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Chapter 3 Screw It or Glue It: Fastening and Joining Parts 67

Epoxies
The classic 5-minute epoxy is a favorite of hobbyists. Epoxy is a glue that comes in two
parts and is activated only when these two parts are combined. This mixing can be
done by hand with a popsicle stick, or more conveniently through an applicator gun
and mixer nozzle.
Epoxy can be used to bond many different types of plastic, metal, and composites. It
dries hard and can be sanded or painted.

You can find epoxy at just about any hardware or home-improvement store (and,
of course, online at McMaster). Look for epoxy putty in the plumbing section of
hardware stores. Propoxy, FastSteel, and QuikSteel are common brands (see Figure
3-11). It’s a putty-based two-part epoxy that hardens like steel after being mushed
together and exposed to air for about 20 minutes.

Plastic Glues and Solvents
Glues made specifically for plastics can be particularly effective because they can react
chemically with the plastic to melt the two pieces into a strong joint. Weld-On is a
well-known brand for bonding acrylic, and is used extensively in the architecture and

FIGURE 3-11 Epoxy putty—the great project saver