Rosy CupCakes, router safety,
shocked kids, and pirate booms.
MAKE Volume 21 (Desktop Manufacturing) is
brilliant — I’m subscribing. As an engineer in the
mid-90s, I drove usage of tools like SLA, SLS, and
NC machining to create rapid prototypes, and they
quickly showed their benefit in lower cost, better
and faster design iterations, and improved understanding. It’s awesome to see these tools getting to
a broader community — it will allow more creativity,
capability, and fun! —Jeff Zemsky, Glenmont, N. Y.
I found “Instant Paddle” (Volume 21) intriguing
— a new and simple way to construct a paddle.
However, as a woodworker I was shocked at the
unsafe router technique shown. When rounding over
the corners of thin stock, the safe way is to securely
mount the router in a router table with a fence. The
fence guides your stock and also “hides” the majority
of the router bit, keeping your fingers safe. The use of
feather boards would make the procedure even safer.
I built a basic router table (
2007/p.rt) for about $20. Pat Warner’s website
patwarner.com) is dedicated to routing and router
tables; a Google search will produce dozens more.
—Art Mulder, contributing editor, Canadian Home
Workshop magazine, London, Ontario
“The Revolution Will Be Squirted” (Volume 21)
was a bit too rosy about the CupCake CNC. The
article does a good job of pointing out its major
differences from commercial offerings, but not its
shortcomings, such as the quality of the objects
it outputs. The article does state that it uses a
0.3mm filament, but fails to show a close-up shot
to reveal the objects’ coarseness and irregularity.
Another shortcoming is repeatability. Running
a print is hit-or-miss. A part can degenerate halfway
through because the open-loop motion control is
drifting or the filament’s properties have changed.
Hopefully this article will spur many readers to
join the desktop manufacturing revolution. I just
wish it didn’t sound so much like a promotional
piece for MakerBot Industries.
—Charles Erignac, Seattle, Wash.
My student teams in the Destination
ImagiNation program (
idodi.org) have used MAKE’s
ideas to help them succeed. In this video (makezine.
com/go/di), one of my teams uses two “Boom
Sticks” (Volume 13) to make loud cannon booms
during their pirate skit.
—Jeff Harris, Delano, Minn.
EDITOR’S REPLY: Thanks for the clarifications. We could
have shown finer detail, but with its typical 0.37mm
layer thickness, the CupCake isn’t about ultra-precision
— it’s about rapid prototyping, invention, and fun.
MAKE has changed my life and the lives
of my children, and a few hundred kids at their
grade school. I built the electrostatic generator
(“Remaking History,” Volume 21) and presented
it — you should have heard the kids gasp when just
turning a PVC handle with some rabbit fur made
a piece of neon tubing light up. They couldn’t wait
to line up and get shocked by the Leyden jar.
My kids can’t wait for Saturdays when we get
to build. —Ron White, Helena, Mt.
On our “Traditional Cigar Box Guitar” (Volume 21) the
tuners were mounted upside down. Flip them so the
string tension pulls the shaft toward the gear. Thanks
to Bill Ludeman of Palatka, Fla., for spotting our error.
In the breadboard diagram for “Motion-Sensitive
Camera Trap” (Volume 22), the LEDs should be wired
to ground (not power), and the wire from pin 10 should
meet a blue LED’s positive lead (it overshot by one
hole). The corrected diagram is at
cameratrap. Also, 3 standoffs and 6 screws are needed
to mount the Arduino.
In “Puzzle of the Crowned Pulleys” (Volume 22),
Figure C was misinterpreted. In fact the upper edge
of the cylindrical pulley (line b) is not parallel to line
a, and line b is not perpendicular to the incoming
portion of the belt. Thanks to reader Miguel Dimase
of Buenos Aires, Argentina, for catching our slip.
10 Make: Volume