spoke_width = 3; // [2:1:24]
+
 /* [Magnet Hole] */
 // Baseplate will have holes for 6mm Diameter x 2mm high magnets.
 enable_magnet = true;
@@ -64,12 +67,12 @@ chamfer_holes = true;
 
 hole_options = bundle_hole_options(refined_hole=false, magnet_hole=enable_magnet, screw_hole=false, crush_ribs=crush_ribs, chamfer=chamfer_holes, supportless=false);
 
+
 // ===== IMPLEMENTATION ===== //
 
 color("tomato")
 gridfinityBaseplate(gridx, gridy, l_grid, distancex, distancey, style_plate, hole_options, style_hole, fitx, fity);
 
-
 // ===== CONSTRUCTION ===== //
 
 module gridfinityBaseplate(gridx, gridy, length, dix, diy, sp, hole_options, sh, fitx, fity) {
@@ -109,9 +112,12 @@ module gridfinityBaseplate(gridx, gridy, length, dix, diy, sp, hole_options, sh,
                 else if (sp == 4)
                     translate([0,0,-5*(h_base+off)])
                     rounded_square(length-2*r_c2-2*r_c1, 10*(h_base+off), r_fo3);
+                else if (sp == 5 || sp == 6)
+                    linear_extrude(10*(h_base+off), center = true)
+                    profile_crosshair();
 
-
-                hole_pattern(){
+                single_hole=sp==5||sp==6;
+                hole_pattern(l=l_grid, single_hole){
                     mirror([0, 0, 1])
                     block_base_hole(hole_options);
 
@@ -121,15 +127,14 @@ module gridfinityBaseplate(gridx, gridy, length, dix, diy, sp, hole_options, sh,
                 }
             }
         }
-        screw_together = sp == 3 || sp == 4;
+        screw_together = sp == 3 || sp == 4 || sp == 6;
         if (screw_together) cutter_screw_together(gx, gy, off);
     }
-
 }
 
 function calculate_offset(style_plate, enable_magnet, style_hole) =
-    assert(style_plate >=0 && style_plate <=4)
-    let (screw_together = style_plate == 3 || style_plate == 4)
+    assert(style_plate >= 0 && style_plate <= 6)
+    let (screw_together = style_plate == 3 || style_plate == 4 || style_plate == 6)
     screw_together ? 6.75 :
     style_plate==0 ? 0 :
     style_plate==1 ? bp_h_bot :
@@ -157,13 +162,6 @@ module cutter_weight() {
         }
     }
 }
-module hole_pattern(){
-    pattern_circular(4)
-    translate([l_grid/2-d_hole_from_side, l_grid/2-d_hole_from_side, 0]) {
-        render();
-        children();
-    }
-}
 
 module cutter_countersink(){
     screw_hole(SCREW_HOLE_RADIUS + d_clear, 2*h_base,
@@ -192,12 +190,33 @@ module profile_skeleton() {
             minkowski() {
                 square([l,l]);
                 circle(MAGNET_HOLE_RADIUS+r_skel+2);
-           }
+            }
         }
         circle(r_skel);
     }
 }
 
+module profile_crosshair() {
+    l_grid_inner = l_grid - 2*r_c2 - 2*r_c1; // l without chamfers
+    l_grid_inner_minkowski = l_grid_inner / 2 - r_f1;
+
+     // sqrt 2 because of 45 degree angle
+    spoke_offset=sqrt(2)*spoke_width/2;
+
+    pattern_circular(4)
+    difference() {
+      minkowski() {
+        polygon([
+          [spoke_offset, 0],
+          [l_grid_inner_minkowski, l_grid_inner_minkowski - spoke_offset],
+          [l_grid_inner_minkowski, -l_grid_inner_minkowski + spoke_offset],
+         ]);
+         circle(r_f1);
+      }
+      circle(MAGNET_HOLE_RADIUS+r_skel);
+    }
+}
+
 module cutter_screw_together(gx, gy, off) {
 
     screw(gx, gy);

gridfinity-rebuilt-bins.scad

@@ -78,6 +78,8 @@ scoop = 1; //[0:0.1:1]
 div_base_x = 0;
 // number of divisions per 1 unit of base along the Y axis. (default 1, only use integers. 0 means automatically guess the right division)
 div_base_y = 0;
+// Base will have a single hole in the center (use with crosshair style base)
+single_hole = false;
 
 /* [Base Hole Options] */
 // only cut magnet/screw holes at the corners of the bin to save uneccesary print time
@@ -111,7 +113,7 @@ gridfinityInit(gridx, gridy, height(gridz, gridz_define, style_lip, enable_zsnap
         cutCylinders(n_divx=cdivx, n_divy=cdivy, cylinder_diameter=cd, cylinder_height=ch, coutout_depth=c_depth, orientation=c_orientation, chamfer=c_chamfer);
     }
 }
-gridfinityBase(gridx, gridy, l_grid, div_base_x, div_base_y, hole_options, only_corners=only_corners);
+gridfinityBase(gridx, gridy, l_grid, div_base_x, div_base_y, hole_options, only_corners=only_corners, single_hole=single_hole);
 }
 
