Introduction: Strata Bench / Design / Part 1 of 3
This project is an exploration into form and workflows - a combination of using manual hand skills, computer aided design (CAD), and digital fabrication - to create a sculptural and functional bench made from stacked and carved plywood. My sculptures are typically fairly complex and organically shaped forms, which can be very challenging to draw from scratch in a CAD program. I greatly appreciate the power of using a computer for design - but designing within the boundaries of a program can be limiting, and I find working with my hands to be a very physically gratifying process. The Strata Bench project gives equal emphasis to hands-on analog design techniques with the benefits digital design processes to create a human scale, highly crafted, functional plywood sculpture.
This is Part 1 of 3 : the Design Process. This involves sketching design ideas, hand sculpting a clay model, and using 123D Catch to scan the model to create a 3D mesh that can be digitally scaled, modified, and sliced into parts in a computer program.
Part 2 covers how to make a Scale Model of the design, using 123D Make to slice the digital model into dimensioned layers, exporting the 2D part layout, laser cutting plywood parts, and assembling and carving the scale model. Making a scale model is a great way to evaluate and modify the design before starting full scale fabrication.
Part 3 takes the design into the Fabrication process. This includes making design modifications based on the scale model, using a water jet machine to cut out the full scale plywood parts, gluing up the parts into sections using a vacuum bag and clamps, and shaping the whole form into a smooth, finished surface using grinders and hand tools.
Step 1: Sketch Your Ideas
There is no right or wrong to drawing, you just have to go all in. Not all drawings are going to be beautiful. What I find most enjoyable about drawing my ideas is that I can think through the form and the construction while I'm sketching. I had a very general idea for this sculpture, inspired in part by a trip to Death Valley. Looking at all the rock formations and geologic strata shaped by wind and water was a huge influence in this design. I also wanted it to be somewhat functional as a bench, so that was in the back of my mind as well.
I love blue pencil! I drew several pages of sketches, some really rough, some more refined, some in several perspectives. Adding contour lines and shading can be helpful to see the shape as a 3D object. Once I've got enough to go on, I'll switch to sculpting in modeling clay.
Step 2: Sculpt a Clay Model
Sculpting with modeling clay I find to be one of the most satisfying parts of the process... I used plasticine modeling clay, an oil based clay that will not dry out. Its not too soft, holds shape well, is easily modified and formed, not too stiff, yet it also holds an incredible amount of detail and texture. It is sold in 2 lb blocks at most art supply stores or online. I also had a set of wax sculpting and dental tools (also purchased at and art store) on hand, which can be helpful for detailing and smoothing.
I ended up made 4 or 5 different models before coming to one I really liked. The first few I felt were too symmetrical and looked too much like a chair. I wanted the design to suggest sitting and invite the body, but be more abstract and asymmetric to keep visual interest.
Step 3: From Physical to Digital
This project was the result of an Artist Residency at the Pier 9 Workshop, where the Instructables staff and a number of other Autodesk-owned companies are housed. Through the residency, I was introduced 123D Apps - they make a collection of free, user-friendly apps for 3D modeling. This step uses 123D Catch to scan the clay model, and in Part 2, I'll use 123D Make to slice the mesh model into a 2D part layout. What I love about these apps is that they cut out a lot of screen time by making somewhat complex modeling functions a lot easier. The best part is that I was able to work directly with some of the 123D Apps team to problem-solve and give feedback on the apps - Thank you Christian and Rob for all your help!
123D Catch is a free app that lets you create 3D scans of physical objects. After downloading the app, I set up the clay bench model on a stool with a newsprint background - the app uses irregular patterns to register the photos. I also added marks to the clay model. I took a series of about 20 sequential photographs in small increments around the clay model, from a low angle, mid-angle, and high-angle - a total of about 60 photos. Upload the photos to the 123D catch cloud and the program will stitch together the images and create a 3D mesh model from the photos. The model can be mended in the mesh editing in the web app. Its pretty simple to use! Here are some tips for getting a more successful Catch.
- Use newspaper with an irregular pattern for the background.
- Plain, reflective, and transparent surfaces will not work.
- Get close up and fill the frame with your object.
- Even lighting is helpful.
- Don't move the object when taking the photographs. Put it on a stationary platform that you can walk all the way around, and keep the camera at a relative distance for all the photos.
Once I had a successful mesh model from the Catch scan, I was ready to make a scale model out of plywood, so I could evaluate and modify the design before going into full scale fabrication. See how I made a Scale Model in Strata Bench / Part 2 of 3.