What Is Slotter Machine?
A slotter machine is a reciprocating machine in which the rams and cuttings that hold the tool in the vertical direction are processed only in the downstroke & not in the downward strokes.
These machines are similar to a shaper or planer machine. The working principle of the slotter machine is similar to that of the shaper machine.
The only difference between the shaper machine and the slotter machine is that the RAM of the shaper machine operates in the horizontal direction, and the ram of the slotter machine operates in the vertical direction.
Vertical shaper machines and slotter machines are almost the same if the manufacture, operation, and use are related.
Parts of Slotter Machine:
A slotter machine consists of the following parts:-
- Base or Bed.
- Guide Ways.
- Cutting Tool.
- Cross Slide.
- Rotary Table.
#1. Base or Bed-
As the name suggests, this is the basics of the slotter machine. All other parts of the machines exist on this basis. The base is made of cast irons which can carry compressive loads by various parts of the machine.
Cast iron is a very strong and hardened material. The shock-absorbing capacity of cast iron is also high.
The pillar is located just above the base and is made of cast iron. It is connected in shapes like a base and box.
This pillar is the housing for various driving mechanism components such as gear arrangement, pulleys, etc., that cause the reciprocating action of the ram.
This column also serves as a support for RAM and the workforce. Directions are made at the top of the column, on which Ram can slide.
#3. Guide Ways-
On the front of the column, there are directions. It is also known as vertical directions because it is oriented in a vertical direction at the face of the pillar.
The main functions of the ram are to move up and down to get power from the machine’s driving mechanism inside the pillar.
#5. Cutting Tool-
These are the parts of the slotter machine that cuts off the unwanted part of the workpiece. The single-point cutting tool is used as a cutting tool in a slot machine. I made this with high-speed steel.
The cart is located above the base, which lifts all the parts under and above the table. It performs a saddle, cross-slide, rotary table, and workpiece.
The saddle is placed on the directions and can move toward or away from the column. It can be carried by power or manual control to supply longitudinal feed to work.
The top face of the saddle is properly finished to provide directions for the cross-slide. Guidelines on the saddle are pending guidelines on the base.
#8. Cross Slide-
The cross-slide is mounted on the faces of the column and can run parallel to the face of the column, i.e., forward or backward. This can proceed manually or by supplying power to achieve cross-feed.
#9. Rotary Table-
The rotary table is a circular table that is placed above the cross-slide. This tables can be rotated, so it is known as a rotary table. It can be rotated by rotating a worm which is attached to a worm gear on the underside of the table.
It is this rotary table, T-slots cut on the top face of the table, to fit various clamping devices to hold the workpiece. This table enables a spherical or contour surface to be generated on the workpiece.
In some slotter machines, tables are graduated in degrees so that the table can be rotated equally to any part for indexing or diving the perimeter of the workpiece.
Types of Slotter Machine:
There are mainly four types of slotter machines: –
- Puncher Slotter.
- Precision Tool Room Slotter.
- General Production Slotter.
- Keyseater Slotter.
#1. Puncher Slotter-
The puncture slotter is a very heavy machine and is operated with a powerful motor. This scooter is used to remove large quantities of metals from large quantities of forgings or castings.
The length of the stroke of the puncture slotter is also large, from about 1800 to 2000 mm. The puncture slotter ram is usually operated by a spiral pinion mesh with severed teeth on the underside of the ram. In this Sloter, feed is also cut by electric gear.
#2. Precision Tool Room Slotter-
The Precision Tool Room Slotter is a lighter machine and is operated at higher speeds. This slotter is designed for very precise machining.
This machine is designed to take very lights cuts & give a very precise finishing. As these machines use special jigs, they can handle many tasks on a production basis.
This machine is also goods for general purpose work. This machine typically uses the Whitworth Quick Return mechanism for Ram’s action.
#3. General Production Slotter-
Production slotter is mainly used for generals production work. Slotted discs with connecting rods are used for the reciprocating action of the RAM. The flywheel is used in this slotter to stop the stroke at the end of the stroke.
