Page 88 - Making things move_ DIY mechanisms for inventors, hobbyists, and artists

Chapter 3 Screw It or Glue It: Fastening and Joining Parts 69

One disadvantage is poor vibration tolerance. Hot glue tends to separate from the
base material if much vibration happens, or if anything attempts to pull the two
things apart with much force. Also, try not to glue something that melts when it gets
hot, or you’ll end up with hot goo.

Tape
Common translucent office tape or double-sided tape is not that useful for our
purposes, but the double-sided foam tape you can get at hardware stores can be
handy. You can use this tape to mount components that don’t have mounting holes,
like small motors, or to hold something in place while you drill holes to fasten a
component more securely.

CAUTION Double-sided foam tape is very sticky and hard to remove from
surfaces once attached. Make sure you’ve decided where the components
you are using should be before using it. If you do need to peel off a
connection and redo it, scrape off as much of the tape as you can with a
hobby knife, and use Goo Gone to remove the rest.

Duct tape is easy to tear and relatively strong. Its fancier cousin gaffer tape is similar,
but leaves no sticky residue when removed.

Rivets

A blind or pop rivet consists of a small, flanged metal tube with a metal rod running
through it and a ball at the end (see Figure 3-1). A rivet installation tool pushes the
rivet into a predrilled hole and pulls the rod back into the tube, and the resulting
distortion of the ball flares outward. The rod breaks off in order to form another
flange on the back side of the material. These flanges sandwich two or more pieces of
sheet metal or other thin materials together. You can also find a rivet tool attachment
for a hand drill that works in a similar way. Once installed, a rivet is not removable,
except by drilling it out to create a hole bigger than the initial hole used before
riveting.

Rivets are used primarily when there is access to only one side of the joint, or when
there is no room for a screw-and-nut combination. They are also used for aesthetic
reasons to keep a surface relatively flat looking, and are used in mass production of