Q1: Holes for rivetting purposes should be preferably made by

ANS:B - drilling

Drilling is a machining process used to create holes in solid materials, such as metal, wood, plastic, and composites. It involves the use of a drill bit, which is a cutting tool with sharp edges, attached to a rotating spindle. The drill bit is pressed against the workpiece, and as it rotates, it removes material to form a hole. Here's how the drilling process typically works:

1. Selection of Drill Bit: The appropriate drill bit is selected based on the material being drilled, the size of the hole required, and other factors such as the desired hole geometry.
2. Securing the Workpiece: The workpiece is securely clamped or held in place to prevent movement during drilling. This ensures accuracy and safety during the process.
3. Aligning the Drill Bit: The drill bit is aligned with the desired location for the hole on the workpiece. This can be done manually using visual aids or with the help of machinery such as drill presses that provide precise positioning.
4. Applying Pressure: The drill bit is brought into contact with the workpiece, and pressure is applied to initiate the cutting action. The rotational speed and feed rate (rate at which the drill bit advances into the material) are controlled to optimize cutting efficiency and prevent overheating or tool wear.
5. Material Removal: As the drill bit rotates, its cutting edges engage with the workpiece material, removing material in the form of chips. The drill bit is gradually fed into the material to create the desired depth of the hole.
6. Chip Removal: Chips generated during drilling are cleared away from the cutting area to prevent them from interfering with the cutting process or causing damage to the workpiece or the drill bit.
7. Finishing and Deburrring: After drilling is complete, the hole may require deburring to remove any sharp edges or burrs left behind by the cutting process. This can be done using deburring tools or other methods to ensure a smooth and clean hole surface.

• Precise control over hole size and location.
• Versatility for drilling various materials and hole sizes.
• Ability to create holes with different geometries and depths.
• Relatively fast and efficient compared to other hole-making methods.