Revise platform bolt patterns and alignments

Updated the platform deck, angle iron, and pivot bracket modules to use new bolt patterns and offsets for improved alignment and assembly. Added a third bolt to transverse angles, moved side angle and bracket bolts to new positions with defined offsets, and synchronized hole locations across deck, angle iron, and bracket parts. Introduced new parameters for side gap and bolt offsets in lifetrac_v25_params.scad to ensure consistent spacing and collision avoidance.

Author: dorkmo

LifeTrac-v25/mechanical_design/openscad/lifetrac_v25.scad

@@ -2414,8 +2414,8 @@ module platform_transverse_angle(length) {
         }
 
         // Deck Mounting Holes (Vertical through Horizontal Leg)
-        // 2 bolts: Near ends (aligned with side rails)
-        for (x_pos = [-length/2 + PLATFORM_TRANSVERSE_BOLT_END_OFFSET, length/2 - PLATFORM_TRANSVERSE_BOLT_END_OFFSET]) {
+        // 3 bolts: Near ends and Center
+        for (x_pos = [-length/2 + PLATFORM_TRANSVERSE_BOLT_END_OFFSET, 0, length/2 - PLATFORM_TRANSVERSE_BOLT_END_OFFSET]) {
             translate([x_pos, leg/2, 0])
             cylinder(d=angle_bolt_hole_dia, h=thick*3, center=true, $fn=24);
         }
@@ -2443,19 +2443,109 @@ module platform_angle_iron(length=0, is_side=false) {
             // Pivot Holes (Start) - Horizontal Holes through Vertical Leg (Leg 1)
             // Leg 1 is along X. Normal Y. Holes along Y.
             // 2 holes for bolts into the L shaped pivot plate
-            // Positions: PLATFORM_SIDE_BOLT_START and + SPACING
-            for (z_pos = [PLATFORM_SIDE_BOLT_START, PLATFORM_SIDE_BOLT_START + PLATFORM_SIDE_BOLT_SPACING]) {
-                translate([PLATFORM_ANGLE_LEG/2, PLATFORM_ANGLE_THICK/2, z_pos])
-                rotate([90, 0, 0]) // Align with Y axis
+            
+            // Replicate calculations to align with platform_pivot_bracket
+            
+            // 1. Calculate side_angle_start_y (World Y of Angle Iron Start)
+            // From assembly:
+            deck_pivot_y = PLATFORM_BRACKET_WIDTH/2;
+            front_angle_corner_y = deck_pivot_y - PLATFORM_EDGE_MARGIN - PLATFORM_ANGLE_LEG;
+            gap = 12.7;
+            side_angle_start_y = front_angle_corner_y - gap;
+            
+            // 2. Calculate bolt positions
+            // Bracket bolts are on Leg 2 (File X -> Assembly -Y).
+            // Bracket Y is constant `bolt_y`.
+            // Bracket X varies: bolt_x_1, bolt_x_2.
+            
+            corner_y = -PLATFORM_LOCK_OFFSET + PLATFORM_SIDE_BOLT_Y_OFFSET;
+            bracket_width = PLATFORM_BRACKET_WIDTH;
+            leg2_length = PLATFORM_BRACKET_LENGTH - bracket_width/2;
+            bx_1 = pivot_bolt_offset;
+            bx_2 = leg2_length - pivot_bolt_offset;
+            
+            // 3. Map to Angle Iron Coordinates
+            // Angle Iron Local Z (Longitudinal) corresponds to Assembly -Y.
+            // Angle Iron Local X (Leg 1) corresponds to Assembly Z.
+            
+            // Longitudinal Position (z_pos)
+            // Matches Bracket X (bx).
+            // z_pos = bx.
+            // Wait. Bracket X is distance from Pivot (along Leg 2).
+            // Angle Iron Z is distance from Angle Start.
+            // Angle Start is at side_angle_start_y.
+            // Pivot is at 0 (in Y).
+            // But Angle Iron is translated by side_angle_z_trans.
+            // side_angle_z_trans = PLATFORM_LOCK_OFFSET - side_angle_start_y.
+            // This is confusing.
+            // Let's use the fact that Bracket X=0 is at Corner.
+            // Corner is at Y = corner_y (in Bracket Local Y).
+            // But Bracket Leg 2 starts at X=0.
+            // In Assembly, Bracket Leg 2 starts at Pivot Y? No.
+            // Bracket Leg 2 starts at Corner Y?
+            // Bracket Leg 2 is the Horizontal Leg.
+            // It extends from Corner (Y=-130) backwards?
+            // No, Bracket Leg 2 is along Local X.
+            // Local X maps to World -Y.
+            // So it extends from Y=0 (Pivot) to Y=-Length?
+            // No, Bracket Local X=0 is at Pivot Y?
+            // In `platform_pivot_bracket`, X=0 is at Pivot X.
+            // So Bracket Leg 2 starts at Pivot X (which is 0).
+            // So Bracket X is distance from Pivot.
+            // So bx is distance from Pivot.
+            
+            // Angle Iron Start is at side_angle_start_y (World Y).
+            // Angle Iron extends along -Y.
+            // So Angle Iron Z=0 is at side_angle_start_y.
+            // Angle Iron Z=z_pos is at Y = side_angle_start_y - z_pos.
+            // We want Y = -bx (since Bracket X maps to -Y).
+            // side_angle_start_y - z_pos = -bx.
+            // z_pos = side_angle_start_y + bx.
+            
+            z_pos_1 = side_angle_start_y + bx_1;
+            z_pos_2 = side_angle_start_y + bx_2;
+            
+            // Vertical Position (x_pos on profile)
+            // Matches Bracket Y (bolt_y).
+            // Bracket Y maps to World Z.
+            // Angle Iron X maps to World Z? No.
+            // Angle Iron Local X (Leg 1) -> Frame -Y -> World -Z.
+            // Angle Iron Local Y (Leg 2) -> Frame X -> World X.
+            // Angle Iron Local Z -> Frame Z -> World -Y.
+            
+            // Wait. If Angle Iron Local X -> World -Z.
+            // Then Angle Iron X is Vertical (Down).
+            // Bracket Y is Vertical (Up/Down).
+            // Bracket Y = corner_y - width/2 + LEG/2.
+            // This is a negative value (e.g. -155).
+            // Angle Iron Origin Z is PLATFORM_ANGLE_Z_OFFSET.
+            // Angle Iron X is distance DOWN from Origin.
+            // World Z = Origin Z - Angle_X.
+            // Angle_X = Origin Z - World Z.
+            // Angle_X = PLATFORM_ANGLE_Z_OFFSET - bolt_y.
+            
+            // Substitute PLATFORM_ANGLE_Z_OFFSET = corner_y - width/2 + LEG.
+            // Substitute bolt_y = corner_y - width/2 + LEG/2.
+            // Angle_X = (corner_y - width/2 + LEG) - (corner_y - width/2 + LEG/2).
+            // Angle_X = LEG - LEG/2 = LEG/2.
+            
+            x_pos = PLATFORM_ANGLE_LEG/2;
+            
+            for (z_pos = [z_pos_1, z_pos_2]) {
+                translate([x_pos, PLATFORM_ANGLE_THICK/2, z_pos])
+                rotate([0, 90, 0]) // Align with X axis
                 cylinder(d=angle_bolt_hole_dia, h=PLATFORM_ANGLE_THICK + 10, center=true, $fn=24);
             }
 
