Computer-controled machining

Assignment #8
Computer controled machining | Stool

PHASE 1 |Design 3D

I always dreamt of designing a piece of furniture! And this was my first stool design ever. This design is inspired by our lunch table chair which i fancy because of its sofisticated lokking and cool design. Though, I made a lot of changes in the design

Process:

1- Sketching on paper with dimentions:

From several sides (top, back, front, and side)

2- Design each part of your design separately

I used a technique that works well with Sketch Up, cutting the shape from a block.

3- Final step- Prepare the machining file:

I made the 2D design in order to be cut on the Shopbot, transforming the 3D design into 2D.

Design

using Sketch Up

PHASE 2 |Machining

Using the Shopbot
Dimensions of the cut space (96cm*120cm)

At the start I faced some problems with the file format and scale, but after adjustments I have been able to cut all stool parts in 15 minutes of machining. It's important to make the most out of the material you have and avoid the waste material as much as possible.

To prepare the machining file, all the inner parts are grouped as one process and then the outter parts are cut later in order to keep a stable cutting surface for the end mill to cut, passing from 2 to 3 times depending on the end mill type and the depth of the material. In this case, The end mill passed two times cutting in a sheet with thickness 12 mm.

The Shopbot CNC machine is loud so it is better to wear safety ear muffs.

PHASE 3 |Assemble

I learned alot while assembling the stool, concerning the design, the jointing technique, and the material (MDF) and its thickness.
When designing anything 'BIG', you need to keep in mind whether the material and its thickness is compatible with your design or not, or you will end of with either a fragile piece or a very heavy one.

In this case, the stool would have been more stable if the material was thicker, from 16 mm to 18 mm for instance.