OpenSCAD: The Programmer's Solid 3D CAD Modeller

Post by bvrmn » Sun, Sep 15, 2024, 1:59 PM UTC

timonoko wrote: post #108

bvrmn wrote: post #101

I don't say it's impossible but I believe it's quite near to impossible for most of OpenSCAD users to model this relatively simple drawing[1]. It's a breeze in CAD with constraint solver. Also it's viable in code-first systems with access to shape coordinates (build123d) using only construction geometry and projections. OpenSCAD requires hard trigonometry and math skills to pull it out. OpenSCAD has amazing community…

13 minutes. And I am very much at the lower end of the CAD skill scale $fn=100; difference(){ union(){ cylinder(d=55,h=60); translate([125,0,0]) cylinder(d=30,h=32); linear_extrude(11) polygon([[0,25],[125,15],[125,-15],[0,-25]]); translate([0,5.5,0]) rotate([90,0,0]) linear_extrude(11) polygon([[0,50],[125,40],[125,0],[0,0]]); } cylinder(d=35,h=70); translate([125,0,0]) cylinder(d=20,h=40); translate([110,8,98]) rot…

Post by WillAdams » Sun, Sep 15, 2024, 2:09 PM UTC

lucasoshiro wrote: post #117

OpenSCAD of course is not as powerful as other tools, but it has a lot of pros (depending on what you consider a pro): - Free, unlike other tools such as Fusion or SolidWorks - Open Source, unlike other tools such as Tinkercad or OnShape - 100% based on a programming language: compared to others is like comparing plain HTML with HTML + JS - Parameterizable (as a consequence of being based on a programming language),…

Post by bvrmn » Sun, Sep 15, 2024, 2:13 PM UTC

timonoko wrote: post #108

bvrmn wrote: post #101

I don't say it's impossible but I believe it's quite near to impossible for most of OpenSCAD users to model this relatively simple drawing[1]. It's a breeze in CAD with constraint solver. Also it's viable in code-first systems with access to shape coordinates (build123d) using only construction geometry and projections. OpenSCAD requires hard trigonometry and math skills to pull it out. OpenSCAD has amazing community…

13 minutes. And I am very much at the lower end of the CAD skill scale $fn=100; difference(){ union(){ cylinder(d=55,h=60); translate([125,0,0]) cylinder(d=30,h=32); linear_extrude(11) polygon([[0,25],[125,15],[125,-15],[0,-25]]); translate([0,5.5,0]) rotate([90,0,0]) linear_extrude(11) polygon([[0,50],[125,40],[125,0],[0,0]]); } cylinder(d=35,h=70); translate([125,0,0]) cylinder(d=20,h=40); translate([110,8,98]) rot…

    r1, r2 = 55/2, 30/2
    cd = 125

    # construct rib profile, start with slope and oversized arc
    # reposition line to be constrained on arc center height and Y axis
    l = build_line(O, op_line(-8, 30, name='l1'), op_arc(30, -90, name='a1'))
    l.move(Vector(77-r1*2, 0) - l.a1.center_point)
    ip, = intersections(l.l1, Axis.Y)
    l.move(Y(50 - ip.Y))

    # Now we know first arc center and could project it on a second arc center
    # axis with known distance and get tangent point. Use point to trim oversized fist arc
    # and create second tangent arc.
    a2c = point_on_axis_with_dist(l.a1.center_point, Axis.X.offset((0, 66+32)), 66+30)
    ip, = intersections(l.a1, axis_from_points(l.a1.center_point, a2c))
    l.append(op_trim(ip), op_arc(to=(a2c.X, 32)), XA(cd-r1), YA(0), (l.s.X, 0)).close()

    # Convex hull of base cylinders would have correct tangents
    base_sk = make_hull((X(cd) * Circle(r2) + Circle(r1)).edges())

    # Contruct final part
    obj = extrude(X(r1) * RX(90) * l.face(), 11/2, both=True) + extrude(base_sk, 11)
    obj += Cylinder(r1, 60, align=A.d)
    obj += X(cd) * Cylinder(r2, 32, align=A.d)
    obj -= Cylinder(35/2, 60, align=A.d)
    obj -= X(cd) * Cylinder(20/2, 32, align=A.d)

Post by throwgfgfd25 » Sun, Sep 15, 2024, 2:30 PM UTC

timonoko wrote: post #126

bvrmn wrote: post #121

Earlier quoted context omitted.

I appreciate your attempt and time spent. It's an amazing showcase how simple things could be easily expressed in OpenSCAD. But the part in question sadly is not that simple. All tangents are wrong.

Erh? Are you complaining about some minor adjustment, so that lines are not meeting the curves smoothly? I did not even understand what TANGENT means, cause I know much nothing about CAD.

Post by LiamPowell » Sun, Sep 15, 2024, 2:38 PM UTC

timonoko wrote: post #126

bvrmn wrote: post #121

Earlier quoted context omitted.

I appreciate your attempt and time spent. It's an amazing showcase how simple things could be easily expressed in OpenSCAD. But the part in question sadly is not that simple. All tangents are wrong.

Erh? Are you complaining about some minor adjustment, so that lines are not meeting the curves smoothly? I did not even understand what TANGENT means, cause I know much nothing about CAD.