             // Deck Holes (Middle) - Vertical Holes through Horizontal Leg (Leg 2)
             // Leg 2 is along Y. Normal X. Holes along X.
             // 2 bolts upward connecting to the platform itself
-            // Centered on length
-            center_z = height / 2;
-            for (z_pos = [center_z - PLATFORM_SIDE_DECK_BOLT_SPACING/2, center_z + PLATFORM_SIDE_DECK_BOLT_SPACING/2]) {
+            // Symmetrical from end to end
+            // Offset from ends: PLATFORM_SIDE_DECK_BOLT_END_OFFSET
+            // If not defined, use 1/4 length or similar.
+            // Let's use a fixed offset from ends.
+            deck_bolt_offset = 50; // 50mm from ends
+            for (z_pos = [deck_bolt_offset, height - deck_bolt_offset]) {
                 translate([PLATFORM_ANGLE_THICK/2, PLATFORM_ANGLE_LEG/2, z_pos])
                 rotate([0, 90, 0]) // Align with X axis
                 cylinder(d=angle_bolt_hole_dia, h=PLATFORM_ANGLE_THICK + 10, center=true, $fn=24);
@@ -2464,13 +2554,9 @@ module platform_angle_iron(length=0, is_side=false) {
             // Transverse Angle Iron
             // Deck Holes only
             // 2 bolts: Near ends
-            center_z = height / 2;
             // Note: Transverse angle iron logic is handled by platform_transverse_angle module above
             // This else block might be unused if platform_transverse_angle is used instead
             // But if it IS used, we should update it too.
-            // However, the assembly calls platform_transverse_angle for transverse angles.
-            // So this block is likely dead code or for a different configuration.
-            // I will leave it as is or update it to match just in case.
             for (z_pos = [PLATFORM_TRANSVERSE_BOLT_END_OFFSET, height - PLATFORM_TRANSVERSE_BOLT_END_OFFSET]) {
                 translate([PLATFORM_ANGLE_THICK/2, PLATFORM_ANGLE_LEG/2, z_pos])
                 rotate([0, 90, 0]) // Align with X axis
@@ -2504,8 +2590,8 @@ module folding_platform_assembly(fold_angle=90) {
         // Bracket Thickness is assumed to be PLATE_1_4_INCH (6.35mm).
         // Angle Iron Vertical Leg (Outer Face) should be at Bracket Inner Face.
         // Bracket Inner Face X = PLATFORM_PIVOT_X - PLATE_1_4_INCH/2.
-        // So Angle Iron X = PLATFORM_PIVOT_X - 3.175.
-        angle_iron_x_from_center = PLATFORM_PIVOT_X - 3.175;
+        // So Angle Iron X = PLATFORM_PIVOT_X - PLATFORM_SIDE_GAP.
+        angle_iron_x_from_center = PLATFORM_PIVOT_X - PLATFORM_SIDE_GAP;
 
