1. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Unit 13 Fastening Metal

2. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Fastening Metals Three ways to fasten metals together –using fasteners (screws, bolts, and rivets) –soldering/brazing –welding Selecting the correct method depends on - the thickness of the metal - strength needed - appearance needed - cost

3. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Drilling Holes in Metal Holes are needed to permit screws to pass through Usually made with high-speed twist drill If threads are needed, hole must be a very specific size

4. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Other Methods Punching: faster than drilling; only on thin metal Threading: cut into the hole with a tap

5. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Metal Fasteners Nuts and bolts Sheet metal screws Rivets

6. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Solder Mixture of tin and lead Used to join thin metal, make electrical connections, and join copper tubing/pipe Most soldering done with 50-50 solder Water supply must be lead-free solder

7. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Soldering Safety When using a propane torch –Wear goggles and insulated gloves –Work area must be free of paper, grease, fuel, and other flammables –Point torch away from you when lighting –Use approved safety procedures and materials –Place sheet metal behind pipes

8. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Important Terms Soldering/brazing: fastening metal by melting a second metal between the pieces Welding: melting metals together High-speed drill: hardened for use in metal Jobbers-length drill: longer length drill Tap: a hardened, brittle, fluted tool used to cut threads into a hole Die: cuts threads onto a rod or bolt

9. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Important Terms (continued) Tap and die set/screw plate: set of tools for making threads Taper, plug, and bottoming taps: tools used to tap threads inside a hole Bolt threads: straight; can be cut the entire length of a rod Pipe fittings: hollow connectors designed to attach to pipe

10. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Important Terms (continued) Teflon tape/pipe joint compound: material used to seal the area between threads when used to deliver gases or liquids Rivet: fastening device held in place by flattening one or both ends Tinning: coating the tip of a soldering copper with solder Flux: material that removes tarnish or corrosion

11. Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Important Terms (continued) Hollow core solder: solder with flux inside Soldering copper: tool used for soldering Sal ammoniac: cube of special flux used to clean soldering coppers Sweating: the process of soldering copper pipe into a fitting