C
D
E
F
Building the Machine
If you’re wondering whether building this machine
is really within your skill range, let me assure you
that if you’re comfortable cutting wood with a table
saw or handheld circular saw, if you can change
and use bits with a drill press or handheld drill, and
if you can use a ruler, you can do this. (If you’re a
master DIYer with tools galore, you won’t have any
trouble building this machine.)
This project is great for shop classes, after-school
programs, and Boy/Girl Scout troops, but it’s also
the perfect parent-child project. I don’t have many
opportunities to work with my dad these days, but
I really enjoyed working with him as we built two (!)
of these CNC machines together. Having someone
else to double-check measurements and hold
pieces as you drill or bolt them down is invaluable,
but it’s also nice to have someone else around to
troubleshoot a problem as well as share the success
when the machine runs for the first time.
Our goal for writing the book was to provide a
good walk-through of the process, with plenty of
pictures, from start to finish. After a handful of
chapters that explain CNC, the basics of joining
MDF pieces, and building the unique parts that give
the CNC machine the ability to move smoothly,
you’ll get straight to the electronics and building the
CNC machine frame.
Your first task will be to cut, drill, and assemble
the machine’s tabletop that also serves as the x-axis
(Figure G). Completing the tabletop will not only
give you a place to attach the remaining components of the machine, but you’ll also become quickly
familiar with the handful of standard tasks required
for the rest of the project (counterboring, using
cross dowels to connect parts, cutting lead screws,
and so on).
As you build your machine, you’ll cut and drill
some special pieces called bearing and rail
assemblies, or BRAs (Figure H). These allow your
CNC machine to move smoothly and accurately
on all three axes by riding on another piece of
angled aluminum rail. Patrick’s method for building
and using the BRAs is extremely simple as well
as reliable.
Building chapters are short, so you’ll always have
a good starting and stopping point. You’ll begin with
the x-axis, add on the parts needed for the y-axis
(Figure I) and finish up with the z-axis (Figure J).
While building the CNC machine frame, you’ll also
be given instructions for wiring up all the electronics.
We tell you exactly what motors, drivers, and power
62 Make: Volume 21
