Learn straight rail: turn one point into a controlled run.

Start with contact thickness and speed

Contact thickness determines how much forward speed is transferred to the first object ball and which line the cue ball follows. A full hit transfers more speed; a thin hit lets the cue ball retain more of its travel.

Practise without side spin first. Set up three simple positions and play the same carom at three speeds. Do not record only whether it scored. Observe where every ball stopped; that is the foundation for predictable draw, follow and side spin.

• Full contact: high transfer to ball one and less cue-ball travel.
• Half-ball contact: a useful reference for direction and dosage.
• Thin contact: low transfer and greater cue-ball travel.
• Quiet speed: shorter travel and usually easier gathering.

What spin does

Contacting above centre produces forward rotation and helps the cue ball continue after ball one. Contacting below centre produces backspin; if enough remains after collision, the cue ball draws back. A centre-area hit at the correct speed can create a stop or stun response.

Side spin mainly changes cushion behaviour and can subtly change ball-ball contact through throw. Use it to open or close an arrival angle, not to disguise an incorrect contact thickness.

When does spin die?

Spin has no single off switch. Cloth friction acts while the ball slides, changing draw or follow toward natural roll. Once the cue ball rolls without sliding, visible draw or follow relative to its travel has largely become normal rolling motion.

Side spin rotates around the vertical axis and decays differently, often more slowly. It may remain after forward motion has reached natural roll. A cushion then exchanges speed and spin again, lengthening or shortening the rebound. Distance, pace, cloth, heat and ball condition all affect how much spin remains.

Gathering and reducing the position

Gathering means bringing all three balls into a compact, useful position after the carom. Do not simply drive everything toward one spot. Control ball one, deliver the cue ball toward ball two and use ball two as a brake or return point.

When direct gathering is too risky, reduce the position in stages. Shorten the distances first and build the compact run later. This avoids a hard all-or-nothing recovery stroke.

• Decide which ball should move least.
• Control ball one with contact thickness, not cue force alone.
• Bring the cue ball to the inside of the next position.
• Prefer three manageable balls over one spectacular point.

Return shots and rappels

A return shot sends an object ball through one or more cushions back toward the area where the other two balls meet. Correct contact thickness and speed are inseparable: too full leaves it short; too thin sends it beyond the gathering zone.

Train from fixed positions and judge the exercise by the finishing zone, not only the carom. When both object balls finish within a hand's width of the cue ball, the shot served its positional purpose.

Recognizable straight-rail patterns

The most famous run pattern is the rail nurse, also called the Série Américaine. The balls form a compact triangle near the cushion and move along it through small repeatable contacts. Contact thickness, soft pace and the changing roles of both object balls must be exact.

Other recurring families include small drive shots, follow gathers, draw gathers and short- or long-cushion returns. Learn the purpose behind each family: hold, exchange, return or leave a corner zone in time.

A twenty-minute practice block

Record more than your high run. Count how many strokes produced a usable next position. That second number says more about your development.

• 5 minutes: the same half-ball carom without side spin at three speeds.
• 5 minutes: stop, follow and draw from the same line.
• 5 minutes: return one object ball through the short cushion toward the other two.
• 5 minutes: make a five-point run without allowing any ball to travel more than half the table.

Sources and verification

Content last verified on 8 August 2026. In official competition, the current governing rulebook takes precedence.

• USBA — straight rail, gather shots and rail nurse
• Mathavan, Jackson & Parkin — physics of ball-cushion impact (PDF)
• Erik Kiefl — sliding, rolling, spin and collisions
• KNBB — concise billiards rules (PDF, Dutch)