STEP 2 — ELLIPSES & LINE-WEIGHT

Skill Tree · T0 Instrument Control
3 exercises + Error Analysis

Correct execution Error — what wrong looks like Annotation — frame / intended axis

Step 2

The second and third fundamental marks — the ellipse and the weighted line.

Target two pure-motor skills the whole tree depends on. (1) A confident ellipse drawn through — the basis of every cylinder, wheel, bore, and rounded product form you'll later construct from imagination, and a mark CAD never made you produce by hand. (2) Line-weight control — a deliberate heavy vs. light line in a single pass — the foundation of a line-dominant drawing and of the line-weight hierarchy in later steps. Both are the untrained motor channel. The pencil enters now: line-weight needs pressure modulation a fineliner can't give. Lineage: Drawabox Lesson 1 (ellipses, drawn through) + pen-and-ink line-weight fundamentals (Guptill).

Exercise A · Sessions 1–2 — pen · joins the warm-up

Ghosted ellipses, drawn through

Setup — pen (Micron 03), unruled white paper, ~15 min. No ellipse guide or template.

Procedure — ghost the elliptical motion above the paper 3–4 times, then commit: let the pen travel around the loop 2–3 full times in one continuous motion ("drawing through"), then lift. Work the joint ladder deliberately — a set of small ellipses (coin-size: wrist), a set of medium (fist-size: elbow), a set of large (half-page: shoulder) — and name the engine aloud before each set; the joint's natural arc should match the curve's size. Vary angles and degrees within each set. Mode: motor/mechanical.

Watch & measure — do the 2–3 passes overlap into one tight, smooth shape (not a spiral), with rounded ends and no flat sides — and is the named joint actually driving the motion (no wrist creeping into the large set)?

Correct Smooth and evenly rounded; the draw-through passes sit tightly on each other.

Wrong Points at the ends, flats on the sides = drawn too slowly and steered. Ghost more, then commit faster and let it flow.

Exercise B · Sessions 2–3 — mechanical pencil

Line-weight control

Setup — mechanical pencil (0.5, 2B), white paper, ~15 min.

Procedure — (1) draw a row of parallel lines stepping from lightest to darkest by pressure alone, single pass each; (2) on command, produce a clearly heavy line and a clearly light line, each even end-to-end. Consistent pressure through the whole stroke — never build darkness by scribbling over. (Applying weights to a form — heavy contour, light interior — is deferred to line-weight hierarchy in T5.) Mode: motor/mechanical.

Watch & measure — is each line's weight even along its length (not fading or pulsing)? Is "dark" achieved by pressure in one pass, not by many strokes?

Correct Two weights on command, each even end-to-end — set by pressure in a single pass.

Wrong Darkness faked by stacking many passes. Press in one committed pass, or use softer lead — don't hatch it in.

Exercise C · Sessions 3–4 — pen

Ellipses in a frame

Setup — pen, ~10 min. Freehand a rectangle at varied proportions (or reuse a ghosted plane from Step 1).

Procedure — ghost, then commit an ellipse (drawn through) that kisses all four sides of the rectangle at their midpoints. The frame enforces a symmetric ellipse with an honest minor axis. Mode: motor + first taste of proportion.

Watch & measure — does the ellipse touch all four sides evenly, with its minor axis running straight through the center, not skewed or lopsided?

Correct Touches all four midpoints; minor axis runs straight through the center.

Wrong Not centered on the frame's axes and unequal sides. Check the minor axis against the center cross before committing.

Error analysis

End-of-session checklist

Ellipse pointed at the ends / flat on the sides → drawing too slowly and steering. Ghost more, commit faster, let the shape flow.
Draw-through passes spiral apart instead of overlapping → controlling size by slowing down. Keep the motion quick and tight — shrink the loop, not the speed.
Ellipse lopsided / minor axis skewed → no reference for symmetry. Use the frame (Exercise C) and check the axis through the center.
Line weight fades or pulses along a stroke → inconsistent pressure or wrist-drawing. One pass, consistent pressure, from the elbow.
A dark line built from many scribbled passes → not pressure control. Press in a single committed pass or use softer lead — don't hatch it in.
Reaching for an ellipse template / French curve → CAD-brain. Banned at this stage; the wobble is the data that tells you what to train.

Pass / adjust

Advance or repeat

Advance when both hold
1. Ghosted ellipses come out smooth and evenly rounded — no points or flats — with the draw-through passes tightly overlapped, most attempts.
2. You can produce a clearly heavy and a clearly light line on command, each even along its full length in a single pass.

Repeat if ellipses still point, flatten, or spiral, or line weight pulses or is scribbled in. That means the motor control isn't there yet — smoothness and pressure consistency are the target, not speed of completion. Do not advance on time logged.

Date the pages and keep them with the Step 1 baseline. Add ellipses to the start-of-session warm-up alongside superimposed and ghosted lines — they decay without upkeep too. Next node: T1 perception (contour, gesture, comparative proportion) — the observational track and your least-trained channel, now the priority. T2 construction is also unlocked and will lean hard on these ellipses.