The question is slightly unclear. It could mean:
- How to repair a thread on a bolt that is damaged. This involves using tools to reshape the existing, damaged threads.
- How to create a thread in a hole so you can screw a bolt into it. This is done using a tap and die set.
Because the reference document refers to drilling and tapping a hole, this answer will focus on the second interpretation: how to create a thread in a hole so that a bolt can be screwed into it.
Here are the steps to create a threaded hole for a bolt:
Steps to Create a Threaded Hole for a Bolt
- Determine the Correct Drill Size:
- You'll need to choose a drill bit that's the correct size for the bolt you intend to use. The correct drill size depends on the bolt's major diameter and thread pitch. Consult a tap drill chart for the correct drill size for the specific bolt you are using.
- Determine the Correct Tap:
- Select the tap that matches the size and thread pitch of the bolt you want to use. The tap is the tool that will cut the threads into the hole. Tap sizes are typically marked with diameter and threads per inch (TPI), or by metric designation.
- Tap the Hole:
- After drilling the hole, use the tap to create the threads.
- Start by carefully aligning the tap with the hole.
- Apply downward pressure and turn the tap clockwise.
- For steel, after each turn, rotate the tap backwards to break the chip.
- Use cutting fluid for a smoother thread.
- Continue until the tap has passed through the entire hole.
- After drilling the hole, use the tap to create the threads.
- Test the Hole:
- Try screwing the bolt into the newly threaded hole to ensure it fits properly and the threads are clean. If the bolt is difficult to turn, run the tap through again to clean up the threads.
