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Questions and Answers about CNC programming


 Q1: What is CNC programming?

Ans: CNC programming is the process of creating instructions, typically in the form of G-code, that are used to control computer numerical control (CNC) machines. These instructions tell the machine how to move, position, and perform various machining operations on a workpiece.

Q2: What is G-code?
Ans: G-code is a programming language used to control CNC machines. It consists of a series of commands that specify the machine's movements, such as positioning, tool selection, cutting speeds, and feed rates.

Q3: How is CNC programming different from manual programming?
Ans: In manual programming, the operator directly controls the machine by inputting individual commands and coordinates. CNC programming, on the other hand, involves creating a program that automates the machine's movements, allowing for more complex and precise machining operations.

Q4: What are the basic components of a CNC program?
Ans: A CNC program typically consists of blocks of G-code commands. Each block starts with a letter (e.g., G, M) followed by a number or numbers that define specific actions or operations. These blocks are organized sequentially to guide the machine's movements and actions.

Q5: What is the purpose of the G-code command "G01"?
Ans: The G01 command is used for linear interpolation or straight line cutting. It specifies that the machine should move in a straight line from one point to another at a given feed rate.

Q6: What is the purpose of the G-code command "G02" and "G03"?
Ans: The G02 and G03 commands are used for circular interpolation. G02 specifies a clockwise circular movement, while G03 specifies a counterclockwise circular movement. These commands are used for creating arcs or circles in CNC machining.

Q7: What is the difference between absolute and incremental programming?
Ans: In absolute programming, coordinates are specified with reference to a fixed point, usually the machine's origin. The absolute position of the tool is defined for each movement. In incremental programming, coordinates are given as distances from the current position. Each movement is relative to the previous position.

Q8: What is a tool offset in CNC programming?
Ans: Tool offset is an adjustment made to the tool's position to compensate for variations in tool dimensions and achieve accurate machining. It allows the programmer to specify the desired cutting tool's effective position relative to the workpiece.

Q9: How can you handle tool changes in a CNC program?
Ans: Tool changes are typically handled using the M06 command in G-code. This command is used to call for a tool change and specify the tool number. The machine will then stop, allowing the operator to change the tool, and resume machining with the new tool.

Q10: What is a subprogram in CNC programming?
Ans: A subprogram, also known as a subroutine or macro, is a sequence of CNC program blocks that perform a specific task. Subprograms can be called from the main program, allowing for modular programming and code reuse.

Q11: What is the purpose of the M03 and M05 commands in G-code?
Ans: The M03 command is used to start the spindle rotation in a clockwise direction, while the M05 command is used to stop the spindle rotation. These commands are essential for controlling the cutting tool's rotation during machining operations.
Ans:
Q12: How can you control the feed rate in CNC programming?
Ans: The feed rate is controlled using the F command in G-code. It specifies the speed at which the cutting tool moves along the programmed path. For example, the command "F100" sets the feed rate to 100 units per minute.

Q13: What is the difference between a modal and a non-modal G-code command?
Ans: A modal G-code command remains in effect until another command of the same type is encountered or a reset command is given. It affects all subsequent movements until changed. Non-modal commands, on the other hand, affect only the next movement or operation and do not have a persistent effect.

Q14: How can you specify dwell time in a CNC program?
Ans: Dwell time refers to a pause or delay at a specific point during machining. It is achieved using the G04 command followed by a numerical value that represents the time in seconds. For example, "G04 P2.5" would introduce a dwell time of 2.5 seconds.

Q15: What is the purpose of the G28 command?
Ans: The G28 command is used to move the machine to its reference or home position. It is commonly used at the beginning or end of a program to establish a known starting point for the machine.

Q16: How can you program drilling operations in CNC?
Ans: Drilling operations can be programmed using the G81 command in G-code. This command specifies the start position, drilling depth, feed rate, and retract height for the drill.

Q17: What is the difference between a roughing and a finishing operation in CNC machining?
Ans: Roughing operations involve removing large amounts of material quickly, typically using larger cutting depths and higher feed rates. Finishing operations, on the other hand, are performed to achieve a high level of surface finish and accuracy, often using smaller cutting depths and slower feed rates.

Q18: What are the benefits of using canned cycles in CNC programming?
Ans: Canned cycles are pre-programmed sequences of G-code commands that automate common machining operations. They provide a simplified and efficient way to program complex operations such as drilling, tapping, and boring, reducing programming time and improving accuracy.

