Our spiral diameter is measured by inside dimension. Rule of thumb; Book thickness + 1/8” = inside diameter. Please note, 3/16”+ may need to be added for larger books.
Binding edge plus one (1) inch. This lets you cut and turn, and also helps to avoid “running through and backing up.”
Pitch or holes per inch
Start with a ruler at the edge of the first hole, and count to the inch mark. This will give you an indication of how many holes per inch. If you are not sure on the pitch, provide a punched sheet to help us determine correct holes per inch.
PEL spiral coils come in seven different pitches; in various diameters, gauges, colors, materials and lengths. Let our 85 years of experience work for you.