48 December 2016
PRACTICAL 3D PRINTING n BY CHUCK HELLEBUYCK
The design was created from
scratch using Tinkercad 3D design
software. It’s so simple to use since
it was originally designed for kids,
but still has many features that make
it powerful enough for creating
3D printed prototypes. For the
electronics, I decided to design my
own circuit board and router it out on
my X-Carve CNC.
Electronics
The first step was to get the
circuit to work. I did this on a
breadboard. I found a simple dual
LED flasher circuit also known as
an astable multivibrator (Figure
2) that I found at f-alpha.net, so
no microcontroller was needed or
involved. I guess you could call it old
school electronics.
The cost of the parts would be
less than $1 but since I had most
of them in my component drawers
(some of which are 3D printed), I
was able to build a prototype rather
quickly.
From there, I created a board
layout in ExpressPCB since I know
that software so well. Rather than
spend money on a single prototype,
I decided to use my CNC to produce
the board. I imported the final design
into Copper Connection board layout
software (that I’m still learning).
Copper Connection can
produce Gerber files from
any ExpressPCB file, so I
imported the ExpressPCB
file, exported the Gerber
files, and then imported
those into Flatcam software.
Flatcam is free software
that can create the G-Code
for my CNC. Flatcam will
produce a G-Code file for
routing out the traces and
also the drill file for creating
the holes. I used my X-Carve
CNC to do the dirty work on a single-sided bare copper board (Figure 3).
With a little bit of soldering, the
flashing LED board was ready to use
(Figure 4). It runs directly off a nine
volt battery so no regulator is required
(again, no micro makes this easier).
The 3D print design could now be
created because I had my final board
size and component placement.
I needed two holes in the box for
the red LEDs to poke through. I also
wanted an on/off toggle switch so a
hole on the top of the box was called
for, plus I needed a nine volt battery
holder of some kind.
hen I record my You Tube videos, I need to be left alone without interruptions. I do
most of my filming in my garage workshop and this can sometimes be a problem.
Occasionally, one of my family members will enter the garage and oftentimes
mess up a film clip. It’s unintentional, but I wanted a way to let them know I was filming. I
tried a sign on the door but that didn’t always catch their
eye. So, I decided to design and 3D print a portable sign that
has flashing LEDs to bring attention to the fact I’m filming,
so don’t enter. The finished design is shown in Figure 1.
hen I record my You Tube videos, I need to be left alone without interruptions. I do
most of my filming in my garage workshop and this can sometimes be a problem.
Occasionally, one of my family members will enter the garage and oftentimes W
3D Printed On-Air Flashing Sign
Using 3D printers for practical
projects on your workbench.
n FIGURE 2. LED flasher.
n FIGURE 3. CNC’ing the circuit board.
n FIGURE 1. On Air sign.
