SHAPER A Shaper is a machine tool used for shaping or surfacing metal and other materials. The...

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SHAPER A Shaper is a

machine tool used for shaping or surfacing metal and other materials. The cutting tool on the shaper oscillates, cutting on the forward stroke, with the work piece feeding automatically toward the tool.



TYPES OF SHAPER• ACCORDING TO THE TYPE OF MECHANISM USED

FOR GIVING RECIPROCATING MOTION TO THE RAM:

1. Crank Type.2. Geared Type.3. Hydraulic type.

• ACCORDING TO THE POSITION AND TRAVEL OF RAM:

1. Horizontal Type.2. Vertical Type.3. Travel Head Type.



CONTINUED…• ACCORDING TO TYPE OF DESIGN OF THE TABLE:1. Standard Shaper.2. Universal Shaper.

• ACCORDING TO TYPE OF CUTTING STROKE:1. Push Type.2. Draw Type.

1. According to position and travel of ram

a) Vertical type of shaper-The ram holding the tool reciprocates in a vertical Vertical plane.it is also possible to swivel the ram about the vertical in vertical plane on either side of vertical axis .The work table of a vertical shaper can be given an extra rotary movement in addition to the other movements of a standard shaper table.

b) Horizontal type of shaper-Here the ram reciprocates in a horizontal plane.

c) Traveling head type-ram carrying the tool moves crosswise as it reciprocates to give the required feed .Used for heavy workpieces so that workpiece is stationary.

2. According to type of design of the table

• Standard Shaper-The table has only two movements (plain) vertical and horizontal.

• Universal Type-In universal shaper in addition to the two movements provided on the table of standard shaper ,the table can be swivelled about an axis parallel to the ram ways and the upper portion of the table can be tilted about a second horizontal axis perpendicular to the first axis.

3. According to the type of cutting stroke

• Push type- This is the most general type of shaper used in common practice. The metal is removed when the ram moves away from column.

• Draw type- The metal is removed when the ram moves towards the column of the machine.



SHAPING MACHINE

• A shaping machine is used to machine surfaces. It can cut curves, angles and many other shapes. It is a popular machine in a workshop because its movement is very simple although it can produce a variety of work.

• Shaping machines come in a range of sizes but the most common size is seen opposite.



PARTS OF SHAPING MACHINE• Base - The support where all parts are mounted.• Column - It's a housing for the operating mechanism

and principal support for all other component parts.• Table - Is fixed to an apron or saddle moving on rails

feeding or giving cross motion to the work. The cross rails are mounted on another saddle which moves up and down on ways on the column face to allow positioning of the work to the tool.

• Toolhead - Holds the tool and in some applications positions it. The toolhead has a tool slide and feed screw for adjusting the tool for depth of cut without changing the table height. Some shapers provide an automatic feed for the tool consisting of a roller attached to the head engaging a feed bar mounted along the ram ways.



CONTINUED…

• Ram -The ram is the reciprocating member of the shaper. It slides on the accurately machined dovetail guideways on the top of the columns and is connected to the reciprocating mechanism.

• Crossrail -It is mounted on the front guideways of the column.It has two parallel guideways on its top in the vertical plane.

• Saddle -It is mounted on the crossrail which holds the table firmly on its top. Crosswise movement of the saddle by rotating the cross feed screw causes the table to move sideways.



SHAPER MECHANISMS

• The main parts are indicated below:

• The tool feed handle can be turned to slowly feed the cutting tool into the material as the 'ram' moves forwards and backwards. The strong machine vice holds the material securely. A small vice would not be suitable as the work could quite easily be pulled out of position and be damaged. The vice rests on a steel table which can be adjusted so that it ca be moved up and down and then locked in position. Pulling back on the clutch handle starts the 'ram' moving forwards and backwards.

A KINEMATIC DIAGRAM OF A SHAPING MACHINE



CRANK SHAPERS• Crank Shapers generally use a bull gear which has

an offset pin which can be adjusted to vary the radius of the throw and therefore alter the stroke.

