A nail gun is an indispensable tool for carpentry projects, and when it comes to installing door trim, it can significantly streamline the process. In this guide, we’ll provide clear and concise instructions on how to efficiently install door trim using a nail gun, catering to both professionals and DIY enthusiasts.

1. Choosing the Right Nail Gun:
   Select a finish nail gun with a gauge between 15 and 18 for door trim installation. This ensures the nails are robust enough to hold the trim securely without causing splits.

2. Selecting the Right Nails:
   Use finish nails of an appropriate length, typically ranging from 2 to 2.5 inches. Ensure the nails are compatible with your nail gun and are designed for trim applications.

3. Safety First:
   Prioritize safety by wearing protective gear, including safety glasses. Disconnect the nail gun from the power source when not in use.

4. Preparing the Door and Trim:
   a. Cut the door trim pieces to the required lengths, making precise 45-degree miter cuts for corners.
   b. Sand the edges for a smooth finish.

5. Positioning the Trim:
   a. Start in a corner and position the first piece of door trim flush against the wall.
   b. Ensure the top edge is level, adjusting as needed.

6. Loading the Nail Gun:
   a. Open the magazine of the nail gun.
   b. Insert the finish nails according to the manufacturer’s instructions.
   c. Close and latch the magazine securely.

7. Setting the Nail Gun Depth:
   Adjust the depth setting on the nail gun to ensure the nails are driven flush with the surface of the trim. Test the depth on scrap material before starting the installation.

8. Firing the Nail Gun:
   a. Hold the nail gun at a slight angle, about 15 degrees.
   b. Place the nail gun tip onto the trim and press the trigger.
   c. Drive nails at regular intervals, typically every 12 to 16 inches along the length of the trim.

9. Securing Corners:
   a. For inside corners, use the nail gun to secure one trim piece before attaching the adjoining piece.
   b. For outside corners, secure one piece first, then overlap and secure the second piece.

10. Filling Nail Holes:
    Fill the nail holes with wood putty or filler. Sand the filled areas for a smooth finish.

11. Final Checks:
    a. Ensure all nails are driven flush.
    b. Check for any gaps or uneven seams and make adjustments as necessary.

12. Cleaning Up:
    Dispose of waste materials, and store the nail gun properly.

Conclusion:
Installing door trim with a nail gun is a straightforward process that significantly speeds up the project while delivering professional results. By following these clear and concise steps, you can confidently use a nail gun to install door trim, enhancing the aesthetics of your space. Always prioritize safety, consult the user manual for your specific nail gun model, and enjoy the efficiency and precision that a nail gun brings to your carpentry projects.