Q19: How can you program tool radius compensation in CNC?
Ans: Tool radius compensation, often referred to as cutter compensation, is programmed using the G41 or G42 command in G-code. G41 activates compensation to the left of the tool path, while G42 activates compensation to the right. The command is followed by the tool's radius value.

Q20: What is the purpose of the M30 command in CNC programming?
Ans: The M30 command is used to end a program and return the machine to its reference or home position. It is typically placed at the end of a CNC program to signify its completion.

Q21: What is the difference between a G02 and G03 command in circular interpolation?
Ans: The G02 command specifies a clockwise circular interpolation, while the G03 command specifies a counterclockwise circular interpolation. The two commands are used to create arcs or circles in CNC machining.

Q22: What is the purpose of the G90 and G91 commands in CNC programming?
Ans: The G90 command sets the machine to absolute programming mode, where coordinates are defined with respect to a fixed reference point. The G91 command sets the machine to incremental programming mode, where coordinates are given as distances from the current position.

Q23: How can you program a tool change in the middle of a CNC program?
Ans: To program a tool change in the middle of a CNC program, you can use the M06 command followed by the tool number. For example, "M06 T02" would call for a tool change to tool number 2.

Q24: What is the purpose of the G54-G59 work offsets in CNC programming?
Ans: The G54-G59 work offsets allow you to set multiple reference points on a machine. Each work offset represents a different coordinate system, enabling you to easily switch between different setups or workpieces.

Q25: How can you program a rectangular pocket milling operation in CNC?
Ans: To program a rectangular pocket milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and G41/G42. These commands are used to specify the tool's path, cutting depths, and tool compensation, if necessary.

Q26: What is a peck drilling cycle in CNC programming?
Ans: A peck drilling cycle is used when drilling deep holes to prevent chip buildup and facilitate chip evacuation. It involves drilling to a certain depth, retracting the drill bit, and then repeating the process until the desired hole depth is reached. The G83 command is commonly used for peck drilling.

Q27: What is the purpose of the G68 and G69 commands in CNC programming?
Ans: The G68 command is used to rotate the coordinate system in a specified plane. It allows you to program machining operations at angles other than the machine's default orientation. The G69 command is used to cancel the coordinate system rotation and restore the default orientation.

Q28: How can you program a thread milling operation in CNC?
Ans: Thread milling can be programmed using a combination of circular interpolation (G02/G03), linear interpolation (G01), and multiple passes with varying depths. The specific thread parameters such as pitch, depth, and feed rate are defined in the program.

Q29: What is the difference between a rapid traverse (G00) and a feed move (G01) in CNC programming?
Ans: A rapid traverse (G00) is a fast movement of the machine tool to quickly position the tool without cutting. It moves the machine at its maximum rapid traverse rate. A feed move (G01) is a controlled movement where the machine moves at a specified feed rate while cutting material.

Q30: What are the safety considerations in CNC programming?
Ans: Safety is of utmost importance in CNC programming. Some key considerations include ensuring proper machine setup, using correct tooling, defining appropriate work and tool offsets, verifying clearances, and implementing safe retract heights. Following safety guidelines and protocols is essential to prevent accidents and protect personnel.

Q31: What is the purpose of the G40 command in CNC programming?
Ans: The G40 command is used to cancel tool radius compensation. It ensures that the tool follows the exact path specified in the program without any additional offset due to tool radius compensation.

Q32: How can you program a chamfer operation in CNC machining?
Ans: To program a chamfer operation, you can use a combination of linear interpolation (G01) and circular interpolation (G02/G03) commands. By specifying the start and end points of the chamfer and the desired chamfer angle, you can create the desired chamfered edge.

Q33: What is the purpose of the G92 command in CNC programming?
Ans: The G92 command is used to set temporary work offsets. It allows you to define new coordinate values for the machine without changing the permanent work offsets (G54-G59). This can be useful for creating custom coordinate systems or for aligning the machine with a specific feature on the workpiece.

Q34: What is a dwell cycle in CNC programming?
Ans: A dwell cycle is used to introduce a controlled pause or delay at a specific point in the program. It is typically achieved using the G04 command followed by a time value. During the dwell, the machine maintains its current position without any movement.

Q35: How can you program a facing operation in CNC machining?
Ans: To program a facing operation, you can use linear interpolation (G01) or rapid traverse (G00) commands along with appropriate feed rates and depths of cut. The tool is moved across the workpiece in a straight line to create a flat surface.

