Copyright Goodheart-Willcox Co., Inc. 261 6. Which of the following welding techniques is not used for FCAW? A. DCEN B. Forehand or push angle welding C. Perpendicular welding D. Backhand or drag angle welding 7. Which of the following does the welder actually observe and control to obtain a good- quality weld bead? A. Nozzle-to-work distance B. Electrode extension C. Contact tube–to-work distance D. Arc length 8. What does increasing the voltage do? A. Increases penetration B. Increases deposition C. Increases pool width D. Preheats the electrode more 9. What does increasing the contact tube-to-work distance do? A. Increases penetration B. Increases deposition C. Increases pool width D. Preheats the electrode more 10. The electrode should extend _____ beyond the end of the contact tube for spray transfer with GMAW. A. 1/4″–1/2″ (6 mm–13 mm) B. 1/2″–1″ (13 mm–25 mm) C. 3/4″–1 1/2″ (19 mm–38 mm) D. 3/4″–3 3/4″ (19 mm–95 mm) 11. List two advantages of backhand welding over forehand welding. 12. _____ transfer deposits more metal for a given size electrode wire. A. Short circuiting B. Globular C. Spray D. Pulsed-spray 13. List two ways to reduce spatter. 14. The weld pool shape for a fi llet weld is a(n) _____ shape. 15. The opening at the root pass of a butt weld is a(n) _____ shape. STEM Connections 1. Engineering. Conduct research to fi nd out more about wire feeders commonly used to feed aluminum electrodes. Examine one or more wire feeder models, if possible. Then brainstorm ways to improve the equipment to help reduce the number of bird’s nests that occur when soft wire is fed through the wire feeder. Write a proposal for the improvement you think would be most likely to succeed. 2. Science. Conduct research to fi nd out more about aluminum oxide. Write a short report describing the differences in the chemical and mechanical properties of aluminum and aluminum oxide. Identify your sources. 3. Technology. Conduct research to fi nd out what types of materials are used for backings for various types of metals. Create a table showing several base metals and the backing material used for each, as well as whether the backing becomes part of the completed joint. Curricular Connections 1. Critical Thinking. Consider the GMAW and FCAW welding processes. Which process, in your opinion, requires more thorough cleaning between passes on a multiple-pass weld? Write a paragraph explaining your answer. 2. Language Arts. Write an essay comparing and contrasting the forehand and backhand welding methods. Identify the advantages and disadvantages of each method. 3. Social Science. Experiment with different positions for holding the welding gun. Remember that the grip you choose should be comfortable so that you can hold the gun for long periods of time without fatigue. Try at least three different positions. Write a report detailing your fi ndings.