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Hey Guys my name is Krishnendu Mukherjee. I am from West Bengal, India. I am also a student of Bachelor of Technology in Mechanical Engineering, On this website, I mainly look at the mechanical department. There are also many more students and teachers who cover other subjects. And I am love to create and share study-related materials on the Internet. Krishnendu always tries to provide you with the best and most accurate information.
Marking Out Tools in Workshop
- Definition of marking tools
This is what we mean by using marking tools in a workshop. When we do any work in the workshop or do any cutting or machining in the workpiece. we have obtained accurate sizes and shapes on a job or workpiece using many types of Marking tools.
There are many types of Marking Tools
Here is the list of types of marking tools in the workshop
- Scriber
- Engineer’s Square
- Spring Dividers
- Punch
- Prick Punch
- Center Punch
- Surface Gauge
- Surface Plate
- Marking Table
- Angle Plate
- Vee Block
- Parallels
- Bevel Square
- Combination Set
Scriber
Now Let’s talk about Scriber in this moment
Scriber, This tool is a hard and sharp tool made of steel that is used to cut a metal or any metal in a certain direction and in the right size.
It Include with a Conical Point (top angle usually 159°) and a Knurled Body.
Instructions to work with Scriber (Marking Tools)
When working with scriber you should always work carefully. And should be moved with appropriate pressure along the gills of the steel rule as it always marks a specific spot or line. So if you do not do this carefully, your workpiece may be damaged or endangered.
The scriber is the most important mark out tool in a mechanical workshop or fitting shop.
Engineer’s Square
Engineer’s square (figure 14) is made of hardened tool steel. It is used for checking the straightness and the squareness of a workpiece. It can also be used for marking perpendicular lines onto a workpiece.
Engineer’s square is made up of two parts, one is a steel blade and the other is a stock body that looks like a square, it is a thick part which is attached to the L shape.
These tools are very strong and are made of stainless steel. As a result, these tools are harder and stronger. Which we can use as a handheld tool at very simple.
The stock has standard sizes such as 50-1000mm.
To take and mark quantities using an engineering scribe. The difference between a tri square and an engineering square is the accuracy and the material used.
Spring Dividers of a Marking tool
The Spring Dividers tool is also a marking out tool or marking tool. Which we use to draw a circle or write something on a workpiece in an engineering workshop
Structure of Dividers or features of Spring Dividers marking tool
Spring dividers have two legs, and to make it look like a campus, one foot is fixed on the workpiece and the upper leg is rotated, creating a circle on the workpiece.
Uses of Dividers marking out tool or marking tool.
- We use the Spring Dividers or Dividers marking tool to measure the distance between two points.
- Before we draw a line with the steel rule we use to take a certain direction or quantity.
The result is that when we take a measure with a steel rule and divide it into two points with dividers, we get the exact size and the exact point. - We use the Dividers marking tool to mark circles and arcs on metalwork
Punch
Punch tools have different uses in different fields. If you are not familiar with the punch tool, let’s go introduce you to the Punch tool marking tool
It is a marking tool that helps us in our field of work.
It is usually shaped like a rod. Its made of steel, the front part of which starts at the body. Its structure varies from field to field.
There are two types of punch namely the Centre Punch and the Dot Punch. A dot punch has a point angle of 60¢X and it is used for making small dots on the reference line. The center punch has a point angle of 90¢X as shown in figure 16 and it is used for making a large indent on a workpiece for drilling. Both punches are made of hardened tool steel.
Along with this, two more marking tools were named Prick Punch and Center Punch
→What is the function of prick punch or Marking Punch Tools
A prick punch is similar to a center punch but used for marking out. It has a sharper angled tip to produce a narrower and deeper indentation. The indentation can then be enlarged with a center punch for drilling.
A prick punch is a layout marking tool or marking out a tool that is made of steel, approximately 100 mm to 150 mm.
→What is the function of Center Punch or Marking Punch Tools
A center punch is used to mark the center of a point. It is usually used to mark the center of a hole when drilling holes. A drill has the tendency to “wander” if it does not start in a recess. A center punch forms a large enough dimple to “guide” the tip of the drill
It is like a prick punch but its point is ground at an angle of about 90 °.
Surface Gauge
The surface gauge is a marking tool or marking out tool that we use on the surface plate that helps to draw the layout or line of the work. It is commonly used in mechanical workshops.
Type of Surface Gauge Marking Tool
There are usually two types of surface gauges.
- Fixed Type Surface Gauge
- Universal Surface Gauge
⇒Fixed Type of Surface Gauge
The way it is made consists of a heavy flat base and a spindle, fixed upright, to which a scriber is attached with a snug and a clamp nut.
⇒Universal Surface Gauge
The Universal Surface Gauge is one of the most common marking tools used for
This surface gauge has the following additional features.
