Hello everyone!

Well this is my first blog, and today I designed a Chess Bishop using OpenSCAD.

**OpenSCAD** is a free software application for creating solid 3D CAD (computer-aided design) objects. It is a script-only based modeller that uses its own description language; parts can be previewed, but it cannot be interactively selected or modified by mouse in the 3D view. Unlike most other 3D modeling programs like Blender, Sketchup, AutoCAD, or Solidworks, it’s really easy to get started in OpenSCAD.Unlike many 3D modeling or CAD programs, it’s entirely free! Not just free of charge, but it’s open source with a vibrant community.

Basically to use OpenSCAD one should have the knowledge of basic solid shapes, and how it can be combined with other basic solid shapes to make many other complex 3D solid shapes. And that combination result out the desired 3D model.

So, before starting the modeling firstly let’s try to see the basic shapes we can use. And so divide the sections on which we’ll work individually.

The main sections are 1) Head, 2) Neck, 3) Base, 4) Collar

Here are some Basic Coding syntax for OpenSCAD that we’ll be using.

*sphere*“Sphere();”,

*cuboid/cube “*cube([], [] ,[]);”,

*cone/cylinder*“cylinder(, , );”.

• to cut a solid shape from other shape “difference()”.

• for intersection of two solids “intersection()”.

• for mirroring “mirror([x], [y], [z]);” where x, y, z are the coordinates of mirror plane.

• for rotating “rotate([Ø1], [Ø2], [Ø3]);” where Ø1, Ø2, Ø3 are the angles of rotation.

• for positioning the solid “translate([x], [y], [z]);” where x, y, z are the coordinates.

**STEP 1: The Head**

• The head consists of 2 Spheres, 1 Cone, 1 cuboid (will be cut out)

for that the following coding is to be done.

difference() { union() { //Teardrop shape sphere(20); translate([0,0,20*sin(30)]) cylinder(30,20*cos(30),0); //Dollop translate([0,0,30+20*sin(30)]) sphere(5); } rotate([45,0,0]) translate([-20,0,0]) cube([40,5,40]); }

Which will creat a shape something like this

**STEP 2: Neck and Base**

Now its the turn for Neck, and for that

{ //Neck cylinder(120,16,10); //Base cylinder(18,30,22); }

**STEP 3: The Collar**

//Collar translate([0,0,93]) union() { cylinder(3,18,12); mirror([0,0,1]) cylinder(3,18,12); }

which will look something like this

After completion of all the Steps, now we just have to join them all. And the code will look like this

union() { //Head translate([0,0,120]) difference() { union() { //Teardrop shape sphere(20); translate([0,0,20*sin(30)]) cylinder(30,20*cos(30),0); //Dollop translate([0,0,30+sin(30)]) sphere(5); } rotate([45,0,0]) translate([-20,0,0]) cube([40,5,40]); } { //Neck cylinder(120,16,10); //Base cylinder(18,30,22); } { //Collar translate([0,0,93]) union() { cylinder(3,18,12); mirror([0,0,1]) cylinder(3,18,12); } } }

**Note: Dimensions can be varied accordingly. And t****he tangent of cone’s dimensions can be calculated as follows.**

**Start with theta. Then calculate the hypotenuse from r and theta (the red). Then calculate the height of the cone from the hypotenuse. The base radius of the cone is easy to calculate from theta, based on high school math **

Yeah!! So now after all the steps done your Bishop is ready to rock.

Well as a beginner it took me around 90 minutes to understand and structure this Bishop model. Hope you’ll enjoy making your Bishop.

See you in the next Blog, Till then “Namaste!!”.