Contour Line Drawing of a Soda Can: A Focused Study

Object Drawing Lessons

Contour drawing captures the outline and edges of an object without shading or perspective ellipses. This lesson focuses on a soda can as a clear, familiar form. You will use a defined convention: x-height is measured from baseline to midline of lowercase letters, and letter styles vary, so proportions are checked against the actual can rather than a universal template. All resources are planned and free; none are built yet. Work through the sections, avoid common mistakes, and complete the four practice tasks. Each task is self-contained and solvable from the text.

Practice materials: Printable downloads are not available for this lesson yet. Use the instructions and four exercises below.

Reference illustration

Use the stated measurements and conventions for each exercise.

Setting Up and Defining the Contour Convention

Place a clean, empty soda can upright on a flat surface. Use a pencil and paper. Define your drawing area with a light border. The contour convention for this study: draw only visible edges—rim, body sides, base curve, and tab—without shading, label design, or ellipse perspective. Treat the can as a flat silhouette with internal edge lines where surfaces meet. Measure the actual can with a ruler; record height and width in millimeters. Any numerical values in this lesson are hypothetical examples, not standards.

X-height is baseline to midline of lowercase letters. Letter styles vary, so do not assume a fixed x-height for all text. For proportion checks, use the can’s actual height and width. A simple ratio helps: height divided by width. For example, if a hypothetical can is 120 mm tall and 65 mm wide, the ratio is about 1.85. Your can may differ; measure it.

1. Measure the can’s height and width with a ruler; write both in millimeters.
2. Draw a light rectangular frame on paper slightly larger than the can’s silhouette.
3. Mark the top rim line and the base line using the measured height.
4. Mark the left and right body edges using the measured width.
5. Label the tab area with a small box; do not draw the label design.

Blind Contour: Training the Eye and Hand

Blind contour means you look only at the can while drawing, not at the paper. This trains observation of edges. Start at the top rim and move slowly along the outline. Keep the pencil moving at a steady pace. Do not lift the pencil unless the edge breaks. The result may look distorted; that is expected. The goal is to notice rim curvature, body taper, and tab edges.

Use a timer for a short period, such as two minutes. After finishing, compare your blind contour to the can’s actual proportions using the height-to-width ratio. If your drawing’s height is much shorter than the measured ratio suggests, note where your hand sped up. Repeat once with the same can.

1. Place the can where you can see it clearly without turning your head.
2. Put pencil on paper at the top rim; do not look at the paper.
3. Trace the rim edge slowly, then the left body edge, base curve, right body edge, and tab edges.
4. Keep the pencil moving; do not erase.
5. After the timer, look at the paper and compare the overall height and width to your measurements.

Slow Contour: Tracing Rim, Body, and Tab Edges

Slow contour allows glancing at the paper while prioritizing the can’s edges. Draw the rim as a single curved line that follows the visible top edge. The body sides are nearly straight but may taper slightly; follow the actual can. The base curve mirrors the rim’s curvature but is often less pronounced. The tab has small, angular edges; draw them as separate short lines where they meet the can top.

Use the measured height and width to place key points: top rim center, base center, left and right body edges at mid-height. Connect these points with slow, deliberate lines. Check that the tab edges sit within the top rim area. Do not add ellipses or shading. If a line looks wrong, redraw it lightly beside the first rather than erasing heavily.

1. Mark the top rim center and base center using the measured height.
2. Mark left and right body edges at mid-height using the measured width.
3. Draw the rim curve from left to right through the top center mark.
4. Draw the left body edge down to the base, then the base curve, then the right body edge up.
5. Draw the tab edges as short lines inside the top rim area.
6. Compare the finished contour to the can’s height-to-width ratio.

Checking Proportions and Valid Alternatives

Because letter styles vary and x-height is baseline to midline, do not use text on the can as a fixed scale. Instead, use the can’s measured height and width. A valid contour may show the rim as a shallow curve or a deeper curve, depending on the viewing angle. Both can be correct if they match what you see. The rubric allows alternatives: the tab may be drawn with rounded or angular edges if those edges are visible.

Check your drawing by measuring its height and width on paper. Divide height by width. Compare to the can’s ratio. A difference of about 0.1 is acceptable for a freehand study. Also check that the tab edges do not extend beyond the top rim. If they do, adjust the tab lines inward.

1. Measure your drawing’s height and width in millimeters.
2. Compute the drawing’s height-to-width ratio.
3. Compare to the can’s measured ratio; note the difference.
4. Check that the tab edges stay within the top rim area.
5. If needed, redraw one edge lightly to improve the ratio.

Worked example

A hypothetical can measures 120 mm tall and 65 mm wide. Draw a slow contour of its outline, including rim, body, base, and tab edges. Then check the height-to-width ratio.

Four practice exercises

Common mistakes

• Adding shading or label design. Erase or ignore non-contour marks; redraw only visible edges. Keep the label area blank.
• Drawing ellipse perspective on the rim or base. Follow the visible top and bottom edges as curves; do not construct ellipses. Match the can’s actual silhouette.
• Using text x-height as a fixed scale. Measure the can’s height and width with a ruler. Use the height-to-width ratio for checks; letter styles vary.
• Looking at the paper too often during blind contour. Set a short timer and keep your eyes on the can. Accept distortion; the goal is observation, not accuracy.

Self-check rubric

• Contour only: no shading, label design, or ellipse perspective.
• Rim, body sides, base curve, and tab edges are present and follow visible edges.
• Height-to-width ratio of the drawing is within about 0.1 of the can’s measured ratio.
• Tab edges stay within the top rim area.
• Valid alternatives are accepted: rim curve depth and tab edge shape may vary if they match observation.
• Blind contour task shows sustained looking at the can, even if distorted.

Questions and answers