- Can set the spindle in any position
- Fine adjustments can be made quickly.
- It can also be used on cylindrical surfaces.
Surface gauges should not be used on the unleaded surface.
Marking tools in workshop are surface plate, marking table we will discuss this time.
Surface plate
Surface plate is made of malleable cast iron. It has been machined and scraped to a high degree of flatness. The flat surface is being used as a datum surface for marking out tools and for measuring purposes. If it can stand on the floor, it is called surface table.
It is made of cast iron, graphite or ceramic. Some surface plates are flat by lapping to a precision of 0.0025 mm.
It is used to test the flatness of other surfaces or marking off the work and used for inspection of jig and fixture as well as gauges.
Protection and Maintenance of the Surface Plate
- The upper surface of the surface plate should be kept clean and dust, rust and burrs should be removed.
- The surface plate should be shelved on three legs to prevent rocking and twisting. If it is shelved on four legs, there is a possibility of rocking and twisting.
- After working, the surface plate should be cleaned and lubricated oil or greased on it.
- Do not let any heavy objects fall on the surface plate.
Marking Table
Marking tables are used for supporting or setting up work vertically and are provided with holes and slots through which securing bolts can be located. It is made of cast iron and ground to a high degree of accuracy.
The marking table provides a reference plane on which the task and marking-out tools are placed. The task that needs to be identified is placed at a right angle to the reference plane.
When it cannot be used, it should be covered with a well-fitting wooden cover to protect it.
Vee Block
Vee blocks is A Marking Tool usually in a couple are made of cast iron or steel in case-hardening. They are generally used for holding circular workpiece for marking out or machining.
They consist of a rectangular steel or cast iron block with a 120 degree channel rotated 45-degrees from the sides, forming a V-shaped channel in the top
V blocks come in many sizes, most of which are used for drilling in out or round work fields. They are usually found in pairs and a ‘V’ shaped slot is made at a perfect 90 ° angle above and below it. Often comes a ‘U’ shaped clamp with which it is tightly tied to the work.
Types of V Block
According to Indian Standard (BIS) ‘V’ blocks are of the following four types:
1. Single Level Single Groove ‘V’ Block
It has only one ‘V’ groove and has single rectangular slots to position the holding clamps on either side.
2. Single Level Double Groove ‘V’ Block
It has a ‘V’ groove and two rectangular slots to position the holding clamps on either side.
3. Double Level Single Groove ‘V’ Block
It consists of two ‘V’ grooves at the top and bottom and a rectangular one on either side to accommodate the holding clamps.
4. Matched Pair ‘V’ Block
This type of ‘V’ block is found in pairs that have the same size and uniform precision. They are used to support long shafts.
Grade
‘V’ blocks are found in ‘A’ and ‘B’ grades. ‘V’ blocks with ‘A’ grade are more accurate and are found only up to 100 mm in length.
These are made of high-quality steel.
‘V’ blocks with ‘B’ grade are used for simple tasks and are found up to 500 mm in length.
These are made of closed grain cast iron.
Precautions
- Clean the ‘V’ block before and after use
- Avoid scratching the ‘V’ block.
- When they are not being used, apply a thin layer of oil or grease to them.
Angle Plate
Now next one marking tools in workshop are angle plates and bevel square which is used to mark at a particular angle.
An angle plate (figure 18) is used for supporting or setting up work vertically and is provided with holes and slots through which securing bolts can be located. It is made of cast iron and ground to a high degree of accuracy.
An angle plate is a work holding device used as a fixture in metalworking. Angle plates are used to hold workpieces square to the table during marking out operations. Adjustable angle plates are also available for workpieces that need to be inclined, usually towards a milling cutter.
Angle plates are found in various sizes which are in the range from 1 to 10 numbers.
Bevel Square
It is A adjustable tool used by carpenters to establish angles and to test the accuracy of working surfaces on slopes.
It is usually made of carbon steel and parallel ends are ground.
It varies slightly in size but has a blade that can be moved in 360 ° and locked in a fixed position.
Steel Rule
It is also a marking tool, We are all familiar with this, which is the simplest and most common measurement tool of a steel rule. The flat steel rule is usually 6 or 12 inches long, but taller sizes are available. Steel rules can be flexible or nonflexible, thin or wide. … Usually, a steel rule has four sets of symbols, two on each side of the rule. And light in weight so we can carry it very easily
Graduations are usually made in millimetres or half millimetres on the rule of a metric combination set.
Square Head
Square head is used to draw lines in parallel or right angles with an edge. It is used as a depth gauge or to check angles of 45° and 90 °. The square head can be moved to any position on the rule.
Protractor Head
Protractor head is used to check the layout of an angle. It has a spirit level to set up jobs in the horizontal plane.
Center Head
A center head is formed when a center square is fitted over it. It can be used for the location of center of round, square and octagonal stock.
