On the table

1
On the table

• Safety agreement
• Electrode tables (page 134 and 135)
• Look over and complete s 3 4 on
• page 25 in handbook

2
Sheet Metal
3
Classification

• Sheet metal metal that is less than ¼ thick
• Anything thicker is considered plate metal

4
Uses for sheet metal

• Street signs
• Tool parts
• Toys
• Appliances (washers, dryers, refrigerators,
  ranges, etc)
• Mailboxes
• Desks, filing cabinets, and other office devices
• Heating Ventilation and Air Conditioning (HVAC)
• Exhaust hoods
• Metal roofs
• Commercial building studs and roofs
• Transportation (automobiles, boats, trailers,
  aircraft, space vehicles, etc.)

5
Types of Sheet Metal

• Steel
• Galvanized steel (coated with zinc to resist
  corrosion and rusting)
• Tinplated steel
• Stainless steel
• Aluminum
• Copper
• Brass

6
Hem and Seam Allowances

• Hem a fold along an edge that does away with
  the sharp edge
• Strengthens resulting edge

7
Hem and Seam Allowances

• Seam joint made by fastening 2 edges together

8
Allowance

• Amount of metal required to make a hem or seam
• Depends on
• Thickness of the metal
• Size of the object
• Fastening method
• Rivets and spots welded seams are wider than
  soldered seams

9
Sheet Metal Sizes (also wire sizes)

• Thickness specified in
• Gage number
• Actual thickness
• Sheet metal gage
• Slots that correspond to different sizes

10
Layout

• Pattern
• Full size drawing of shape
• Blue print
• Plan of measurements, cuts, and details for a
  project
• Scratch awl
• Sharp tool used to layout lines on sheet metal
• A marker also works!

11
Sheet Metal Tools

• Tin Snips
• Max thickness that should be cut 20 gage
• Nibbler
• Electric sheet metal shear
• Manual Cornice Brake
• Has adjustable teeth and can fold or bend metal
  any distance from the edge
• Manual operated shear
• Foot operated blade that can cut up to 20 gage
  steel

12
Sheet Metal Tools
Manual Cornice Brake

• Manual operated shear

Tin Snips
Nibbler
13
Patterns and Plans

• All sheet metal projects start from blue prints
• Sheet Metal Project - Page 41
• Go through it with paper first!
• Materials
• Scissors
• Pencil
• 11x17 sheet of paper
• Scale

14
Sheet Metal Box Plan
15
In lab today

• Demonstration on
• Metal shear
• Cornice brake
• Layout tools (square, scribe, etc.)
• Tin snips
• Work on
• SMAW people must work on SMAW
• Anyone who is not assigned a SMAW booth
• 5 bits on Drill Doctor OR
• Sheet metal project
• Next time
• Sheet metal quiz
• Lathe introduction
• Introduction to screwdriver project