• This pin, mounted in a sliding block which can reciprocate in a slot in a pivoted lever, induces a slow and fast cycle to the oscillation of the lever.

• As the free end of the lever is linked to the shaper ram, the slow motion is used for the cutting stroke and the fast motion to return the ram on the non-cutting stroke.

• In most shapers, the ram is slotted to receive a fastening stud to secure the link connected to the lever. The slot enables the ram to be positioned by adjustment to the work piece.



RACK OR GEARED SHAPERS

• Rack or Geared Shapers can have either one or two racks on the underside of the ram, Two belts, one crossed, driving to idling pulleys either side of a pulley fixed to the rack pinion driving shaft. Adjustable dogs on the ram, engage the belt shifting linkage to move the forward belt onto the fixed pulley for the cutting stroke, replacing it with the reverse belt for the rearward stroke.

• The shifting belt system did not allow for accuracy in length of cut so was not a popualr choice for those wishing to cut to a line.



HYDRAULIC SHAPERS• Hydraulic Drive Shapers

utilise a hydraulic ram to reciprocate the ram, the inherent bias of a double acting ram imparting a natural quick return stroke.

• Adjustable dogs determine both the length of stroke and the position of the ram.

• Simplicity of control over speed, stroke etc together with constant cutting speeds, had to be weighed against cost, the hydraulic shaper was the most expensive of all.

• Nice to work, though.

SHAPING HORIZONTAL AND VERICAL SURFACES

SHAPING INCLINED SURFACES

The tool post and the tool slide can be angled as seen below. This allows the

shaper to be used for different types of

work • DIA A: The tool

post has been turned at an angle so that side of the material can be machined

• DIA B: The tool post is not angled so that the tool can be used to level a surface.

• DIA C: The top slide is slowly feed into the material so that a ‘rack’ can be machined for a rack and pinion gear system.

GROOVING AND STRAIGHT TOOTH CUTTING FOR SPUR GEARS



USES OF SHAPERS• Keyways in the boss of a pulley or gear can

be machined without resorting to a dedicated broaching setup.

• The most common use is to machine straight, flat surfaces but with ingenuity and some accessories a wide range of work can be done.

Other examples of its use are:• Dovetail slides.• Internal splines.• Keyway cutting in blind holes.

A photographic view of a shaping machine

A shaping machine in action



SLOTTER



WHAT IS SLOTTER???• The Slotting Machine falls under the category

of reciprocating type of machine tool, the ram holding tool reciprocates in a vertical axis.

• Slotter is used for cutting grooves, keyways and slots of various shapes, for making regular and irregular surfaces both internal and external, for handling large and small workpieces, for cutting internal or external gears.



TYPES OF SLOTTING MACHINES

1. Puncher Slotter: It is a heavy, rigid machines designed for removal of large amount of metal from large forging and castings. Feed is controlled by electrical gears.

2. Precision Slotter: It is a lighter machine and operated at high speeds. It is designed to take light cuts giving accurate finish. They are usually fitted with Whitworth Quick Return Mechanism.



SLOTTING MACHINE PARTS

• Base: Rigidly built to take up all the cutting forces and entire load of the machine.

• Column: It is a vertical member which is a cast integral with the base and houses driving mechanisms of the ram and feeding mechanisms.

• Saddle: It is mounted upon the guideways and may be moved toward or away from the column either by power or manual control to supply longitudinal feed to the work.



PARTS CONTINUED….• Cross-slide: It is mounted upon the guideways of

the saddle and may be moved parallel to the face of the column.

• Rotary Table: Circular table mounted on the top of the cross-slide.

• Ram and Toolhead Assembly: It is a reciprocating member of the machine mounted on the guideways of the column.

KINEMATIC DIAGRAM OF A SLOTTING MACHINE



SLOTTER OPERATIONS

• Machining Flat Surfaces.

• Machining Cylindrical Surfaces.

• Machining Irregular surfaces and Cam machining.

• Machining Slots, Keyways and Grooves.

A photographic view of a slotter

A slotting machine in action

SHAPER A Shaper is a machine tool used for shaping or surfacing metal and other materials. The...

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