TECHNICAL DRAWING & ALPHABET OF LINE | SchoolWorkHelper - Free Printable

The image provided is a standard line convention chart used in technical drawing and engineering drafting. This chart defines the types of lines, their styles, thicknesses, and spacing conventions. Below, I will explain each type of line and its characteristics as depicted in the image.

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1. CENTER LINE - THIN

- Style: Long dashes with short spaces.
- Thickness: Thin (0.3 mm).
- Purpose: Used to indicate the center of circles, arcs, or symmetrical parts.
- Example:
- Dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{16} \) inch.

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2. SHORT BREAK LINE - THICK

- Style: Short, wavy line.
- Thickness: Thick (0.6 mm).
- Purpose: Used to indicate a break or omission in a part that is too long to fit on the drawing.
- Example:
- Line length: 0.6 mm.

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3. LONG BREAK LINE - THIN

- Style: Alternating long and short dashes.
- Thickness: Thin (0.3 mm).
- Purpose: Used to indicate a break or omission in a part that is too long to fit on the drawing.
- Example:
- Long dash length: 1 inch.
- Short dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{8} \) inch.

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4. DIMENSION & EXTENSION LINE - THIN

- Style: Straight line.
- Thickness: Thin (0.3 mm).
- Purpose: Used to show dimensions and extend from the object to the dimension text.
- Example:
- Line thickness: 0.3 mm.

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5. SECTION LINE - THIN

- Style: Alternating long and short dashes.
- Thickness: Thin (0.3 mm).
- Purpose: Used to indicate the cross-section of an object.
- Example:
- Long dash length: 1 inch.
- Short dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{8} \) inch.

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6. PHANTOM LINE - THIN

- Style: Dotted line.
- Thickness: Thin (0.3 mm).
- Purpose: Used to represent imaginary or alternate positions of parts.
- Example:
- Dot length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{8} \) inch.

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7. STITCH LINE - THIN

- Style: Very short dashes with small spaces.
- Thickness: Thin (0.3 mm).
- Purpose: Used to indicate stitching or riveting.
- Example:
- Dash length: \( \frac{1}{16} \) inch.
- Space length: \( \frac{1}{16} \) inch.

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8. VISIBLE LINE - THICK

- Style: Solid line.
- Thickness: Thick (0.6 mm).
- Purpose: Used to represent visible edges of objects.
- Example:
- Line thickness: 0.6 mm.

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9. HIDDEN LINE - THIN

- Style: Dashed line.
- Thickness: Thin (0.3 mm).
- Purpose: Used to represent hidden edges or features not visible from the current view.
- Example:
- Dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{32} \) inch.

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10. CUTTING PLANE LINE - THICK

- Style: Alternating long and short dashes with arrows at the ends.
- Thickness: Thick (0.6 mm).
- Purpose: Used to indicate the path of a cutting plane through an object.
- Example:
- Long dash length: 1 inch.
- Short dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{32} \) inch.

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11. CUTTING PLANE LINE - THICK

- Style: Alternating long and short dashes with arrows at the ends.
- Thickness: Thick (0.6 mm).
- Purpose: Same as above, but specifically for indicating the cutting plane.
- Example:
- Long dash length: 1 inch.
- Short dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{32} \) inch.

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12. CHAIN LINE - THICK

- Style: Alternating long and short dashes.
- Thickness: Thick (0.6 mm).
- Purpose: Used to indicate the path of motion or travel.
- Example:
- Long dash length: 1 inch.
- Short dash length: \( \frac{1}{8} \) inch.
- Space length: \( \frac{1}{4} \) inch.

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13. SYMMETRY LINE

- Style: Alternating long and short dashes with thick and thin segments.
- Thickness: Thick (0.6 mm) and Thin (0.3 mm).
- Purpose: Used to indicate symmetry in a drawing.
- Example:
- Thick segment length: 0.6 mm.
- Thin segment length: 0.3 mm.
- Space length: \( \frac{1}{16} \) inch.

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Summary

Each line type serves a specific purpose in technical drawings, ensuring clarity and consistency in communication. The chart provides guidelines for the style, thickness, and spacing of these lines, which are crucial for accurate interpretation of engineering drawings.

Final Answer:
\[
\boxed{\text{The image is a line convention chart defining various line styles, thicknesses, and spacings used in technical drawings.}}
\]