Tree structure

In this page I’m going to show the design and creation of the tree structure and lightning for the Privacy Seed project.

• Structure
  • Sketching
  • First cardboard prototype (small scale)
  • Second plywood prototype (small scale)
  • Wood structure (large)
• Next steps

Structure

Sketching

During the CNC milling week I started sketching a simplified version of how the tree structure could be built:

Here are some details of the traces carved on the tree trunk:

I also built a 3D model that could be built for testing on smaller scale

I decided to created a small scale cardboard prototype (< 1m height) and then to think about a large scale wood one (< 2m height).

First cardboard prototype (small scale)

I then decided to refine my structure to create a model to laser cut a first prototype:

I struggled a bit finding correct values for cardboard … :) :( … then I ended up with some failed cuts and these values for next time:

By looking at this first prototype I came up with few improvements to do:

1. In the top pressfit part: reduce the circle radius, create easier to fit shapes, make the trunk shape join precisely the circle.
2. In the base element: create a 2 layers base and hide the trunk bottom part under it
3. Increase the differences between the branches shapes
4. Two possible solutions to test how to connect the heart shape: hold in one of the trunk element or hanging from top

Second plywood prototype (small scale)

Before the final presentation I built a new version of the tree structure with 3mm plywood material. This structure is ment to be a 1:5 scale of the final version.

I incorporated in the design the improvements from the first prototype and laser cut the plywood with the same settings used in week3).

In the interest of time I cut 7 identical trunk shapes while in the previous one I had 3+4 different arrangement on the banches on each.
Also to speed up the process I thought to not include the kerf tolerance for the pressfit to have a structure that is easy to mount: Later I regretted this choice because my structure was easily falling apart :)

Here is the result:

The detail of the top circle that will support the led strip and will be covered to hide some cables.

The detail of the bottom plate with a slot to hold the led strip.

The final structure all together with the heart hanging in the middle.

Download models for the tree structure (.zip archive: SolidWorks, STL and Rhino files)

Wood structure (large)

Changes to incorporate:

• LED strip lights on the trunk
• Design a more solid base
• Reinforce structure against vertical axis rotation
• Think a system for easy assembly

…WORK IN PROGRESS…

Next steps

• Design and mill a big wood structure with improvements