Cold Metal Cold Metal ProcessesProcesses

MR. PATTERSONMR. PATTERSON

CONSTRUCTION TECH 1CONSTRUCTION TECH 1

Cold Metal ProcessesCold Metal Processes

1.1. Breaking- bending or forming a flat Breaking- bending or forming a flat shape into a 3 dimensional object.shape into a 3 dimensional object.

a.a. 2 main forms of breaking metal2 main forms of breaking metali.i. Hand breaking-using specially designed Hand breaking-using specially designed

hand tool hand tool

(hand seamer) to bend sheet metal(hand seamer) to bend sheet metal

i.i. Machine BreakingMachine Breakinga.a. Press breakPress break

b.b. Box BreakBox Break

c.c. Pan BreakPan Break

Breaking MachinesBreaking Machines

Example of Flat shape Example of Flat shape formed to a 3D shapeformed to a 3D shape

Fastening Metal Fastening Metal

1.1. DrillingDrilling

2.2. TappingTapping

3.3. RivetingRiveting

4.4. BoltingBolting

DrillingDrilling

1.1. Drilling Drilling ProcedureProcedure

1.1. Layout the center Layout the center of the hole to be of the hole to be drilleddrilled

2.2. Mark the center Mark the center with two with two intersecting linesintersecting lines

3.3. Center punch the Center punch the intersecting linesintersecting lines

DrillingDrilling

1.1. Select the Select the correct drill size correct drill size from a drill indexfrom a drill index

2.2. Put the drill into Put the drill into the drill chuck the drill chuck and tighten with and tighten with the chuck key.the chuck key.

DrillingDrilling

1.1. Clamp material to Clamp material to the tablethe table

2.2. Place a drop of Place a drop of cutting fluid on the cutting fluid on the center punch markcenter punch mark

3.3. Turn on drill and Turn on drill and begin to drill holebegin to drill hole

4.4. Be sure to put even Be sure to put even pressure on the pressure on the drilldrill

Cutting ThreadsCutting Threads

1.1. There are 2 ways There are 2 ways to cut threads:to cut threads:

a.a. External Threads External Threads (bolt)(bolt)

i.i. Die-cutting threads Die-cutting threads on the outside of a on the outside of a piece of rodpiece of rod

b.b. Internal Threads Internal Threads (nut)(nut)

i.i. Tap-cutting threads Tap-cutting threads on the inside of a on the inside of a holehole

Tapping ProcedureTapping Procedure

1.1. Layout hole Layout hole location using location using “Drilling” “Drilling” procedureprocedure

2.2. Select required Select required tap size and tap size and threads per inch threads per inch (TPI)(TPI)

3.3. Consult Tap Drill Consult Tap Drill chart for hole sizechart for hole size

Tap Drill ChartTap Drill Chart

Tap Drill Chart

NATIONAL COARSE THREAD(NC)

 

National Fine Threads (NF) 

Size of Bolt   Size of Threads   Size of   Size of Threads

or Screw and Drill Per   Bolt or Screw Drill Per

Tap to Use Inch   and Tap To Use Inch

                 

1/4"   13/64" 20   1/4"   7/32" 28

5/16"   1/4" 18   5/16"   17/64" 24

3/8"   5/16" 16   3/8"   21/64" 24

7/16"   23/64" 14   7/16"   25/64" 20

1/2"   27/64" 13   1/2"   29/64" 20

9/16"   31/64" 12   9/16"   33/64" 18

5/8"   17/32" 11   5/8"   37/64" 18

3/4"   21/32" 10   3/4"   11/16" 16

7/8"   49/64" 9   7/8"   13/16" 14

1"   7/8" 8   1"   15/16" 14

Threads inside and outThreads inside and out

1.1. 3 classifications 3 classifications of threadsof threads

a.a. National Fine National Fine (UNF)(UNF)

b.b. National Course National Course (UNC)(UNC)

c.c. National Pipe National Pipe Thread (NPT)Thread (NPT)

2.2. Thread DiameterThread Diametera)a) Diameter of the Diameter of the

thread measured thread measured directly over the directly over the threadsthreads

3.3. Thread Pitch- # Thread Pitch- # of threads per of threads per inchinch

Threading ToolsThreading Tools

1.1. TapTap

2.2. Tap handleTap handle

3. Die 4. Die Stock

Threading tools cont.Threading tools cont.

5.5. Cutting FluidCutting Fluid

RivetingRiveting

1.1. Used as a semi-Used as a semi-permanent form permanent form of fasting metal of fasting metal togethertogether

2.2. Can join Can join dissimilar dissimilar materials materials togethertogether

Pop rivetingPop riveting

1.1. Used when back Used when back side of material side of material can not be can not be reachedreached

2.2. Used to connect Used to connect a blind holea blind hole

Pop riveting procedurePop riveting procedure

1.1. Drill hole to Drill hole to correct size for correct size for pop rivetpop rivet

2.2. Slip pop rivet Slip pop rivet into holeinto hole

3.3. Making sure it is Making sure it is pushed in all the pushed in all the way up to the way up to the flangeflange

Pop riveting procedurePop riveting procedure

1.1. Place the pop rivet gun over the pointed Place the pop rivet gun over the pointed end of the rivetend of the rivet

2.2. To seat the rivet squeeze the two handles To seat the rivet squeeze the two handles together until the rivet center pin breaks together until the rivet center pin breaks off.off.