EveryCutFileStraight or tapered
| Cup | You measure | The flat wrap |
|---|---|---|
| Straight sides | Diameter D and height H | A rectangle π × D wide and H tall |
| Tapered sides | Top diameter D, bottom diameter d, vertical height H | A curved band. Slant s = √(H² + ((D − d) ÷ 2)²); outer radius R = s × D ÷ (D − d); inner radius r = R − s; angle = 180° × D ÷ R |
A worked example
Our tapered cup wrap example is for a cup 90 mm across the top, 60 mm across the bottom and 100 mm tall. The slant is √(100² + 15²) = 101.1 mm. The outer radius is 101.1 × 90 ÷ 30 = 303.4 mm, the inner radius 303.4 − 101.1 = 202.2 mm, and the band spans 180° × 90 ÷ 303.4 = 53.4°. Laid flat, it measures 272.6 × 122.7 mm. Our straight example, 75 mm across and 110 mm tall, is a 235.6 × 110 mm rectangle.
Measure your cup
- Mark the top and bottom of the area the wrap will cover.
- Measure the outside diameter at both marks with calipers, or wrap a paper strip around, mark where it meets, and divide its length by 3.1416.
- Measure the height straight up between the marks, not along the slope.
- Enter the three numbers in the cup wrap generator, add an overlap if the ends will overlap, and cut a paper test first.
Cups with curved sides
A rounded shoulder, a bulging wall or a handle is outside this model: cover only the straight or evenly tapered part. The overlap is added at the larger rim, and the wrap does not allow for material stretch.
Why there are no cup presets
Two cups sold as 16 oz can differ in diameter and height, and makers rarely publish both. Your own three measurements give the right template.