Q36: What is the purpose of the G98 and G99 commands in CNC programming?
Ans: The G98 command is used to specify that the machine should retract to a reference plane after each drilling cycle. It is typically used when drilling multiple holes at different depths. The G99 command, on the other hand, specifies that the machine should retract to a predefined level above the workpiece after each drilling cycle.

Q37: How can you program a tapping operation in CNC machining?
Ans: Tapping operations can be programmed using a combination of linear interpolation (G01) or rapid traverse (G00) commands, appropriate feed rates, spindle speeds, and tapping cycles (M29 or M33). The program specifies the tapping depth, pitch, and any necessary dwell time for the tapping operation.

Q38: What is the purpose of the M02 command in CNC programming?
Ans: The M02 command is used to end a program and stop the CNC machine. It is similar to the M30 command but may have different functionalities depending on the specific CNC control system.

Q39: How can you program a helical interpolation operation in CNC machining?
Ans: To program a helical interpolation operation, you can use a combination of linear interpolation (G01), circular interpolation (G02/G03), and Z-axis movements. By specifying the start point, end point, helix radius, pitch, and direction, you can create a helical path for the cutting tool.

Q40: What are the common programming mistakes to avoid in CNC programming?
Ans: Some common programming mistakes to avoid in CNC programming include incorrect tool selection, improper tool paths, forgetting to account for tool radius compensation, incorrect feed rates or spindle speeds, incomplete or missing commands, and incorrect use of work offsets. It is important to thoroughly review and simulate the program before running it on the machine.

Q41: What is the purpose of the G43 command in CNC programming?
Ans: The G43 command is used to enable tool length compensation. It allows the machine to adjust the Z-axis position automatically based on the length of the currently used tool, ensuring accurate machining operations.

Q42: How can you program a pocket milling operation in CNC machining?
Ans: To program a pocket milling operation, you can use a combination of linear interpolation (G01), circular interpolation (G02/G03), and appropriate feed rates and depths of cut. By specifying the boundary of the pocket and the desired tool path, you can remove material efficiently.

Q43: What is the difference between climb milling and conventional milling?
Ans: In climb milling, the cutting tool rotates in the same direction as the workpiece feed direction. This results in the tool "climbing" into the material, offering reduced cutting forces and smoother finishes. In conventional milling, the tool rotates against the direction of the workpiece feed, leading to higher cutting forces but potentially faster material removal.

Q44: How can you program a contour milling operation in CNC machining?
Ans: To program a contour milling operation, you can use a combination of linear interpolation (G01), circular interpolation (G02/G03), and appropriate feed rates and depths of cut. By specifying the desired contour and tool path, you can accurately shape the workpiece.

Q45: What is a dwell time and how is it programmed in CNC?
Ans: Dwell time refers to a specific pause or delay at a particular point in the program. It is often used for purposes such as chip evacuation, tool cooling, or allowing the workpiece to settle. Dwell time can be programmed using the G04 command followed by a time value.

Q46: What is the purpose of the M08 and M09 commands in CNC programming?
Ans: The M08 command is used to start the machine coolant or flood coolant system, ensuring proper cooling and lubrication during machining. The M09 command is used to stop the coolant flow.

Q47: How can you program a 3D contour milling operation in CNC machining?
Ans: To program a 3D contour milling operation, you can use a combination of linear interpolation (G01), circular interpolation (G02/G03), and Z-axis movements. By specifying the desired contour and tool path in three dimensions, you can create complex shapes and surfaces.

Q48: What is the purpose of the G54.1 P1 command in CNC programming?
Ans: The G54.1 P1 command is used to specify a secondary workpiece coordinate system. It allows for additional reference points and coordinate systems to be defined, providing flexibility in complex machining setups.

Q49: How can you program a drilling cycle with pecking and chip breaking in CNC machining?
Ans: To program a drilling cycle with pecking and chip breaking, you can use the G83 command with additional parameters. By specifying the peck depth, retraction distance, and number of pecks, you can automate the drilling process while ensuring chip evacuation.

Q50: What are some important considerations for optimizing CNC programs?
Ans: To optimize CNC programs, it is important to reduce unnecessary tool movements, minimize rapid traverses, and use efficient tool paths. Other considerations include selecting appropriate cutting parameters, optimizing tool changes, utilizing canned cycles and subprograms, and minimizing tool idle time. These optimizations help improve machining efficiency and reduce cycle times.

