SeaPerch ROV Build v.2011-01AK Student Manual
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tabletops!). If using a drill press, make sure that the object is held firmly and fingers are not
near the drill bit.
Safety While Soldering (refer to Appendix II –How to Solder Like a Pro for tips)
Soldering Uses High Heat: All soldering involves a very hot soldering iron as well as
temporarily-hot electrical connections which take a few moments to cool after soldering. Do not
touch the tip area of a soldering iron, even when it appears to be off or unplugged, as it does
not look different when it is hot compared to when it is cold and it can remain hot for 10 minutes
or more after use. Connections should be allowed to cool after soldering before they are moved
or touched. As noted earlier, always wear eye protection, even when just in the same area as
someone who is soldering.
Keep the Soldering Iron in Its Holder When Not in Use: Great care should be taken to
place the soldering iron back into its holder whenever it is not in use for soldering. Never just
set it down on a tabletop, where it could burn anything it touches.
Safety While Potting Motors for Thrusters
SeaPerch ROV thrusters are assembled by potting small electric motors in wax. The following safety
issues should be reviewed with everyone involved in the potting process:
Melting Wax: The standard SeaPerch wax-melting approach is to warm “toilet bowl ring” wax
in a heated pot or a metal container placed in a hot water bath, usually employing an electric
hotplate to heat the water (and wax). It is important to always monitor the temperature of the
wax or use a water bath (and NOT let all of the water evaporate - keep adding water to
maintain it at about ½” to 1” deep). Otherwise, the wax can get EXTREMELY hot, even hot
enough to melt the plastic thruster housings. Fortunately, bowl ring wax has a relatively low
melting temperature, but it must still be heated to about 150 degrees Fahrenheit (F) for proper
pouring. Although its flash point is over 500 degrees F, manufacturers usually recommend not
exceeding 200 degrees F, so you should try to keep the wax at about 180 degrees F or below
(using a thermometer is best, as temperature control knob markings may be inaccurate). If the
wax is allowed to get too hot, skin burns are possible. In case of a burn, quickly rinse the area
with plenty of cold water and seek medical attention. Care should be taken to prevent getting
the hot wax onto skin or clothing. Wearing a protective smock or apron and gloves is
recommended. Pour the wax slowly and carefully to prevent spills and potential burns.
During the final step of thruster potting when the lid is placed onto the thruster housing, melted
wax can squirt out of the small hole in the lid where the wires pass through. If the lid is pressed
quickly into place, wax can even squirt as high as the ceiling or onto nearby walls and people.
Placing a paper towel over the lid and pressing slowly is recommended to avoid the wax-
squirting problem. Protect nearby walls and floor areas with paper or tarps. Obviously,
everyone in the area should be wearing eye protection.
Safety with Electricity and Batteries
The low-voltage (12 volts, direct current (DC)) battery power source used with SeaPerch ROVs is
relatively safe and well-proven in students’ hands. However, they should be cautioned about potential
problems from short-circuits as well as electrical safety issues in general.
Battery Short-Circuit Hazard: Although the battery can be used quite safely when it is
connected properly to the ROV, it can be damaged, cause wires to melt, or even start a fire if
its positive and negative terminals are connected directly together. That is called a “short
