reworked carriage.

Begin not an engineer, but developer I couldn't stand the code. Though
I also started to resolve some engineering issues and being developer and
not an engineer, I didn't do that well, but that's a start…

2 files changed, 111 insertions, 144 deletions

diff --git a/X-Axis_carridge2.scad b/X-Axis_carridge2.scad
deleted file mode 100644
index d7285b9..0000000
--- a/X-Axis_carridge2.scad
+++ b/dev/null
@@ -1,144 +0,0 @@
-part="mount"; //mount or carridge
-
-// LM8UU dimentions
-LM8UU_length = 25;
-LM8UU_diameter = 15;
-
-// X Axis dimensions
-x_rod_spacing = 45;
-x_rod_radius = 4;
-
-//Belt
-belt_thickness_no_tooth = 0.75;
-belt_thickness_tooth = 1.45;
-belt_double = belt_thickness_no_tooth+belt_thickness_tooth+0.5;
-
-//Carriage
-carriage_width = 30;
-carriage_padding = 0.1;
-carriage_height = x_rod_spacing+LM8UU_diameter+carriage_padding*2;
-carriage_depth = 12;
-
-//cyclops
-heatbreak_x1=6;
-heatbreak_x2=24;
-heatbreak_z1=3;
-heatbreak_z2=11;
-heatbreak_diameter=4;
-heatsink_baseline=carriage_padding*2+LM8UU_diameter-1;
-mount_x1=15;
-mount_z1=10;
-mount_x2=10.5;
-mount_z2=20;
-mount_x3=19.5;
-mount_z3=20;
-mount_diameter=3.8;
-
-module tie(){
-    difference(){
-        rotate([0,90,0]) cylinder(d=LM8UU_diameter+10, h=4, $fn=50);
-        rotate([0,90,0]) cylinder(d=LM8UU_diameter+3, h=4, $fn=50);
-    }
-}
-
-module heatbreak_hole(){
-    rotate([-90,0,0]) cylinder(d=heatbreak_diameter, h=carriage_depth*2+10, $fn=50);
-    //translate([0,-4,0]) rotate([-90,0,0]) cylinder(d=heatbreak_diameter+3, h=carriage_depth+2, $fn=100);
-}
-
-module mount_hole(){
-    rotate([-90,0,0]) cylinder(d=mount_diameter, h=carriage_depth*2+10, $fn=50);
-    if (part=="carridge") translate([0,-4,0]) rotate([-90,0,0]) cylinder(d=mount_diameter+3, h=carriage_depth+2, $fn=50);
-}
-
-module lug_hole(){
-    rotate([-90,0,0]) cylinder(d=4, h=carriage_depth+2, $fn=50);
-    //translate([0,0,-2]) rotate([-90,0,0]) cylinder(d=5, h=carriage_depth+2, $fn=100);
-}
-
-
-difference(){
-    if (part=="carridge") {
-        //back plane
-        cube(size=[carriage_width,carriage_depth,carriage_height+1]);
-    }
-    else if (part=="mount") {
-        local_height = x_rod_spacing-LM8UU_diameter-carriage_padding*2-3;
-        translate([0,8,LM8UU_diameter+carriage_padding*2]) 
-            cube(size=[carriage_width,8,local_height]);
-    }
-    
-    if (part=="carridge"){
-    //LM8UU
-    translate([2.5,0,carriage_padding+LM8UU_diameter/2]) rotate([0,90,0]) cylinder(d=LM8UU_diameter, h=LM8UU_length, $fn=50);
-    translate([2.5,0,carriage_height-carriage_padding-LM8UU_diameter/2]) rotate([0,90,0]) cylinder(d=LM8UU_diameter, h=LM8UU_length, $fn=50);
-    
-    //ties
-    translate([8,0,carriage_padding+LM8UU_diameter/2]) tie();
-    translate([carriage_width-12,0,carriage_padding+LM8UU_diameter/2]) tie();
-    translate([6,0,carriage_height-carriage_padding-LM8UU_diameter/2]) tie();
-    translate([carriage_width-10,0,carriage_height-carriage_padding-LM8UU_diameter/2]) tie();
-    
-    translate([8,-1,-1]) cube(size=[4,LM8UU_diameter/2,3]);
-    translate([carriage_width-12,-1,-1]) cube(size=[4,LM8UU_diameter/2,3]);
-    
-    //translate([8,LM8UU_diameter/2-.01,LM8UU_diameter/8]) cube(size=[3,carriage_depth,LM8UU_diameter/3*2+1]);
-   // translate([carriage_width-11,LM8UU_diameter/2-.01,LM8UU_diameter/8]) cube(size=[3,carriage_depth,LM8UU_diameter/3*2+1]);
