Chapter 12 55 Copyright Goodheart-Willcox Co., Inc. May not be reproduced or posted to a publicly accessible website. Name ________________________________________________________________ Date ________________________ Class ________________ Assigned Job 12-2 Welding a Lap Joint in the Flat Welding Position OBJECTIVE: In this job, you will learn to make an acceptable fillet weld on a lap joint in the flat welding position. Do not attempt this job until: • •• You have read all safety precautions. •• You have satisfactorily completed the Shielded Metal Arc Welding (SMAW) Safety Test. • You have received permission from your instructor. NOTE 1. You will need four pieces of low-carbon steel that measure 1/4″ × 1 1/2″ × 6″ (6 mm × 40 mm × 150 mm). You will also need four E6010 electrodes. 2. Answer the following questions: A. Determine the correct diameter of E6010 electrode to use for welding 1/4″ thick low-carbon steel. Refer to Figure 11-9 in the text. _ ________________________________________________ B. What amperage range is suggested for the E6010 electrode? Refer to Figure 11-9 in the text. _ ________________________________________ amperes C. What polarity is suggested for the E6010 electrode? Refer to Figure 11-6 in the text. _ ________________________________________________ 3. Set the machine amperage for the middle of the suggested amperage range. Also, set the correct polarity. 4. Make a practice weld to set the machine for the best welding results. 5. Arrange two pieces of metal as shown in the following illustration. Tack weld the weldment in three places about 3″ (75 mm) apart. Flip the weldment over and tack weld the other side the same way. 6. After the pieces have been tack welded, arrange the weldment as shown in the following illustration. The weld face must be horizontal when welding in the flat welding position. 1/4 1/4 in. mm 1/4 6