15mm Spiral Binding Coils

The stated capacity is a useful reference for plain 20 lb paper, not a universal limit for every document. Tabs, poly covers, cardstock dividers, laminated sheets, and coated paper all add thickness faster than standard sheets. A document with fewer sheets can therefore need the same coil diameter as a much longer plain paper report. Assemble the actual materials and measure the stack at the binding edge before ordering. The pages should turn smoothly and fold back without pulling the punched holes toward the coil. When the fit is borderline, a slightly larger diameter usually produces a cleaner and more durable result. Avoid removing important covers or dividers only to meet a nominal sheet figure, since the finished function matters more than the count.

Choose a color that supports identification and remains consistent across future production. Some organizations assign colors by department, document type, revision cycle, or client, while others match the cover or printed branding. The range of spiral coil colors makes it possible to keep the same diameter and pitch while changing the visual coding. Consider how the coil looks against both the front and back cover, especially when one cover is transparent. Dark colors can create a defined spine, while clear or neutral tones keep attention on the printed design. Record the selected color with the pitch, diameter, and length so repeat orders remain consistent and supplies are not mixed accidentally.

A 15mm coil can be inserted by hand for occasional work. Begin by turning the first few loops through the punched holes, then continue rotating the coil while keeping the document edge aligned. A manual method becomes slower and less consistent as document volume increases, especially with thicker stacks that require more control. An electric inserter speeds the threading step, but it does not replace accurate punching, proper coil sizing, or final crimping. Production volume should guide the equipment decision. A few documents at a time may not justify an inserter, while repeated runs can benefit from faster and more even threading. In either case, use a sample document to confirm that the coil moves freely through every hole before processing the full batch.

Cutting removes the excess length, and crimping forms a stop that prevents the coil from rotating out of the document. Both ends should be finished after the coil passes through every hole. The spiral coil accessories include tools intended for clean trimming and secure end formation. Leave enough coil beyond the final holes to create a complete crimp, usually about half to one and a half loops, then bend the flattened ends toward the binding edge. Long untrimmed ends can snag, while short or incomplete crimps may slip back through the holes. After finishing, rotate the document and gently test both ends. A properly crimped coil remains secure while still allowing easy sheet movement.