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Today I will Share About Marking Tools(Marking Out Tools) used in the Workshop
Marking Tools is the most important Tool in Mechanical Engineering Manufacturing Process. Read This Article Carefully. Then You Know about Marking Tools
In gas welding, gas welding flame plays a very most important role so before knowing the types of gas welding flame. firstly we have collated some Idea what is flame in gas welding?
So, without wasting your time let’s Jump Today Topic types of Marking Tools(Marking Out Tools)
What is Marking Tool?
The marking tool is used to mark on a job or workpiece to obtain accurate size and shape.
Before using marking tools on a job or workpiece, firstly we should use marking media on it so that we can clearly see when marking.
Marking tool is also called as a marking out tools.
Types of Marking Tool
There are following types of marking tools in workshop
- Surface Gauge
- Surface Plate
- Marking Table
- Prick Punch
- Center Punch
- Hermaphrodite Caliper
- ‘V‘ – Block
- Angle Plates
- Bevel Square
- Combination Set
A surface gauge is a marking tool or marking out tools which is used to draw a lines of layout work by placing them on a surface plate.
There are two types of surface gauges
- Fixed Type Surface Gauge
- Universal Surface Gauge
Fixed Type Surface Gauge
Its design consists of a heavy base and a spindle that is a straight fix and It is fitted with a scriber with a snug and a clamp nut.
Universal Surface Gauge
This surface gauge has the following additional features.
- Can set the spindle in any position
- Fine adjustment can be made quickly.
- It can also be used on cylindrical surfaces.
Surface gauges should not be used on the unleaded surface.
After surface gauge next marking tools in workshop are surface plate, marking table with images.
This is a precision machined surfaces.
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.
This is made from closed-grain cast iron and is given special heat treatment so that it does not change its size after use.
The marking table provides a reference plane on which the task and marking-out tools are placed. The work that needs to be marked, is placed at a right angle with the reference plane.
When it is not to be used, it should be covered with a well-fitting wooden cover to protect it.
|Marking Tool: Surface Plate, Marking Table
After this, next marking tools in workshop to know scriber, prick punch, center punch with their images.
This hardened tool is a sharp tool made of steel which is used to draw lines while marking on a metal job.
It has a Conical Point (top angle usually 159°) and a Knurled Body.
The scriber should always be slanted in the direction of the movement and move with the appropriate pressure along the steel rule.
Its edge should always be pointed.
Scriber’s points are sharp edged, so it should be used carefully.
Scribers should not be kept in the pocket.
If it is not being used, cork should be applied on its point which can prevent the accident.
A prick punch is a layout marking tool or marking out tools which is made of steel, approximately 100 mm to 150 mm.
It is long, with both ends hard and tempered. Its point is grinded in an angle of 30 ° to 60 °. It is used to place small dots on layout lines, punch marks on the center of drill holes.
It is like a prick punch but its point is grinded in an angle of about 90 °.
This is used to make the marks larger than the prick punch because the point of the drill sits easily in it and the drill can be easily done with precision.
Some center punches are automatic with a striking mechanism in the handle.
The downward pressure of the striking mechanism is released into the handle to form the mark.
|Marking Tools:Scriber,Prick Punch,Center Punch|
Now we will know marking tools in workshop step by step are a divider, trammel and hermaphrodite caliper which is used to mark circles or used for marking on a round job.
This is a marking tool or marking out tools used to mark circles, segments and other geometrical textures.
- Measuring distance between two points.
- Direct transfer of measurements from steel rule.
- Marking circles and arcs on metal jobs.
According to the job, the points of trammel in length are associated with a bar.
It is used to draw circles and circles with more radiuses that cannot be drawn by a divider.
The hermaphrodite caliper is often used to find the center of the end of a round work or work that is cast and not completely round.
It is also known as Jenny Caliper.
- It is used for marking the parallel lines of inner and outer edges.
- It is used to locate the center of round bars.
- When setting the dimensions and drawing lines, both legs of Jenny Caliper should be the same length.
- For an accurate setting of dimensions, the point of Jenny Caliper should be clicked in graduation of steel rule.
|Divider and Trammel
‘V‘ – Block
V ‘blocks are often made of hardened steel or cast iron, which are found in many sizes. These are often used for drilling on lay outs or round work. They are usually found in pairs and have a ‘V‘ shaped slot machined in a perfect 90 ° angle at its top and bottom. Often a ‘U‘ shaped clamp comes with it tied tightly to the work.
|‘V‘ – Block|
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.
‘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.
- 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.
Now next one marking tools in workshop are angle plates and bevel square which is used to mark at a particular angle.
Angle plates are used to hold the work in parallel and right angles to the surface.
A ‘C‘ clamp device is often used to hold the work on the angle plate. Some angle plates have slots and tapped holes to hold the work.
Angle plates are found in various sizes which are in the range from 1 to 10 numbers.
Use of this marking tool or marking out tools in a fitting shop to mark a given angle with an edge or to check the angular precision of oblique surfaces.
It is usually made of carbon steel and parallel ends are grinded.
It varies slightly in size but has a blade that can be moved in 360 ° and locked in a fixed position.
|Angle Plate and Bevel Square|
Parallels are square or rectangular high steel bars whose surfaces are square and parallel grinded. These are in pairs and are used to raise the work to the correct height and provide a solid seat while layout.
Combination set is used for marking out and taking measurements. It is usually made of alloy steel. Its measuring faces are well-grinded.
This set consists of four main parts are steel rule, square head, protractor head and center head.
Steel rule can be fitted in center head, protractor head or square head. Sometimes it is used as a straight edge or for taking measurements.
Graduations are usually made in millimetres or half millimetres on the rule of a metric combination set.
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 is used to check the layout of an angle. It has a spirit level to set up jobs in the horizontal plane.
A center head is formed when a center square is fitted over it. It can be used for location of center of round, square and octagonal stock.
So friends here I discussed all aspects related to marking tools in workshop.
If any doubt you can ask me through comment or directly mail to me.