         // Shift platform forward by 0.5 inches (12.7mm)
         shift_y = 0;
@@ -2748,7 +2834,7 @@ module folding_platform_assembly(fold_angle=90) {
             color("DarkSlateGray")
             translate([bracket_x, pivot_y, pivot_z])
             rotate([fold_angle, 0, 0])
-            rotate([0, -90, 0])
+            rotate([0, -90, 0]) // Reverted rotation: X->Z (Up), Y->Y (Back), Z->-X (Side)
             linear_extrude(height=PLATFORM_THICKNESS, center=true)
             projection(cut=true)
             platform_pivot_bracket();

LifeTrac-v25/mechanical_design/openscad/lifetrac_v25_params.scad

@@ -191,7 +191,8 @@ PLATFORM_PIVOT_X = _inner_wall_x - PLATE_1_4_INCH/2;
 // PLATFORM_WIDTH calculated to fill distance between L plates (Pivot Brackets) with 1/8" gap
 // Pivot Bracket Inner Face = PLATFORM_PIVOT_X - PLATFORM_THICKNESS/2
 // Gap = 1/8 inch = 3.175mm
-PLATFORM_WIDTH = 2 * (PLATFORM_PIVOT_X - PLATFORM_THICKNESS/2 - 3.175);
+PLATFORM_SIDE_GAP = 3.175;
+PLATFORM_WIDTH = 2 * (PLATFORM_PIVOT_X - PLATFORM_THICKNESS/2 - PLATFORM_SIDE_GAP);
 
 // --- Pivot bracket dimensions ---
 PLATFORM_BRACKET_WIDTH = 100;   // Width of pivot bracket plate (mm)
@@ -215,6 +216,10 @@ PLATFORM_TRANSVERSE_BOLT_END_OFFSET = 38.1; // 1.5" offset from ends for transve
 PLATFORM_SIDE_DECK_BOLT_SPACING = 150;  // Spacing for side angle deck bolts (mm)
 PLATFORM_EDGE_MARGIN = 12.7;            // 1/2" margin from deck edge to angle iron (mm)
 
+// --- Bolt Offsets for Collision Avoidance ---
+deck_bolt_offset = 50;                  // Distance from ends for deck bolts (mm)
+pivot_bolt_offset = 40;                 // Distance from ends for pivot bracket bolts (mm) - Increased to ensure engagement with angle iron
+
 // --- Anti-slip pattern ---
 PLATFORM_ANTISLIP_HOLE_DIA = 15;   // Diameter of anti-slip holes (mm)
 PLATFORM_ANTISLIP_SPACING = 80;    // Spacing between anti-slip holes (mm)

LifeTrac-v25/mechanical_design/openscad/parts/platform_deck.scad

@@ -28,9 +28,13 @@ module platform_deck() {
     bolt_hole_dia = PLATFORM_BOLT_DIA + PLATFORM_BOLT_CLEARANCE;
 
