Determine the type of weld (continuous, stitch weld, plug, etc.) for each specific welding operation.

Lesson Plan for

CRT 130-3

NON-STRUCTURAL ANALYSIS AND DAMAGE REPAIR SECTION III

Course HS Title: / Non-Structural Analysis and Damage Repair / Program:
KCTCS Courses included in HS Title: (Lesson is prepared for course highlighted.)
KCTCS Course No. / KCTCS Course Title
Introduction/Context / This lesson will instruct the student on how to determine the type of weld (continuous, stitch weld, plug, etc.) for each specific welding operation. Knowledge of these techniques and the skills required to correct problems associated with this task are necessary for a student to acquire if they wish to compete for high paying, high skilled jobs in a Collision Repair Facility. Entry level technicians need to be able to perform this task to 100% accuracy. Incorrectly performing this task can lead to an automobile accident or create customer satisfaction issues.
Prepared By / School / Date:
Grade Level / No. Students / No.IEP's: / Lesson Length:
Task
Determine the type of weld (continuous, stitch weld, plug, etc.) for each specific welding operation.
No. / Objective
1 / Given the proper tools and instruction, the student will be able to determine the type of weld (continuous, stitch weld, plug, etc.) for each specific welding operation, and pass a written test covering the task with 100% accuracy.

Connections:

New Common Core:
RST 11-12-2
RST 11-12-3
New Common Core Technical
TD-SYS-1
TD-OPS-3
New Science Standards
HS-PS2-3.
Skills Standards:
AA001
EG011

INSTRUCTIONAL MATERIALS/TECHNOLOGY

Teacher Designed Materials and Other Handouts


Textbooks and Workbooks

Author / Title/ISBN No. / Edition / Publisher / Pages

Web Addresses

Title / Publisher / URL
Today's Class / Melior / www.todaysclass.com


Equipment

Quantity / Item / Source


Content/Presentation/Demonstration Outline

Tell students that for MIG spot welding, a special welding nozzle must replace the standard nozzle. Let them know that once in place, and with the spot timing, welding heat, and backburn time set for the given situation, the spot nozzle is held against the weld site and the trigger. Explain that for a very brief period, the timed pulses of wire feed and welding current are activated during which the arc melts through the outer layer and penetrates the inner layer. After this, the automatic shut off goes into action and no matter how long the trigger is squeezed, nothing will happen. Tell them that the trigger must be released and then squeezed again to obtain the next spot pulse. Inform students that because of varying conditions, the quality of a MJG spot weld is difficult to determine. Therefore, MIG plug welding is the preferred method of welding load-bearing members.
Tell students that the MIG lap spot technique is popular for the quick, effective welding of lap joints and flanges on thin-gauge non-structural sheets and skins. Here again the spot timer is set, but this time the spot nozzle is positioned over the edge of the outer sheet at an angle slightly off 90°. Let them know that this will allow contact with both pieces of metal at the same time. The arc melts into the edge and penetrates the lower sheet.
Explain that in MIG stitch welding, the standard nozzle is used, not the spot nozzle. To make a stitch weld, tell students to combine spot welding with a continuous welding technique. They should set the automatic shut-off timer or pulsed interval timer, depending on the machine. The spot weld pulses and shut off occurs with automatic regularity. They would weld then stop, weld then stop, weld then stop as long as the trigger is held in.
Tell them that the arc off period allows the last spot to cool slightly and start to solidify before the next spot is deposited. Let them know that this intermittent technique means less distortion and less melt-through or burn-through. These characteristics make the stitch weld preferable to the continuous weld for working thinner gauge cosmetic panels.


Applications/Practice

1 / Refer to content


Evaluation and feedback Prior to Testing or Lab Work

1 / Objective 1. / Formative assessment / Instructor will observe students as they practice the procedure to assure correct procedure and safety practices are being followed. A checklist will be utilized to chart student progress on the task. Questioning techniques will be utilized as necessary to demonstrate student comprehension / Adaptations and/or accommodations for special needs students will be added if required.


STUDENT ASSESSMENT:(Assess student progress with performance criteria.)

1 / Objective 1 / Summative assessment / written test questions on stated objective / adaptation and / or accommodations for special needs students will be added if required
IMPACT--Reflection/Analysis of Teaching and Learning: (How did students’ progress in relation to the state objectives? Was the instruction successful? Analyze samples of student work particularly that which is unsatisfactory, for the purpose of planning further instruction.)
REFINEMENT--Lesson Extension and Follow-up: (To be filled in as the lesson is modified during initial planning and/or during the teaching learning process.)