How to Determine 30cm in a Right-Angle Turn?

[Turner]

In a left right-angle turn, align the highest point of the wiper blade/notch/'7' shaped groove with the right lane line, drive a short distance, then check the right rearview mirror—once the car body is straight, you're good. Right-angle turns can also be to the right. For right right-angle turns, use the raised root of the left wiper blade or the air vent as reference points.

[DeEverly]

I've been driving a taxi for over a decade, and maintaining a precise 30cm distance when taking sharp right-angle turns is a delicate skill. My method involves using the wheels and roadside as visual references: during the turn, I focus on the right-side rearview mirror, and when I see the wheel edge just covering the boundary of the roadside line, that's usually the 30cm mark. However, this depends on the vehicle size and mirror adjustment – with my old sedan, raising the mirror slightly gives better accuracy. The key is practice: before each shift, I'd draw chalk or tape lines in the parking lot to simulate curbs, slowly approaching while visually calibrating and counting steps. That 30cm standard is crucial for avoiding scrapes, especially in urban hutongs. Always reduce speed – never rush, particularly in rain when visibility worsens and misjudgments happen. I always advise new drivers to practice with cardboard boxes as reference markers in empty lots to develop muscle memory.

[LorenzoFitz]

As a commuter who drives to work every day, I find it quite important to accurately gauge the 30cm distance when making right-angle turns. I use the simplest method: have a friend stand 30cm away from the curb, sit in the driver's seat, and observe the rearview mirror to memorize the reference point—for example, when the friend's shoulder is exactly halfway framed by the mirror. When turning, I mentally align this reference point with roadside objects like flower beds or utility poles. Once aligned, the distance is good. However, this method is affected by seat height, so SUVs require recalibration. I've tried using mobile apps or parking sensors for assistance, but they're unreliable—parking sensors have delays and false alarms. Periodically measuring the actual distance with a tape measure in the garage helps build a visual database. Safety-wise, maintaining 30cm prevents hitting pedestrians' legs or scraping the underside of the car. With practice, the body gradually develops muscle memory.

[GiannaLee]

As a stay-at-home mom, I always encounter right-angle turns in the residential area when driving my kids around. For judging the 30cm distance, I rely entirely on the left rearview mirror. When turning left, I watch the mirror to ensure there's a small gap between the position where the curb appears in the mirror and the edge of the wheel—that's roughly 30cm. On narrow roads, I make slight adjustments to the steering wheel position to prevent the front of the car from getting too close. My small car has a high seat, which makes observation easier, but when I first tried it, I measured the distance with a tape measure in an open area and marked a reference point—this made turning much smoother. Keeping 30cm prevents the curb from scraping the tires and avoids pedestrians getting too close. During my early days as a new driver, I often learned the hard way from scratches.