     // Angle iron attachment positions (X coordinates)
-    deck_half_width = width / 2;
-    arm_margin = 35;
-    arm_x_pos = min(PLATFORM_PIVOT_X, deck_half_width - arm_margin);
+    // Aligned with the center of the angle iron leg (Leg 2)
+    // Angle Iron Center X = PLATFORM_PIVOT_X - PLATFORM_SIDE_GAP (Gap/2)
+    // Hole Offset from Center = PLATFORM_ANGLE_LEG/2 (Inward)
+    // So Hole X = (PLATFORM_PIVOT_X - PLATFORM_SIDE_GAP) - PLATFORM_ANGLE_LEG/2
+    
+    angle_iron_center_x = PLATFORM_PIVOT_X - PLATFORM_SIDE_GAP;
+    arm_x_pos = angle_iron_center_x - PLATFORM_ANGLE_LEG/2;
     arm_x_left = -arm_x_pos;
     arm_x_right = arm_x_pos;
 
@@ -39,12 +43,23 @@ module platform_deck() {
         cube([width, depth, thickness], center=true);
 
         // Anti-slip hole pattern
-        for (x = [-width/2 + PLATFORM_ANTISLIP_EDGE_MARGIN : 
-                   PLATFORM_ANTISLIP_SPACING : 
-                   width/2 - PLATFORM_ANTISLIP_EDGE_MARGIN]) {
-            for (y = [-depth/2 + PLATFORM_ANTISLIP_EDGE_MARGIN : 
-                       PLATFORM_ANTISLIP_SPACING : 
-                       depth/2 - PLATFORM_ANTISLIP_EDGE_MARGIN]) {
+        // Symmetrical grid calculation
+        // Calculate number of holes that fit within margins
+        avail_x = width - 2 * PLATFORM_ANTISLIP_EDGE_MARGIN;
+        num_x = floor(avail_x / PLATFORM_ANTISLIP_SPACING);
+        
+        avail_y = depth - 2 * PLATFORM_ANTISLIP_EDGE_MARGIN;
+        num_y = floor(avail_y / PLATFORM_ANTISLIP_SPACING);
+        
+        // Center the grid
+        start_x = - (num_x * PLATFORM_ANTISLIP_SPACING) / 2;
+        start_y = - (num_y * PLATFORM_ANTISLIP_SPACING) / 2;
+        
+        for (i = [0 : num_x]) {
+            x = start_x + i * PLATFORM_ANTISLIP_SPACING;
+            for (j = [0 : num_y]) {
+                y = start_y + j * PLATFORM_ANTISLIP_SPACING;
+                
                 // Skip holes that would interfere with bolt hole areas
                 // Expanded exclusion zones for new transverse angles
                 if (!(abs(x - arm_x_left) < 50) && 
@@ -61,19 +76,40 @@ module platform_deck() {
 
         // Left angle iron mounting holes (Side Angle)
         // 2 bolts upward connecting to the platform itself
-        for (y_pos = [-PLATFORM_SIDE_DECK_BOLT_SPACING/2, PLATFORM_SIDE_DECK_BOLT_SPACING/2]) {
+        // Symmetrical from ends of the side angle iron.
+        
+        // Replicate assembly logic to find World Y positions
+        _deck_pivot_y = PLATFORM_BRACKET_WIDTH/2;
+        _deck_far_y = -(PLATFORM_DEPTH - PLATFORM_BRACKET_WIDTH/2);
+        _front_angle_corner_y = (_deck_pivot_y - PLATFORM_EDGE_MARGIN) - PLATFORM_ANGLE_LEG;
+        _rear_angle_corner_y = (_deck_far_y + PLATFORM_EDGE_MARGIN) + PLATFORM_ANGLE_LEG;
+        _gap = 12.7;
+        _side_angle_start_y = _front_angle_corner_y - _gap;
+        _side_angle_end_y = _rear_angle_corner_y + _gap;
+        
+        // Bolt Offset from Ends = 50mm (matching angle iron definition)
+        _bolt_offset = 50;
+        _bolt_1_world_y = _side_angle_start_y - _bolt_offset;
+        _bolt_2_world_y = _side_angle_end_y + _bolt_offset;
+        
+        // Convert World Y to Deck Y
+        // Deck Y = -World Y - Shift
+        // Shift = PLATFORM_DEPTH/2 - PLATFORM_BRACKET_WIDTH/2
+        _shift = PLATFORM_DEPTH/2 - PLATFORM_BRACKET_WIDTH/2;
+        
+        _bolt_1_deck_y = -_bolt_1_world_y - _shift;
+        _bolt_2_deck_y = -_bolt_2_world_y - _shift;
+        
+        for (y_pos = [_bolt_1_deck_y, _bolt_2_deck_y]) {
             translate([arm_x_left, y_pos, 0])
             cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
-        }
-        
-        // Right angle iron mounting holes (Side Angle)
-        for (y_pos = [-PLATFORM_SIDE_DECK_BOLT_SPACING/2, PLATFORM_SIDE_DECK_BOLT_SPACING/2]) {
+            
             translate([arm_x_right, y_pos, 0])
             cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
         }
 
