Teknologi Dan Rekayasa HAND TOOLS

PLIERS, CLAMPS AND VISES Objectives : After studying this unit, the student should be able to : Identify and describe the various pliers. Identify and describe the types of clamping Select and use the correct toll for the job Teknologi dan Rekayasa

PLIERS Pliers commonly used by workers are the flat nose, the side cutting and the combination pliers. They are used for holding and forming work and for cutting wire. Pliers are made of special steel and drop forged for added strength and resistance to brittleness. Teknologi dan Rekayasa 3

SIDE CUTTING PLIERS Side cutting pliers have flat jaws grooved to hold the work and side jaws sharpened to cut light wire. Teknologi dan Rekayasa 4

FLAT NOSE PLIERS Flat nosed pliers have flat jaws with small grooves. They are used only for holding and forming work. If used carefully, this pliers do not mar the work. Teknologi dan Rekayasa 5

HOW TO CUT WITH PLIERS 1. Mark the line to be cut with a scriber or a piece of soapstone 2. Grasp the piece of wire with the left hand 3. Place the cutting blades of the side cutting pliers at right angles to the wire on the cut mark with the right hand 4. Squeeze the handles of the pliers together with the right hand, completing the cut. Teknologi dan Rekayasa 6

CLAMPING DEVICES Clamping devices used most commonly by workers are the C-clamp, parallel clamp, pipe bar clamp, Vises Grip a nd bench vise. This devices are used to hold and help form the work. Teknologi dan Rekayasa 7

C - CLAMPS C-clamps are available in a variety of sizes and are made of malleable or cast iron. The movable part of the C-clamp is threaded and has a swivel head. The head advances as the screw turns, but does not rotate. This prevents the work from being marred. Swivel head Teknologi dan Rekayasa 8

HOW TO USE C - CLAMPS 1. Clean the work and remove burrs with a file 2. Put a drop of oil in the swivel head occasionally 3. Place the clamps on the work with the swivel head downward 4. Tighten the clamps altenatelly if more than one clamp is being used. Teknologi dan Rekayasa 9

PARALLEL CLAMPS The parallel clamp has two knurled screws. The screw near the work tends to hold the jaws together. The screw on the outside tends to push the jaws apart. The resulting leverage clamps the work when the jaws are parallel. To get result, the jaws must be parallel so that the full surface of the jaws covers the work. If the jaws do not clamp the work evenly, the work will slip. Teknologi dan Rekayasa 10

HOW TO USE PARALLEL CLAMPS 1. Clean the surface to be clamped and remove burrs with a file 2. Open the clamps by turning the screws. Place the clamps so that as much of the jaws are in contact with the work as possible 3. Adjust the clamps until they are open a slight amount 4. Turn the rear screw until the jaws are closed. When the jaws are correctly closed, they rest flat on the work. Teknologi dan Rekayasa 11

VISE GRIP CLAMPS The vise grip wrench is a general purpose wrench used for holding or turning. The vise grip sheet metal clamp is used to hold sheet metal pieces together during fabrication. Vise grip welding clamps are used to hold pieces together while being welded Teknologi dan Rekayasa 12

HOW TO USE A VISE GRIP CLAMP 1. Select the proper type of Vise grip for the job. 2. Adjust the jaw opening to fit the job with the handle closed 3. Open the handles and turn the adjustment screw ¼ turn tighten 4. Place the jaws on job and squeeze the handles into the lock position 5. To open the clamp, press the release lever Teknologi dan Rekayasa 13

THE BENCH VISE The bench vise holds the work between its jaws. The handles turns the clamp screw with moves the outside jaw to clamp the work. On many vises, the immovable jaw is fixed to a swivel base that may be rotated on its axis to secure the work in the proper position if it must be held at an angle to the normal position of the vise. Teknologi dan Rekayasa 14

THE BENCH VISE The vise jaws are hardened and serrated to grip the work rigidly. Work that must not be marred can be protected by using soft removable jaws. The removable jaws are made of soft materials such as brass, copper and leather. These materials do not mar the surfaces, butt the jaws still grip the work securely. Teknologi dan Rekayasa 15

THE BENCH VISE Soft removable jaws Bench vise Teknologi dan Rekayasa 16

HOW TO USE THE BENCH VISE 1. Clean the vise frequently at least daily 2. Place a pair of soft jaws over the jaws of the vise if finished work is being clamped. Put a block below the work to prevent it from slipping down in the vise 3. Tighten the work by rotating the handle. Be careful not to crack thin sections or force circular pieces out of round CAUTION : It is poor practice to tighten the handle of the vise by striking it with a hammer Teknologi dan Rekayasa 17

Teknologi dan Rekayasa