Q51: What is the purpose of the G54-G59.3 commands in CNC programming?
Ans: The G54-G59.3 commands are used to define work coordinate systems (WCS) on a CNC machine. These commands allow you to set specific reference points and coordinate systems for different parts or setups, enabling precise positioning and machining operations.

Q52: How can you program a thread cutting operation in CNC machining?
Ans: To program a thread cutting operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and G76 or G92. These commands are used to specify the starting point, thread pitch, depth, and other parameters required for cutting threads.

Q53: What is the purpose of the G10 command in CNC programming?
Ans: The G10 command is used to program tool offsets or tool compensation values directly into the CNC machine's memory. It allows you to set and modify tool length, diameter, and wear offsets, ensuring accurate machining without modifying the program.

Q54: How can you program a contour following operation in CNC machining?
Ans: To program a contour following operation, you can use a combination of G-code commands such as G01, G02/G03, G41/G42, and G61/G64. These commands are used to specify the tool path, tool compensation, and motion smoothing for following complex contours.

Q55: What is the purpose of the M06 command in CNC programming?
Ans: The M06 command is used to perform an automatic tool change during a CNC machining operation. It prompts the machine to stop, change the tool, and resume machining with the newly loaded tool.

Q56: How can you program a boring operation in CNC machining?
Ans: To program a boring operation, you can use a combination of G-code commands such as G00, G01, G41/G42, and G83. These commands are used to specify the starting point, cutting parameters, tool compensation, and pecking cycles required for boring holes.

Q57: What is the purpose of the G92.1 command in CNC programming?
Ans: The G92.1 command is used to cancel temporary work offsets and return the machine to the original work coordinate system. It clears any temporary coordinate system changes made using the G92 command.

Q58: How can you program a multi-pass milling operation in CNC machining?
Ans: To program a multi-pass milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and multiple passes at different depths of cut. By specifying the tool path, cutting parameters, and number of passes, you can efficiently remove material in stages.

Q59: What is the purpose of the G53 command in CNC programming?
Ans: The G53 command is used to move the machine's axes to a specific position in machine coordinates. Unlike other positioning commands, the G53 command ignores any coordinate system offsets and directly moves the machine to the specified location.

Q60: How can you program a reaming operation in CNC machining?
Ans: To program a reaming operation, you can use a combination of G-code commands such as G00, G01, and G85. These commands are used to specify the starting point, cutting parameters, and dwell time required for accurately reaming a hole.

Q61: What is the purpose of the G50 command in CNC programming?
Ans: The G50 command is used to set the maximum spindle speed limit. It allows you to specify a maximum RPM value for the spindle, ensuring safe and controlled operation.

Q62: How can you program a contour pocket milling operation in CNC machining?
Ans: To program a contour pocket milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and G41/G42. These commands are used to specify the tool path, cutting parameters, and tool compensation required for machining a contoured pocket.

Q63: What is the purpose of the G47 command in CNC programming?
Ans: The G47 command is used to perform a facing operation with a specified angle. It allows you to create flat surfaces at an angle to the workpiece by controlling the tool's orientation during the facing operation.

Q64: How can you program a rigid tapping operation in CNC machining?
Ans: To program a rigid tapping operation, you can use a combination of G-code commands such as G00, G01, and G84. These commands are used to specify the tapping parameters, such as feed rate, spindle speed, and tapping depth, to create threaded holes accurately.

Q65: What is the purpose of the G92.2 command in CNC programming?
Ans: The G92.2 command is used to offset the current position of the machine. It allows you to define temporary work offsets by specifying the desired coordinate values, providing flexibility in positioning and machining operations.

Q66: How can you program a helical ramping operation in CNC machining?
Ans: To program a helical ramping operation, you can use a combination of G-code commands such as G01, G02/G03, and Z-axis movements. By specifying the desired helix parameters, such as pitch, diameter, and ramping angle, you can create helical toolpaths for efficient material removal.

Q67: What is the purpose of the G92.3 command in CNC programming?
Ans: The G92.3 command is used to cancel the offset values set by the G92 command. It allows you to revert the machine to its original coordinate system, eliminating any temporary offsets.

Q68: How can you program a corner rounding operation in CNC machining?
Ans: To program a corner rounding operation, you can use a combination of G-code commands such as G01, G02/G03, and tool radius compensation (G41/G42). These commands are used to specify the tool path and compensate for the tool's radius, creating rounded corners with the desired radius.

