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ABOUT THE DESIGN
ABOUT THE DESIGN
In Chapter 2, we thoroughly explained the ori-
gins of the AtFAB 5-30 Minute Chair and the
thinking behind its design. The Chair combines
edge-to-edge joinery, symmetrical parts, and
tapered legs to yield an incredibly strong and
sturdy side chair.
BEFORE YOU BEGIN
For this project, you can choose to make the
design as it comes, fabricating a pair of chairs
from a single sheet of plywood. Or you can
learn how to make 2D and 3D CAD modifica-
tions, to tailor your chair’s details or dimen-
sions. This chapter teaches you how to think
through making 2D customizations to individ-
ual parts, as well as more significant 3D trans-
formations that widen the chair into a bench.
But, before you begin making design decisions,
it’s important to develop a program.
DEVELOP A PROGRAM
A program (first introduced in “Define a Project
Program” on page 88) is a list of requirements
or accommodations that a design must
address. It’s rather obvious that a chair’s pri-
mary program is to provide seating. However, a
broader and more detailed understanding of its
anticipated use will steer your decisions about
materials, finishes, and modifications. Making
consistent choices results in a more thought-
fully and thoroughly considered object.
When you begin a project, consider a wider
array of requirements to generate a detailed
program. Start by thinking through where and
how you’ll use your chair. Do you need a single
chair, a bench, a pair of chairs, or a chair with
special details? Think about where it will be
used. Will it go into a formal or casual environ-
ment? Will it get a lot of use? Might it get
moved around? In addition to functional
accommodations, a program should also
include quantitative requirements like a budget
or critical dimensions. If you plan on modifying
your chair into a bench, measure the space
you’re going to put it in, as well as any adjacent
furniture items, like a table.
This well-defined program not only enables you
to produce something that suits its future func-
tion and surroundings, but it also helps you
make smart decisions along the way. Even the
most simple project can overwhelm you with
decisions about what materials to use or how
to customize a design. A program helps you
narrow your choices to support a consistent
end result.
SELECT MATERIALS
Refer to your program to help you evaluate
material options from both a functional and an
aesthetic standpoint. A clear idea of formality,
durability, and budget makes it much easier to
make decisions about material type and qual-
ity, finishing techniques, and fastening meth-
ods. Refer back to “Selecting Materials” on
page 128 if you need a refresher on how to eval-
uate materials. For additional information on
selecting and sourcing materials and fasteners,
consult Appendix B. “Finishes for CNC
Projects” on page 210, which outlines how to
select and apply finishes.
A single 5-30 Minute Chair requires only half of
a 4′ × 8′ sheet of plywood. If you’re cutting one
chair, you’ll have plenty of room for test pieces.
If you are cutting two chairs from a single
sheet, you will need to purchase surplus mate-
rial for test pieces. If you are customizing
dimensions, you’ll need to calculate your mate-
rial quantities, after you finalize your 2D parts’
layout. Most bench sizes will fit on a sheet and
a half of material, leaving room for cutting test
pieces.
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DESIGN FOR CNC
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