#4. Keyseater Slotter-
Keyster slotter is also identified as a keying machine which is a specific type of slotter designed to cut keyways. The keytar is similar to vertical shapers, the difference being that the cutting tool on a critical sitter enters the workpiece as a bottom, and cuts are down-stroke because the tool on a shaper enters the workpiece as the top and Cut downwards.
Drive Mechanism of Slotting Machine:
In the slotting machines, the metal is cut during the upward stroke, and no metal is removed during the downward stroke. So, the time taken in downwards stroke can be reduced to improve the working speed of the machine.
So, a quick return mechanism is used to drive the ram of the slotting machine.
A quick return mechanism is an apparatus to produce a reciprocating motion in which the time taken in return stroke is less than the time taken in the forward stroke.
There are three types of quick return mechanism which can be used in slotter machine:-
- Hydraulic drive.
- Crank and slotted link mechanism.
- With worth mechanism.
Slotter Machine Operations:
There are mainly four types of operations performed using the slotter machine: –
- Flat Surface Machining.
- Irregular Surface Machining.
- Cylindrical Surface Machining.
- Machining Slots, Keyways, and Grooves.
#1. Flat Surface Machining-
Flat surfaces can be easily generated internally as well as externally using a slot machine. First, mechanizing the workpiece is supported on parallel strips so that the tool has clearance with the table when it is in the extreme downward position of the stroke.
The work is then properly applied to the table, and the position and length of the table are adjusted.
A clearance of approximately 20 to 25 mm is provided prior to the start of the cutting stroke to allow for feed movement during the idle stroke.
The table is pressed properly to prevent any longitudinal or rotary movement. The work is performed using a rough and a finishing tool. If the inner surface is to be mechanized, a hole is drilled into the workpiece, through which the slotter tool can pass at the time of the first cutting stroke.
If a second surface is to be machined parallel to the first machined surface, this can be done by simply rotating the table through 180 ° without changing the setting.
If the surface is to be mechanized perpendicular to the first surface, this can be done by rotating the table by 90 degrees and adjusting the saddle and cross-slide.
#2. Irregular Surface Machining-
For machining irregular surfaces, the workpiece is fastened to the table, and necessary adjustments of equipment and machine are made.
The irregular surface can be mechanized by combining various feed movements such as cross, longitudinal, and rotary feed movements. Any contour surface can be mechanized using these three feed movements.
#3. Cylindrical Surface Machining-
Sloter machines can easily be used on machining cylindrical surfaces. It can be used for an internal machine as well as the outer surface of a cylinder.
The instrument is set radially at work, and the necessary adjustments of the instrument, saddle, table, cross-slide are made. The saddle is stuffy in its position.
After all adjustments, the machine is started, and a machining feed is provided using a rotary feed screw, which rotates the table through a small arc after each cutting stroke.
#4. Machining Slots, Keyways, and Grooves-
Special types of slotter are used as the main seater slotter for machining slots, keyways, and grooves, which we discussed earlier. Interior, as well as outer grooves, are very easily cut using this machine.
A slot is specially designed to cut internal grooves, which are very difficult to produce in any other machine. A slotter is specially designed to cut internal grooves that are very difficult to produce in any other machine.
The gear teeth can be made into a slot by cutting grooves externally as well as at the circumference of the work. The circumference of the workpiece is divided by the graduation of the rotary table.
Specification of Slotter Machine:
The size of the slotter machines can be specified by the following specifications:-
- Maximum strokes length ram.
- The diameter of the table.
- Amount of cross & longitudinal travel of the table.
- A number of speeds available.
- A number of feeds available.
- Motor horsepower.
- Type of quick return mechanism.
- Floor space required.
- Net weight of the machine.
Application of Slotter Machine:
The slotter machine has the following applications:
- It is used to cut keys,
- Grooves and slots of various shapes,
- To create regular and irregular surfaces, both external and internal,
- Internal and external gear cutting,
- For big, odd jobs.
Advantages of Slotter Machine:
The advantages of the slotter machine are:
- A slotter machine is a light machine that is comparable to other machine tools.
- The price of a machine is not so high.
- Less maintenance is required.
- The machine produces a fine surface finish for a workpiece.
Disadvantages of Slotter Machine:
Disadvantages of slotter machines are:
- Rigid in construction.
- The skilled worker has to work.