-    
-    //rods
-    translate([-1,0,carriage_padding+x_rod_radius+3.5]) rotate([0,90,0]) cylinder(r=x_rod_radius+2, h=carriage_width+2, $fn=50);
-    translate([-1,0,carriage_height-x_rod_radius-3.5-carriage_padding]) rotate([0,90,0]) cylinder(r=x_rod_radius+2, h=carriage_width+2, $fn=50);
-    
-    //belt
-    translate([-1,-1,LM8UU_diameter+carriage_padding*2+1]) difference(){
-        local_height = x_rod_spacing-LM8UU_diameter-carriage_padding*2-5;
-        cube(size=[carriage_width+2,8,local_height]);
-        
-        //posts
-        translate([3,-1,12.5]) lug_hole();
-        translate([29,-1,12.5]) lug_hole();
-        //channels
-        translate([0,0,carriage_padding*2]){
-            difference() {
-                union() {
-                    translate([1,-1,local_height-belt_double-5]) cube(size=[4,10,5]);
-                    translate([27,-1,local_height-belt_double-5]) cube(size=[4,10,5]);
-                
-                    translate([5,0,local_height-belt_double-2.5]) rotate([-90,0,0]) cylinder(d=5,h=100,$fn=50);
-                    translate([27,0,local_height-belt_double-2.5]) rotate([-90,0,0]) cylinder(d=5,h=100,$fn=50);
-                }
-                translate([5,0,local_height-belt_double-2.5]) rotate([-90,0,0]) cylinder(d=3.5,h=100,$fn=50);
-                translate([27,0,local_height-belt_double-2.5]) rotate([-90,0,0]) cylinder(d=3.5,h=100,$fn=50);
-            }
-        }
-    }
-    }
-   
-    //Cyclops heatbreak 
-    translate([heatbreak_x1,-1,heatbreak_z1+heatsink_baseline]) heatbreak_hole();
-    translate([heatbreak_x2,-1,heatbreak_z1+heatsink_baseline]) heatbreak_hole();
-    translate([heatbreak_x1,-1,heatbreak_z2+heatsink_baseline]) heatbreak_hole();
-    translate([heatbreak_x2,-1,heatbreak_z2+heatsink_baseline]) heatbreak_hole();
-    
-    //Cyclops mount
-    translate([mount_x1,-1,mount_z1+heatsink_baseline]) mount_hole();
-    translate([mount_x2,-1,mount_z2+heatsink_baseline]) mount_hole();
-    translate([mount_x3,-1,mount_z3+heatsink_baseline]) mount_hole();
-     
-    //cooling
-    if (part=="mount") translate([0.001,7,LM8UU_diameter+carriage_padding*2-1]){
-        local_height = x_rod_spacing-LM8UU_diameter-carriage_padding*2+2;
-        translate([2,0,0]) cube(size=[2,3,local_height]);
-        translate([6,0,0]) cube(size=[2,3,local_height]);
-        translate([10,0,0]) cube(size=[2,3,local_height]);
-        translate([14,0,0]) cube(size=[2,3,local_height]);
-        translate([18,0,0]) cube(size=[2,3,local_height]);
-        translate([22,0,0]) cube(size=[2,3,local_height]);
-        translate([26,0,0]) cube(size=[2,3,local_height]);
-    }
-    
-    
-    //translate([-1,LM8UU_diameter/2+1,-1]) cube(size=[carriage_width+2,carriage_depth-LM8UU_diameter/2+1,LM8UU_diameter]);
-}
-
-
diff --git a/x-carriage.scad b/x-carriage.scad
new file mode 100644
index 0000000..a546bb7
--- a/dev/null
+++ b/x-carriage.scad
@@ -0,0 +1,111 @@
+slide_tolerance = .3;
+play_tolerance=.4;
+fit_tolerance = .2;
+
+bearings_l = 25;	// 15;
+bearings_d = 15;	// 12;
+bearings_m = 2.5;	// thickness of the bearing end holder
+bearings_s = 4.5;	// the minimum shell between bearings and carriage front
+
+rods_apart = 45;
+rod_d = 8;
+
+mounting_holes_from_top = [	// the offsets of mounting holes on the back
+ [0, 20], [-4.5,10], [4.5,10]
+];
+mounting_holes_apart = mounting_holes_from_top[2][0]-mounting_holes_from_top[1][0];
