// -*- C -*- // use shell thickness 1.50 // use fill density 40% include tube_dia = 27.5 + 1.625; lock_w = 42.5 + 0.5; lock_d = 28.0 + 0.5; main_h = 45.0; backflange_d = 12; backflange_hole_dy = -1; lockshaft_dia = 14.35; cliprecess_h = 16; total_h = 45; back_gap = 12.5; main_th = 3.50; tube_th = 4.00; midweb_d = 3; clip_th = 3.5; clip_gap = 2.5; clip_d = 22.0; mountscrew_dia = 4 + 0.5; clipbolt_dia = 5 + 0.6; mountscrew_washer = 10; backflange_th = 4.5; $fn=50; join_cr = 9; tube_rear_extra_th = 1; divide_shaft_w = 1.75; divide_shaft_l = 1.5; divide_head_dx = 1.75; divide_head_th = 1.5; divide_gap = 0.50; divide_heads = 2; divide_angle = 26; divide_fudge_r = 4.75; divide_around = 3.5; backflange_angle = 20; // calculated lockshaft_r = [1, 1] * lockshaft_dia / 2; front_th = main_th; tube_or = tube_dia/2 + tube_th; back_ohw = back_gap/2 + backflange_th; backflange_ymin = tube_dia/2 + backflange_d; lock_0y = tube_dia/2 + lock_d/2 + midweb_d; lock_0x = lock_w/2 - lock_d/2; lock_0 = [lock_0x,lock_0y]; lock_or = [lock_w, lock_d]/2 + [front_th,front_th]; module oval(sz){ // sz[0] > sz[1] xr = sz[0]; yr = sz[1]; hull(){ for (sx=[-1,+1]) { translate([sx * (xr-yr), 0]) circle(r=yr); } } } module JoinCircs(jr){ // http://mathworld.wolfram.com/Circle-CircleIntersection.html R = tube_or + join_cr; r = lock_or[1] + join_cr; d = dist2d( [0,0], lock_0 ); x = (d*d - r*r + R*R) / (2*d); y = sqrt( R*R - x*x ); echo(lock_0x, lock_0y, R,r, d, x,y); for (m=[0,1]) { mirror([m,0]) { rotate(atan2(lock_0y, lock_0x)) { translate([x,-y]) circle(r= jr); } } } } module DivideHook(){ ////toplevel w = tube_th/2; d = divide_gap; translate([-1,0] * (w + d + w)){ for (sx=[-1,+1]) translate([-(w + w+d) * sx, 0]) circle(r= w); difference(){ circle(r = 3*w + d); circle(r = w + d); translate([-10*w, -10*w]) square([20*w, 10*w]); } } } module DivideCut(){ w = tube_th/2; d = divide_gap; br = tube_dia/2 + tube_th; difference(){ offset(r=divide_gap) DivideHook(); DivideHook(); translate([-2*w,0]) mirror([0,1]) square([4*w, 4*w]); } } module DivideCutB(){ w = tube_th/2; d = divide_gap; br = tube_dia/2 + tube_th; intersection(){ translate([br - tube_th/2,0]) { difference(){ circle(r=br + d); circle(r=br); } } translate([-2*w, 0]) mirror([0,1]) square(4*w); } } module DivideSurround(){ w = tube_th/2; d = divide_gap; offset(r= w*2) { hull() { DivideCut(); translate([-(4*w + 2*d), 8*w]) circle(r=w); } } } module DivideInPlace(){ rotate([0,0, -divide_angle]) translate([ -tube_dia/2 -tube_th/2, 0]) children(); } module MainPlan(){ ////toplevel difference(){ union(){ difference(){ union(){ hull(){ for (t=[0, tube_rear_extra_th]) translate([0, -t]) circle(r = tube_or); } rotate([0,0, backflange_angle]) translate([-back_ohw,0]) mirror([0,1]) square([back_ohw*2, backflange_ymin]); translate([0, lock_0y]){ oval(lock_or); } hull(){ JoinCircs(0.01); polygon([[0,0], lock_0, [-lock_0[0], lock_0[1]]]); } } rotate([0,0, backflange_angle]) translate([-back_gap/2,1]) mirror([0,1]) square([back_gap, backflange_ymin+2]); JoinCircs(join_cr); } DivideInPlace() DivideSurround(); } translate([0, lock_0y]){ oval([lock_w/2, lock_d/2]); } circle(r = tube_dia/2); DivideInPlace() DivideCut(); DivideInPlace() DivideCutB(); } } lockshaft_or = lockshaft_r + [clip_th,clip_th]; cliprecess_ymax = cliprecess_h - lockshaft_r[1]; clip_ymin = cliprecess_ymax - total_h; clip_ogap = clip_gap + clip_th*2; module ClipElevationPositive(){ hull(){ oval(lockshaft_or); translate([0, -lockshaft_or[1] * sqrt(2)]) square(center=true, 0.5); } translate([-lockshaft_or[0], 0]) square([lockshaft_or[0]*2, cliprecess_ymax]); translate([-clip_ogap/2, 0]) mirror([0,1]) square([clip_ogap, -clip_ymin]); } module ClipElevationNegative(){ hull(){ for (y=[0, cliprecess_ymax+1]) translate([0, y]) oval(lockshaft_r); } translate([-clip_gap/2, 1]) mirror([0,1]) square([clip_gap, 2-clip_ymin]); } module ClipElevation(){ difference(){ ClipElevationPositive(1); ClipElevationNegative(0); } } module ExtrudeClipElevation(extra=0){ translate([0, lock_0y + lock_d/2 + clip_d + extra, -clip_ymin]) rotate([90,0,0]) linear_extrude(height= clip_d + extra*2, convexity=100) children(0); } module ThroughHole(r, y, z, x=-50) { translate([x, y, z]) rotate([0, 90, 0]) cylinder(r=r, h=100, $fn=20); } module MountingHoleCylinders(r, x=-50){ for (z=[ 1/4, 3/4 ]) { rotate([0,0, backflange_angle]) ThroughHole( r, -tube_dia/2 -0.5*backflange_d + backflange_hole_dy, total_h * z, x); } } module ThroughHoles(){ MountingHoleCylinders(mountscrew_dia/2); ThroughHole( clipbolt_dia/2, lock_0y + lock_d/2 + clip_d/2 + front_th/2, total_h - cliprecess_h - clip_th - clip_d/2 ); } module MainPositive(){ difference(){ union(){ linear_extrude(height=total_h, convexity=100) MainPlan(); ExtrudeClipElevation() ClipElevationPositive(); } ExtrudeClipElevation(1) ClipElevationNegative(); } } module Bracket(){ ////toplevel difference(){ MainPositive(); ThroughHoles(); } } module TestTopEdge(){ ////toplevel intersection(){ translate([0,0, -total_h]) translate([0,0, 4]) Bracket(); translate([-200,-200,0]) cube([400,400,100]); } } module TestClipBoltHole(){ ////toplevel intersection(){ union(){ translate([0, 0, -5]) Bracket(); translate([-4, lock_0y + lock_d/2 + 1, 0]) cube([8, 4, 1.5]); } translate([-200, lock_0y + lock_d/2 + 0.1]) cube([400, 400, total_h-20]); } } module Demo(){ ////toplevel Bracket(); color("blue") MountingHoleCylinders(mountscrew_dia/2 - 0.1); color("black") MountingHoleCylinders(mountscrew_washer/2, back_ohw + 0.25); } module DivideDemo(){ ////toplevel color("black") translate([0,0,-2]) MainPlan(); color("grey") DivideInPlace() DivideHook(); color("blue") translate([0,0,-4]) DivideInPlace() DivideCut(); } //MainPlan(); //ClipElevationPositive(); //ClipElevation(); //MainPositive(); //%ThroughHoles(); //TestTopEdge(); //TestClipBoltHole(); //Bracket();