Q69: What is the purpose of the G61 command in CNC programming?
Ans: The G61 command is used to set the exact stop mode. It ensures that the machine stops precisely at each programmed point, allowing for accurate positioning and control during machining operations.

Q70: How can you program a pocket island milling operation in CNC machining?
Ans: To program a pocket island milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and multiple passes at different depths. By defining the boundaries of the island and the tool path, you can create pockets with islands inside them.

Q71: What is the purpose of the G68 command in CNC programming?
Ans: The G68 command is used to rotate the coordinate system in the machine. It allows you to machine features at different angles without physically repositioning the workpiece.

Q72: How can you program a thread milling operation in CNC machining?
Ans: To program a thread milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and G92. These commands are used to specify the tool path, thread pitch, start point, and other parameters required for milling threads.

Q73: What is the purpose of the G54.2 command in CNC programming?
Ans: The G54.2 command is used to set the additional work coordinate system offset. It allows you to define an additional offset from the main work coordinate system, providing flexibility in positioning and machining operations.

Q74: How can you program a contour roughing operation in CNC machining?
Ans: To program a contour roughing operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and multiple passes at varying depths of cut. By specifying the tool path and cutting parameters, you can remove excess material quickly and efficiently.

Q75: What is the purpose of the M03 command in CNC programming?
Ans: The M03 command is used to start the spindle rotation in the clockwise direction. It activates the spindle motor, enabling it to rotate the cutting tool during machining operations.

Q76: How can you program a profile milling operation in CNC machining?
Ans: To program a profile milling operation, you can use a combination of G-code commands such as G00, G01, and G02/G03. These commands are used to specify the tool path, cutting parameters, and the desired profile, allowing you to accurately shape the workpiece.

Q77: What is the purpose of the G43.1 command in CNC programming?
Ans: The G43.1 command is used to enable tool length compensation with a tool length offset. It allows the machine to automatically adjust the Z-axis position based on the length of the currently used tool, ensuring precise machining.

Q78: How can you program a recessing operation in CNC machining?
Ans: To program a recessing operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and tool radius compensation (G41/G42). By specifying the recess dimensions and tool path, you can create recessed features accurately.

Q79: What is the purpose of the M05 command in CNC programming?
Ans: The M05 command is used to stop the spindle rotation. It deactivates the spindle motor, bringing it to a halt.

Q80: How can you program a pocket profiling operation in CNC machining?
Ans: To program a pocket profiling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and tool radius compensation (G41/G42). These commands are used to specify the pocket boundary, tool path, and cutting parameters for accurate pocket profiling.

Q81: What is the purpose of the G92.4 command in CNC programming?
Ans: The G92.4 command is used to cancel the offset values set by the G92.1 command. It allows you to revert the machine to its original coordinate system, eliminating any temporary work offsets.

Q82: How can you program a chamfer milling operation in CNC machining?
Ans: To program a chamfer milling operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and tool radius compensation (G41/G42). These commands are used to specify the tool path and cutting parameters for creating chamfered edges with the desired angle and dimensions.

Q83: What is the purpose of the G28 command in CNC programming?
Ans: The G28 command is used to return the machine to the home position or a predefined reference point. It moves all axes to their respective reference positions, allowing for consistent starting points in CNC machining.

Q84: How can you program a facing operation in CNC machining?
Ans: To program a facing operation, you can use a combination of G-code commands such as G00, G01, and G94. These commands are used to specify the tool path, feed rate, and depth of cut, enabling you to create flat surfaces on the workpiece.

Q85: What is the purpose of the G43.4 command in CNC programming?
Ans: The G43.4 command is used to enable tool length compensation with a dynamic tool length offset. It allows for automatic adjustment of the Z-axis position based on the length of the currently used tool during machining operations.

Q86: How can you program a helical interpolation operation in CNC machining?
Ans: To program a helical interpolation operation, you can use a combination of G-code commands such as G01, G02/G03, and Z-axis movements. By specifying the helix parameters, such as pitch, diameter, and number of turns, you can create helical toolpaths for drilling or milling operations.

Q87: What is the purpose of the G50.1 command in CNC programming?
Ans: The G50.1 command is used to reset the maximum feed rate limit. It allows you to override or modify the default feed rate limit set by the machine, enabling adjustments for specific machining operations.

Q88: How can you program a contour engraving operation in CNC machining?
Ans: To program a contour engraving operation, you can use a combination of G-code commands such as G00, G01, G02/G03, and tool radius compensation (G41/G42). These commands are used to specify the desired engraving pattern, tool path, and cutting parameters for precise engraving on the workpiece.