+
+belt_tooth=0.70;
+belt_thickness=0.75;
+belts_thickness = belt_thickness*2+belt_tooth+0.5;
+belt_width = 6;
+belts_apart = 12;
+belt_pitch = 2;
+
+tiehole_id = bearings_d+3;
+tiehole_od = bearings_d+10;
+tiehole_w = 4;
+
+screw_d = 3;
+screwhead_d = 5.5;
+screwhead_h = 3;
+
+module belt(pitch=belt_pitch,width=belt_width,thickness=belt_thickness,tooth=belt_tooth,l=100,tolerance=0) {
+ translate([-l/2,-width/2,-thickness])
+ intersection() {
+  union() {
+   cube(size=[l,width,thickness+tolerance]);
+   for(x=[0:pitch:l/2]) for(s=[-1,1])
+    translate([l/2+s*x,0,thickness])
+    rotate([-90,0,0])
+    cylinder(r=tooth+tolerance,h=width,$fn=6);
+  }
+  translate([0,-1,0])
+  cube(size=[l,width+2,thickness+tooth+1]);
+ }
+}
+
+module xcarriage() {
+ cw = bearings_l+2*bearings_m;	// carriage width
+ % for(mz=[0,1]) mirror([0,0,mz]) translate([0,0,-belts_apart/2]) belt();
+ difference() {
+  translate([-cw/2,-belt_width/2,-rods_apart/2-bearings_d/2])
+  cube(size=[cw,bearings_d/2+bearings_s+belt_width/2,rods_apart+bearings_d]);
+
+  for(sz=[-1,1]) translate([0,0,sz*rods_apart/2]) {
+   rotate([0,90,0])
+   cylinder(d=bearings_d,bearings_l,center=true,$fn=60);
+   for(sx=[-1,1]) translate([sx*bearings_l/4,0,0])
+    rotate([0,90,0]) difference() {
+     cylinder(d=tiehole_od,h=tiehole_w,center=true,$fn=60);
+     cylinder(d=tiehole_id,h=tiehole_w+2,center=true,$fn=60);
+    }
+   rotate([0,90,0]) cylinder(d=bearings_d-bearings_m,h=cw+2,center=true,$fn=60);
+  }
+
+  difference() {
+   gap=3;
+   translate([0,-.5,-gap/2])
+   cube(size=[cw+2,belt_width+2,belts_apart+2*belt_thickness+gap],center=true);
+   for(mx=[0,1]) mirror([mx,0,0]) {
+    ofc = mounting_holes_apart/2+screwhead_d/2+belt_thickness+belt_tooth+play_tolerance; // offset from center
+    r=1;
+    x0 = ofc+r; x1=cw/2-r;
+    z0 = r; z1 = belts_apart/2-belt_thickness;
+    difference() {
+     hull() for(x=[x0,x1]) for(z=[z0,z1])
+      translate([x,0,z])
+      rotate([90,0,0]) cylinder(r=r,h=belt_width+2,center=true,$fn=30);
+     translate([cw/2,0,belts_apart/2]) mirror([0,0,1]) belt(width=belt_width+2,l=cw/2+2,tolerance=fit_tolerance);
+    }
+    bgap = belt_thickness+belt_tooth+fit_tolerance;
+    r1 = (belts_apart/3-bgap)/2;
+    echo(r1);
+    hull() for(x=[mounting_holes_apart/2,x1])
+     translate([x,0,-r1-bgap])
+     rotate([90,0,0]) cylinder(r=r1,h=belt_width+2,center=true,$fn=30);
+    dgn= sqrt(pow(x1-x0,2)+pow(z1-z0,2));
+    echo(dgn);
+    translate([x0,0,z0])
+    rotate([90,0,0])
+    * cylinder(r=dgn/2-r-belt_thickness,h=belt_width+2,center=true,$fn=30);
+    /*
+    pd = 4.5;	// post diameter
+    bhd = 5;	// belt holder diameter
+    translate([cw/2-pd/2,0,belts_apart/2-belts_thickness-bhd/2]) cube(size=[pd,belt_width,bhd],center=true);
+    translate([(cw-pd)/2,0,0]) // TODO: z
+    rotate([-90,0,0]) translate([0,0,-1]) cylinder(d=pd,h=belt_width+2,center=true,$fn=30); */
+   }
+  } // difference
+
+  translate([0,0,30/*heatsink height*//2])
+  for(mhft = mounting_holes_from_top) translate([mhft[0],0,-mhft[1]]) {
+   rotate([90,0,0]) cylinder(d=screw_d+2*play_tolerance,h=bearings_d+2*bearings_s+2,center=true,$fn=30);
+   translate([0,belt_width/2+screwhead_h+play_tolerance,0])
+   rotate([90,0,0]) cylinder(d=screwhead_d+2*play_tolerance,h=screwhead_h+play_tolerance+1,$fn=30);
+  }
+ } // difference
+}
+
+xcarriage();
+