Page 180 - Robot Builder's Bonanza

RAPID CONSTRUCTION WITH SEMIPERMANENT FASTENERS 149

Figure 14-4 Plastic cable ties and
mounts can be used to secure pieces
to your robot. Use several ties for
larger components. The mounts may
be stuck onto the robot with self-
adhesive tape or mounted using small
fasteners.

PLASTIC TIES
Intended to hold bundles of wire and other loose items, plastic ties can also be used to hold
things to your robot. The tie is composed of a ratcheted strip and a locking mechanism. Loop
the strip into the mechanism, and pull the strip through. The locking mechanism is one- way:
you can tighten the strip, but you can’t loosen it (this applies to most plastic ties; some have
a releasable lock).
Plastic ties are made of nylon and are very strong and durable. They’re available in a variety
of lengths, starting at 100mm (a little under 4″) to well over 12″. Anchor the tie into a hole
you’ve drilled in your robot, or use one of several mounts specifically designed for use with
plastic ties (see Figure 14-4). I prefer mounts designed for use with hardware fasteners; they
provide a stronger hold.

STICKY TAPE
Sticky tape is a broad family of products that have an adhesive on one or both sides of the
tape. Sticky tape is cheap, easy to use, and bonds nearly instantly to the surfaces you apply it
to. While sticky tape makes for handy construction material, remember that the tape adhesive
is gummy and can leave residue on the parts. Use denatured alcohol to remove the residue.
(But test first to ensure that the alcohol doesn’t dissolve the parts of your robot you want to
keep!)

Most sticky tapes are not dimensionally stable; that is, under stress and load— like a drive
G motor— parts may shift under the adhesive. This can cause a “creep” that will result in parts
becoming misaligned over time. Use sticky tape for noncritical applications only, or when you
provide another way (such as mechanical stops) to keep things aligned.

DOUBLE- SIDED FOAM TAPE
A common staple in any robot builder’s workshop is a roll of double- sided foam tape. This
is like the aforementioned sticky tape, but thicker. This tape is composed of a layer of springy

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