The Camping Chair: Welding + Tube Forming

I designed and built this chair for ME203: Design and Manufacturing, the introductory “making” class at Stanford. Students from all different programs work in the “Product Realization Lab”, to create personal projects while learning about the manufacturing process.

My main goal for this challenging project were to create a seat that mimics a camping chair: flexible and comfortable yet grounded and stable. I refined my design, inspired by the Hardoy chair designed in Le Corbusier’s workshop in 1938, yet streamlined for my purposes.

This project required a large amount of scoping and planning before execution because I was required to model my project from scratch with no dimensions or instructions as a guide. While it was quite an extensive process, I created a piece of furniture that suits my exact needs for seat height, support placement and every other feature.

I crafted my chair from mild steel tubing with a natural welded finish, oiled nylon, and reindeer hide, which I took into account when modeling my chair so that it would fit perfectly as a seat. I especially liked the contrast of the two materials texturally as well as the cohesion of the materials aesthetically.

My chair frame involved three processes: tube bending/forming, milling, and TIG welding. I started off by cutting my mild steel tubing and bending it into the correct angles using a hydraulic tube bender. I then cold-set my components to the correct size and angle to reduce error. The next step was to carve out a “fishmouth” onto the ends of my tubing to create a smooth joint where my components joined together for welding—this process required using a milling machine. Lastly, I welded all my components together, carefully cold-setting my pieces as I worked to ensure as much symmetry as possible.

Drafting + Modeling Process

I created an extremely detailed 3D CAD model for this project, complete with angles, measurements, dimensions and referential information. This model was a guide for creating my final project and was extremely useful for ensuring that my final product would function correctly. Below is a simplified view of my CAD model.

Manufacturing Process

After drafting my model, I was ready to begin constructing my chair, I first had to create an MFG Prototype, which would serve as an example of the processes employed during my project. I utilized three separate processes including CNC milling, hydraulic tube bending/forming, and TIG welding. My prototype employs all of these methods and ensured that I could correctly and appropriately operate the machinery in the context of my project.

With this information, I was able to break down the parts and operations necessary for each component. Firstly, I needed to identify the lengths of each piece for the project to ensure all bend-angles are placed at the correct intervals. Since the chair is symmetrical, I needed to make 2 of each part, totaling 8 components.

Next, I created an Order of Operations . This step is crucial because if parts are assembled in an incorrect order, it would be challenging to finish assembly. Ensuring a logical process was essential to completing my project in a timely and precise manner. Due to its 3D nature and the importance of symmetry in my design, it was quite challenging to create an order of operations for this project.

After creating my Order of Operations, I was able to proceed with my project and complete manufacturing. Below are photos of the TIG welding process, which I utilized to weld together the components of my chair.