         // Transverse Angle Holes (Front and Rear)
-        // 2 bolts per angle: Near ends (aligned with side rails)
+        // 3 bolts per angle: Near ends and Center
         // Angle irons are positioned with outside edge at PLATFORM_EDGE_MARGIN from deck edge.
         // Bolt holes should be centered on the angle iron leg.
         transverse_bolt_y_margin = PLATFORM_EDGE_MARGIN + PLATFORM_ANGLE_LEG / 2;
@@ -86,7 +122,7 @@ module platform_deck() {
         transverse_bolt_x = arm_x_pos - (PLATFORM_TRANSVERSE_GAP + PLATFORM_TRANSVERSE_BOLT_END_OFFSET);
 
         for (y_pos = [-transverse_bolt_y, transverse_bolt_y]) {
-            for (x_pos = [-transverse_bolt_x, transverse_bolt_x]) {
+            for (x_pos = [-transverse_bolt_x, 0, transverse_bolt_x]) {
                 translate([x_pos, y_pos, 0])
                 cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
             }

LifeTrac-v25/mechanical_design/openscad/parts/platform_pivot_bracket.scad

@@ -36,8 +36,23 @@ module platform_pivot_bracket() {
     // Corner radius - using width/2 to maintain constant width and avoid pinching
     corner_radius = width / 2; 
 
-    bolt_1_x = PLATFORM_SIDE_BOLT_START; // 20mm
-    bolt_2_x = PLATFORM_SIDE_BOLT_START + PLATFORM_SIDE_BOLT_SPACING; // 90mm
+    // Bolt positions
+    // Moved to Leg 2 (Horizontal in File X, Vertical in Assembly Z)
+    // This places bolts on the "bottom" leg relative to the L-shape in 2D view
+    
+    // Y position is constant (centered on Leg 2)
+    // Leg 2 is centered at corner_y. Width is width.
+    // We want bolts in the "bottom half" of the leg width.
+    // Bottom edge is corner_y - width/2.
+    // Bolt Y = Bottom Edge + LEG/2.
+    bolt_y = corner_y - width/2 + PLATFORM_ANGLE_LEG/2;
+    
+    // X positions (distributed along Leg 2)
+    // Leg 2 extends from X=0 to X=PLATFORM_BRACKET_LENGTH - width/2
+    // We place bolts at pivot_bolt_offset from each end of this span
+    leg2_length = PLATFORM_BRACKET_LENGTH - width/2;
+    bolt_x_1 = pivot_bolt_offset;
+    bolt_x_2 = leg2_length - pivot_bolt_offset;
 
     // Hole diameters
     pivot_hole_dia = PLATFORM_PIVOT_PIN_DIA + PLATFORM_BOLT_CLEARANCE;
@@ -46,7 +61,7 @@ module platform_pivot_bracket() {
 
     difference() {
         union() {
-            // Vertical Leg (Pivot to Corner)
+            // Vertical Leg (Pivot to Corner) - Along Y
             hull() {
                 // Pivot position
                 translate([0, pivot_y, 0])
@@ -57,7 +72,7 @@ module platform_pivot_bracket() {
                 cylinder(r=corner_radius, h=thickness, center=true, $fn=48);
             }
 
-            // Horizontal Leg (Corner to End)
+            // Horizontal Leg (Corner to End) - Along X
             hull() {
                 // Corner position
                 translate([0, corner_y, 0])
@@ -78,16 +93,11 @@ module platform_pivot_bracket() {
         cylinder(d=lock_hole_dia, h=thickness + 4, center=true, $fn=32);
 
         // Bolt holes
-        // Positioned 1 inch (25.4mm) from the bottom edge of the bracket
-        // Bottom edge Y = corner_y - width/2
-        // Bolt Y = Bottom edge Y + 25.4
-        bolt_y = (corner_y - width/2) + 25.4;
-        
-        translate([bolt_1_x, bolt_y, 0])
-        cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
-        
-        translate([bolt_2_x, bolt_y, 0])
-        cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
+        // Positioned along Leg 2 (X axis)
+        for (bx = [bolt_x_1, bolt_x_2]) {
+            translate([bx, bolt_y, 0])
+            cylinder(d=bolt_hole_dia, h=thickness + 4, center=true, $fn=32);
+        }
     }
 }