Q89: What is the purpose of the M02 command in CNC programming?
Ans: The M02 command is used to end the program and stop the CNC machine. It serves as the program termination command, indicating the completion of the machining operation.

Q90: How can you program a slot milling operation in CNC machining?
Ans: To program a slot milling operation, you can use a combination of G-code commands such as G00, G01, and G41/G42. These commands are used to specify the tool path, feed rate, and width of the slot, allowing you to machine slots with precise dimensions.

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Experiment No.:                                                                                      Date: SINGLE ‘V’ BUTT JOINT Aim: To prepare a single ‘V’ Butt Joint as per dimensions given in the sketch. Material Required: Mild Steel plates: 80mm X 40mm X 6mm = 2 Nos Mild Steel electrode ¢ 3.15 mm Equipment required: A.C. Transformer with all welding accessories like Electrode holder, cables. Tool Required: Steel rule 300mm  Scriber 150mm Flat file 300mm Try square 200mm Flat Tong 450mm  Chipping hammer 200mm Ball peen hammer 750mm  Wire brush Welding screen Sequence of Operations: 1. Marking  2. Filing  3. Welding  4. Finishing Procedure: Take two Mild steel plates of size 80mm X 40mm X 6mm. Fix the wor...

Welding-LAP JOINT

Ex. No :                                                                              Date : LAP JOINT Aim To join the given two work pieces as a lap joint by arc welding. Material used Mild Steel plates. Tools required Welding power supply  Flat file Welding rod Chipping hammer Electrode holder Wire brush Gloves and apron Earthing clamps Shield and goggles Procedure The given workpieces are thoroughly cleaned, i.e. rust, scales are removed and the  edges are filed. The electrode is held in an electrode holder and ground clamp is clamped to the  welding plates and the power is supplied. The workpieces are positioned on the table to form a “Lab joint”. The tag weld is done on the both the ends of joining plates to avoid the m...

Welding-TEE FILLET JOINT

Ex. No :                                                                                 Date : TEE FILLET JOINT Aim To join the given two work pieces as a ‘Tee fillet joint’ by arc Welding. Material used Mild steel plates. Tools required • Welding power supply • Flat file • Welding rod • Chipping hammer • Electrode holder • Wire brush • Gloves and apron  • Earthing clamps • Shield and goggles Procedure The given workpieces are thoroughly cleaned, i.e. rust, scales are removed and the  edges are filed. The electrode is held in an electrode holder and ground clamp is clamped to the  welding plates and the power is supplied. The workpieces are positioned on the table to form a “Tee fillet joint”. The tag weld is done on the bo...

sheet metal rectangular tray making

Aim :- To make a rectangular tray from a given metallic sheet. Tools Required MALLET Snip Stake STEEL RULE Ball peen HAMMER Straight EDGE RIVETS Scriber Procedure The given metal sheet is smoothed using mallet. The measurements of rectangular tray (tray development drawing) is drawn on the sheet with given dimensions using the scriber and steel rule. The sheet is cut as per the marked dimensions by straight snips. Fold or bend as per the given order using mallet and stake. Bending is done as per the given dimension using the stake and mallet. Rivet the folded sheet by using the given rivets and hammer. Safety Precautions Each cut you make exposes sharp edges and creates burrs that can slice a finger. Must Use Hand gloves when cutting the sheet. Metal waste also has hazardous edges. So...

Sheet metal Funnel making

Making a Funnel using metallic sheet Making a Funnel using metallic sheet Aim:- To make a funnel from a given (GI)metallic sheet. Tools Required:- MALLET, SNIP, STAKE, STEEL RULE, BALL PEEN HAMMER, STRAIGHT EDGE, RIVETS, SCRIBER Procedure:  The size of the given sheet metal is checked for its dimensions using a steel rule The required development of surface is being made on the white paper which is overlapped on the sheet metal. The marking is done on the sheet metal as per the development being done on the paper. Now using straight snips, unwanted materials are removed. Now fold and bend the workpiece to make the funnel shape and joint is made on the workpieces. Then using a groover, a locked grooved joint is made for about 5mm. Also, hemming is done in the bottom of the funnel. In between top face and bottom face, a butt joint is made using a solder. Finally, trimming and finishing operations are carried out. Safety Precautions:- Each cut you make exposes s...

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