 

gridfinity-rebuilt-utility.scad

@@ -210,7 +210,7 @@ module profile_base() {
     ]);
 }
 
-module gridfinityBase(gx, gy, l, dx, dy, hole_options=bundle_hole_options(), off=0, final_cut=true, only_corners=false) {
+module gridfinityBase(gx, gy, l, dx, dy, hole_options=bundle_hole_options(), off=0, final_cut=true, only_corners=false, single_hole=false) {
     dbnxt = [for (i=[1:5]) if (abs(gx*i)%1 < 0.001 || abs(gx*i)%1 > 0.999) i];
     dbnyt = [for (i=[1:5]) if (abs(gy*i)%1 < 0.001 || abs(gy*i)%1 > 0.999) i];
     dbnx = 1/(dx==0 ? len(dbnxt) > 0 ? dbnxt[0] : 1 : round(dx));
@@ -218,25 +218,27 @@ module gridfinityBase(gx, gy, l, dx, dy, hole_options=bundle_hole_options(), off
     xx = gx*l-0.5;
     yy = gy*l-0.5;
 
-    if (final_cut)
-    translate([0,0,h_base])
-    rounded_rectangle(xx+0.002, yy+0.002, h_bot/1.5, r_fo1+0.001);
+    if (final_cut) {
+        translate([0,0,h_base])
+        rounded_rectangle(xx+0.002, yy+0.002, h_bot/1.5, r_fo1+0.001);
+    }
 
     intersection(){
-        if (final_cut)
-        translate([0,0,-1])
-        rounded_rectangle(xx+0.005, yy+0.005, h_base+h_bot/2*10, r_fo1+0.001);
+        if (final_cut) {
+            translate([0,0,-1])
+            rounded_rectangle(xx+0.005, yy+0.005, h_base+h_bot/2*10, r_fo1+0.001);
+        }
 
         if(only_corners) {
             difference(){
                 pattern_linear(gx/dbnx, gy/dbny, dbnx*l, dbny*l)
-                block_base(gx, gy, l, dbnx, dbny, 0, off);
+                block_base(gx, gy, l, dbnx, dbny, [], off);
 
                 copy_mirror([0, 1, 0]) {
                     copy_mirror([1, 0, 0]) {
                         translate([
-                            (gx/2)*l_grid - d_hole_from_side,
-                            (gy/2) * l_grid - d_hole_from_side,
+                            (gx/2)*l_grid - (single_hole ? l_grid/2 : d_hole_from_side),
+                            (gy/2)*l_grid - (single_hole ? l_grid/2 : d_hole_from_side),
                             0
                         ])
                         block_base_hole(hole_options, off);
@@ -246,13 +248,29 @@ module gridfinityBase(gx, gy, l, dx, dy, hole_options=bundle_hole_options(), off
         }
         else {
             pattern_linear(gx/dbnx, gy/dbny, dbnx*l, dbny*l)
-            block_base(gx, gy, l, dbnx, dbny, hole_options, off);
+            block_base(gx, gy, l, dbnx, dbny, hole_options, off, single_hole=single_hole);
         }
     }
 }
 
 /**
- * @brief A single Gridfinity base.  With holes (if set).
+ * @brief Apply hole pattern to children
+ * @param l
+ * @param single_hole Use a single hole, default = false
+ */
+module hole_pattern(l, single_hole=false){
+    hole_offset = single_hole ? 0 : l/2 - d_hole_from_side;
+    steps= (single_hole || abs(l - d_hole_from_side/2) < 0.001) ? 1 : 4;
+
+    pattern_circular(steps)
+    translate([hole_offset, hole_offset, 0]) {
+        render();
+        children();
+    }
+}
+
+/**
+ * @brief A single Gridfinity base. With holes (if set).
  * @param gx
  * @param gy
  * @param l
@@ -261,14 +279,14 @@ module gridfinityBase(gx, gy, l, dx, dy, hole_options=bundle_hole_options(), off
  * @param hole_options @see block_base_hole.hole_options
  * @param off
  */
-module block_base(gx, gy, l, dbnx, dbny, hole_options, off) {
+module block_base(gx, gy, l, dbnx, dbny, hole_options, off, single_hole=false) {
     render(convexity = 2)
     difference() {
         block_base_solid(dbnx, dbny, l, off);
-
-        pattern_circular(abs(l-d_hole_from_side/2)<0.001?1:4)
-        translate([l/2-d_hole_from_side, l/2-d_hole_from_side, 0])
-        block_base_hole(hole_options, off);
+  
+        hole_pattern(l, single_hole=single_hole) {
+          block_base_hole(hole_options, off);
+        }
     }
 }
 

tests/test_baseplate.py

@@ -111,6 +111,16 @@ class TestBasePlateHoles(unittest.TestCase):
         self.scad_runner.camera_arguments = self.scad_runner.camera_arguments.with_rotation(CameraRotations.AngledTop)
         self.scad_runner.create_image([], Path('magnet_and_counterbored_screw_holes_top.png'))
 
+    def test_crosshair_with_magnet(self):
+        vars = self.scad_runner.parameters
+        vars["enable_magnet"] = True
+        vars["chamfer_holes"] = False
+        vars["crush_ribs"] = False
+        vars["style_plate"] = 5
+        self.scad_runner.create_image([], Path('crosshair_with_magnet_bottom.png'))
+        self.scad_runner.camera_arguments = self.scad_runner.camera_arguments.with_rotation(CameraRotations.AngledTop)
+        self.scad_runner.create_image([], Path('crosshair_with_magnet_top.png'))
+
 
 if __name__ == '__main__':
     unittest.main()