Personal Robotics
• For soldering wires together, make
the wires into two hooks, then twist
the wires together. Follow up with solder
and heat shrink. (Heat shrink is
infinitely preferred, unless you intend
to remove the joint in short order.)
tedious, but larger cuts are a breeze.
Soldering gun: What goes for
the iron goes for the gun. I use my
gun in place of brazing. It is easier,
but the joints are not as strong. It is
also a must if you get into soldering
your own tabbed battery packs or
use heavy gauge wire. (Never solder
non-tabbed batteries.)
Needle Applicator
• Once there is an appropriate
amount of solder, remove the iron
and hold the component still for a few
seconds. Components in a board
should be soldered in such a way that
the solder flows across the whole pad,
through the hole (if plated through),
and across the opposite side.
Needle applicator for
Plastruct Bondene: This allows you
to apply very precise amounts of
adhesive. I like the 20 gauge, 1” long
needle. Remember to keep your
adhesive stored with the thin wire in
the tube to keep it from evaporating.
Larger gauges can handle more viscous
adhesives, like carpenter’s glue.
• Frosty-looking joints are called
“cold.” A proper joint should be clean
and shiny. If you are not getting proper
joints, your temperature may be off.
Machinist’s scribe: This is
useful for marking cut lines on metal
or plastic. You can also scribe multiple
times and bend on the scribe line to
cut many plastics.
Digital Caliper
Tap and Drill Set
Calipers: Calipers allow
you to precisely measure
external and internal
dimensions to a high degree
of precision.
A set of really cheap
digital calipers can be had
for about $20.00 these days,
but, personally, I prefer not to
skimp on measuring tools. I
have had my Mitutoyo digital
calipers for 10 years now and
they were well worth the
investment.
Small through taps: If you
want to tap into brass or other
metals, these are a must. You will
have poor results with small screws
in plastic, however. Taps require a
drill of a certain size to “pave the
way” before you cut threads. Taps
can be bought in sets with the drills.
There are three types of taps:
taper, plug, and bottoming. If you
intend on tapping “blind holes”
where the hole does not go all
the way through the material, then
progress through the three
types, being extra careful with the
bottoming. Otherwise, simply use
the taper all the way through.
To tap a hole, first drill with the
tapping drill, clear the hole of debris,
then screw the tap into the hole,
changing directions frequently to
clear the tap. This is sort of like two
steps forward, one back, as it were.
The harder the material, the deeper
you go; the smaller the tap, the more
critical this is. Also, it is recommended
that you should use tapping fluid on
metals. When tapping blind holes,
clean out the hole frequently.
Keeping the tap perpendicular to
your work is important. If you have a
drill press, you can remove the belt,
chuck up larger taps, and manually
drive the tap, but you must be careful.
You must have a steady hand to do this
with a small tap. You can also make a
tapping guide by drilling a piece of
material with the clearance tap.
Screw
1-72
2-56
4-40
Clearance
#48
#43
#32
Tap
#54
#51
#44
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Bow compass with two
points: This allows you to
make cut-curved sections in
styrene by gently and
repeatedly scribing the cut
you want. Remember to do
the outermost diameters first
on multiple cuts. Smaller
diameter cuts may be
Those of you across the pond
who are accustomed to the highly
complicated, decimal-based metric
system must now screw on your
thinking caps, but I’ll walk you
through this. Take the pitch of your
screw, subtract that from the diameter,
and that is your tap drill size.
86
Bench vise or desk vise: This
JULY 2004