Aim:

To fabricate a conical funnel from a G.I. (Galvanized Iron) sheet using fundamental sheet metal operations. 

Materials & Tools Required:

• Sheet Metal (Galvanized Iron (G.I.)) of sheet thickness 25 gauge  = 0.54mm

• Measuring Tools: Steel rule, divider, scriber, Try square, Standard wire gauge

• Cutting Tools: Tin Snips (Straight & Curved)

• Forming Tools: Bench vice, Funnel Stake, wooden mallet or ball peen hammer.

• Joining Tools: Rivets (if required)

• Finishing Tools: File, Emery paper (if required)

• Surface Cleaning material: Cotton Waste (if required)

Operations:

1. Measuring and Marking

2. Cutting (Snipping)

3. Bending (Angle Bending, U-Bending, V-Bending, Edge Bending)

4. Folding

5. Riveting (if needed)

6. Rolling (if needed)

7. Joining (Spot Welding) (if needed)

8. Finishing (Polishing, Surface Coating) (if required)

Procedure:

1. Clean the G.I sheet using cotton waste to remove dust, oil, or rust for accurate marking and cutting.

2. Measure the size of the sheet with a steel rule to ensure it is large enough to develop the required conical funnel.

3. If the sheet has bends or irregularities, use a wooden mallet to flatten it, ensuring a smooth surface for accurate marking.

4. For developing the conical funnel, mark the lines on GI sheet for sector shape (conical shape) and cylindrical spout (small outlet section)

5. Cut the sheet along the marked lines using tin snips (straight and curved) to form the sector shape for the conical portion and the rectangular strip for the cylindrical outlet. If necessary, smoothen the edges using a metal file and emery paper.

6. Form the conical shape using funnel stake and a ball peen hammer or mallet based on guage of the sheet by gradually roll the sector into a conical shape by bending it around a funnel stake and align the edges carefully to maintain the correct shape and fit.

7. Form the cylindrical spout (outlet section) by rolling the rectangular strip into a cylinderical shape and join its edges using rivets.

8. Attach the spout to the narrow end of the cone by cutting a small circular hole (equal to outlet diameter) at the narrow end of the cone and then Insert the cylindrical spout into the hole and fix it with rivets .

 9. Final process is to check the dimensions and shape of the funnel, use emery paper to smooth sharp edges and ensure the joint is strong and leak-proof.

Precautions:

1. Use safety gloves while handling sharp sheet edges.

2. Mark accurately before cutting or bending.

3. Apply even force while bending to avoid shape distortions.

4. Check riveting or soldering joints to ensure durability.

Result:

A conical funnel is successfully fabricated using sheet metal operations, maintaining the required dimensions and shape.