DIY Chandelier (The Art of Transforming Object)

Chandelier's are a beautiful dramatic lighting element to your home. Till today many people are fascinated of having chandeliers at their home. Chandelier enhances the appearance of a living room or a dining area, with it's soft, glowing atmospheric similar light.

But, most of the families are unable to afford the rich glowing chandelier's though they wish too have one. Our goal is to make this beautiful chandelier available to every single person who loves to have one at a very reasonable price. We achieve to provide this DIY Chandelier at a reasonable price by using 3D Printing Technology. This Chandelier design is derived from the most famous Kinetic Hoberman Sphere concept.

What is the Hoberman Sphere?

A Hoberman sphere is a kinetic structure patented by Chuck Hoberman that resembles a geodesic dome but is capable of folding down to a fraction of its original size by the scissor-like action of its joints. (Source: Wikipedia)

Inspired by Chuck Hoberman (who is an artist, engineer, architect and inventor), he focuses on the transformable object/structure. Hoberman sphere is one of his most attractive mechanism this sphere, can be expanded almost the double its size. This Structure is slightly modified to utilize in Interior designs. So decided to design and 3D print this.

Things you need to know before this build:

This design Consists of 4 Designs

Links
Cap
Lock Pin (Bolt)
Ring Connectors

We will be using a scissor mechanism to make the sphere expand and contract. Make sure the Dimensions of all the designs to be relative.

Step 1: Things You Need!

First and foremost a 3D printer.
Filament for the printer (White and Black) from solid space (https://solidspace.co.in/).
Solidworks (any other designing software)
Sandpaper (800 and 1000 grade).
Dust Gold Powder paint.
Black Acrylic paint.

Step 2: Link Design

Link's are the essential part of the model which produces a relative motion concerning other parts of the machine.
This is a modified version of Scissor mechanism which converts linear motion to tangential motion.

Step 3: Link Design Process

Based on research, I found out that the Hoberman sphere when expanded doubles the dia compared to the contracted state.
So I decided that I need a Dia of more than 300mm when it expands, so the contracted dia should be more than 150mm. I took the inner Dia(Contracted dia) as 160mm.
Later I divided the circle into 16 parts i.e 360/16 = 22.5 deg.
By taking 3 Consecutive points as the centre of the pivot I designed a link and smoothed the sharp edges to reduce the stress Concentration.
Later I created a reference axis so that it is easy to assemble and study the motion.

Essential steps are shown above with screencast images.

Step 4: Cap Design

This Threaded Cap is designed not only to secure 2 links but also it acts as a pivot and keeps the links parallel.

Step 5: Cap Design Process

This is designed to fit in the hole created in the Link(The hole dia is 8.2mm).
So the outer diameter should be less than 8.2mm. Keeping in mind the printing tolerance the outer dia is selected as 7.25mm.
Thread Dimension: Pitch= 1 mm.
So each revolution makes the piece to travel 1mm. As the depth of the hole is 8mm, the resulted revolution is 8.
For smooth handling, I have filleted the thread head with a fillet radius 0.1mm

Step 6: Lock Pin (Bolt) Design

This Threaded Bolt is designed not only to secure 2 links but also it acts as a pivot and keeps the links parallel.

Step 7: Lock Pin (Bolt) Design Process

This Bolt should perfectly fit the designed cap.
So the pitch of the thread is 1mm and the length of the thread is 8mm.
The hole dia in "Cap" is 5mm so considering the printer tolerance the diameter of the thread is 4.5mm
For smooth handling, I have filleted the thread head with a fillet radius 0.1mm

Step 8: Ring Connector - Cap

These Ring Connectors are connected in the intersection of the spheres. These are designed to connect 2 rings perpendicularly making it a cool sphere.

Step 9: Ring Connector - Bolt

These Ring Connectors are connected in the intersection of the spheres.
These are designed to connect 2 rings perpendicularly making it a cool sphere.

Step 10: Design of Ring Connectors Process

By taking the previously designed Cap and Bolt and modifying the head part.
Basically by taking the dimensions of the Link hole (8.2 mm) and giving it an outer surface of 12mm extrude length.
The thickness of this head part (2mm) + thickness of the link (3.6mm) < Lenght of the bolt (8mm).
Fillet feature is used to reduce stress concentration.
Make sure you save it as a separate file using Save file.

Step 11: 3D Printing Manufacturing

One of the most fascinating invention, which really takes your creation into reality within a couple of hours. These design files are converted to STL file format and are feed to Cura for slicing and converting them to G-CODE which is read by the printer.

The printer used here is Ultimaker Extended 2+.

Using sandpapers and dermal tools (if you have) to post-process it and paint it as per your colour choice. Make sure you print the appropriate amount of links, caps, bolt and Ring connectors.

The whole Sphere requires:

Total Links = 96 pieces
Total Caps and bolts = 96 each
Total Ring Connectors = 12 Pairs (Both Cap and Bolt ring connectors)
Total pieces = 312 pieces!

Step 12: Motion Study and Assembly.

The best part of the whole project was waiting for this. This acts as a validation of your dimensions, which you gave during design.

This has 3 phases:

Virtual assembly in the Solidworks
Motion analysis/study of the design in Solidworks
Once confirmed, print, assemble and enjoy.

Virtual Assembly: This is done in Solidworks, using different mating constraints. Initially drag and drop the link and constrain it to the reference plane and axis. Connect the next link to the previous one. Make sure to follow a zig-zag pattern. i.e connect the 2nd link at the back face of the 1st and connect the 3rd link to the front face of the 2nd link.

Morion Study: In this, you will be applying the forces and see the resultant motion of the assembly. Here the contraction and expansion of the sphere are due to push and pull forces. Virtually apply the force and see how the assembly behaves as desired.

Assembly of 3D printed parts: Once printed and post-processed start assembling similar to the virtual assembly and have a beautiful Hoberman concept Chandelier.

Step 13: Final Outro - Working Model

The working model is attached to a tiny fishing rope that helps us to achieve the kinetic movement by pulling the rope on either side of the model. For future improvements we'll add some electronics stuff to make it autonomous and also add cool IOT features to control the color of the Light and movement of the Chandelier.

Free feel to comment on any improvements and changes. Send me a hifi if you tried to make one : )