Laser-Cut Tree Construction Kit

I wanted to make a lego-like kit with pieces that could be assembled to create a tree sculpture. The press-fit design allows the pieces to be joined using only friction, without any other adhesive or joinery techniques. The components were designed in Fusion360, then exported to adobe illustrator and laser cut.

Software:

• Fusion360 + (Autodesk adobe illustrator export extension)
• adobe illustrator

Materials:

• Birch wood

Tools:

• Caliper

I first sketched my idea with pen and paper to form the general shape of my design. I then broke it down into components and sketched those, making sure to label which dimensions were the same. In my above sketch 'w' represents the width of my "notches" where the pieces will be connected.

I next translated my rough sketches into 2D sketches in Fusion360. Using interpolation curves, I drew an enclosed form to represent each piece I wanted to cut, starting with the tree trunk.

I finished the sketch and extruded it to create a 3D solid representation of the final piece in wood. To do this, I measured the width of my birch plywood sheet to be 0.25in, recorded that value as "materialThickness" to be used as a recurring parameter, and extruded the sketch that distance to create a new body.

The implementation of the press-fit design for this construction kit was done using notches on connecting pieces that allow them to fit together snugly. The pieces are designed to fit together with perpendicular angles, so the notch width was set to the material thickness. To create these notches I created a sketch representing the notch on a plane perpendicular to the piece. I then extruded the notch sketch into the piece body to "cut" the notch out, as shown above. By lining up my sketched pieces I was able to create construction lines showing how deep the notches needed to be.

Once I had all my pieces created, I used the adobe illustrator extension to export each component separately as a .dfx file. I used two small pieces to test the kerf needed for them to fit tightly; I initially set it to 0.35mm which was way too tight, then reduced it to 0.2mm for a second test. These still felt a little snug, so I changed my final kerf allowance to 0.18mm. I then imported all the components into adobe, arranged the pieces close together to minimize material use, and laser cut the file out of birch plywood.

I assembled my pieces in a few different ways before deciding on the final orientation I liked best. One thing I like about this design is it's easy to rearrange however you like, as it's press-fit and doesn't require glue.

An idea I had after viewing the final product was to make this into a jewelry, or earring holder by adding small holes to the leaf pieces.