The willow school has a limited amount of seating, and it is quickly taken up during lunch, leaving many students sitting on floors. We wanted to decorate the hallways with cool looking wooden chairs that are also fully functional and can be used by the students of the Willow School. I was assigned for a school project to make a chair out of a 4ftx4ft piece of plywood using a CNC machine. \

The model inspiration comes from an image off of Pinterest but is completely made by me and no other information was taken from the site besides what you see from the image. I understood this would be slightly difficult because of how I needed to not only figure out the measurements on my own, but also change them to fit with my limitation of a 4x4 foot piece of wood.

Supplies

4ft x 4ft plywood
nails
CNC (To cut)
Sand paper

Step 1: Research

First step was research in which I found a small amount of chairs that seemed like something that I wanted to build. Most chairs not only seemed complicated, but also just not the shape or design I wanted. I wanted something simple but also sort of modern while utilizing the least amount of pieces. I ended up picking this chair because of how simple it is but also how modern and cool it looks. The simple one board in the back extends out to make a leg and a back rest while two other boards create the side legs and one more board laying across the backboard and the legs to make the seat.

Step 2: 3d Modeling

Since I don't know the measurement of the pieces I had to first create a fusion model that resembled the chair I wanted to make. I sketched the pieces out on paper and then created sketches in fusion to resemble these pieces.

Every piece had to be extruded to 19.05mm so that it could be the proper thickness (same as the wood). This also helped me understand the angles of he backboard and the legs. As you can see, it's not exactly the same as the chair in the original picture, but it close enough and will properly give me pieces.

One problem I came across was that in fusion, this model came out as one body so I couldn't separate it. I did some research to see if I could split it up, but after not being able to find anything I simply settled on taking measurements from the model and then remaking the pieces in another project so that they can be cut (The second picture)

Step 3: Carbide Create (Scale Chair)

Next, I take my sketch file of the separate pieces of my chair and throw it into carbide create. I use carbide create to bridge the gap between a Fusion Sketch and a model chair. Carbide create gives the CNC machine the proper directions it needs to have the pieces be cut.

For this I needed to create a small, scaled down chair so that I could see how it looks and fits together. A major factor in this, is the wedge of the legs into the main body of the chair. Even though this is going to be thoroughly put together, I wanted to make sure this wedge was also tight and fit. It's perfect to use a scaled down model of your chair so that less material is wasted and it takes a lot less time to cut.

I ran into a a problem though, when putting the dxf file into carbide create. It seemed to be a side profile picture of my pieces instead of an over view (first picture above). After asking around I figured out I needed to project my arrangement to create a top view sketch.

I then imported this sketch into Carbide Create to make my tool path, which wasn't too difficult since my chair doesn't have any holes so the tool path is all on one layer. After making the tool path I threw it onto a flashdrive and plugged it into the CNC machine.

Step 4: Construction and Testing

Constructing my chair is rather simple, as both of the legs just wedge into the backboard and I use glue to keep the pieces in place. I also had to sand down an angle at the edge of both the backboard and seat so that they could be glued together at an angle and so that the backboard go be angled back at the angle it's at in the model. This is because the CNC machine couldn't cut at the

Testing can prove very difficult, mainly because the first product is almost never the final product. Pieces may be too small to fit, or even worse, the structure of your chair can't support weight. Either way it can be very discouraging, but is simply part of the design process. This is also one of the downsides to creating a scaled down model of the chair, because although we can simulate the weight, it's impossible to get an accurate example of how the chair will perform under the weight of a human.

Note: Missing pictures because chair hasn't been cut yet.