A spiral binding consists of a continuous wire, which is coiled through evenly spaced holes that have been punched into the pages of a book. The spiral wire can be made
of metal, plastic, or plastic coated metal. Plastic is available in a variety
of colors, but the metal spiral has a limited color selection. When the books
are open, the pages lie flat. The pages can also be folded over completely,
which makes spiral binding a good choice for training manuals, cookbooks, notebooks,
and calendars.
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Diameter Guide for Spiral Binding
The examples below are based on booklets consisting of
20 lb. bond pages with heavy weight covers on the front and back.
|
Number of sheets
|
Approx. thickness including covers
|
Coil diameter
|
30 (60 pages)
|
1/8"
|
6 mm
|
40 (80 pages)
|
5/32"
|
7 mm
|
50 (100 pages)
|
3/16"
|
8 mm
|
60 (120 pages)
|
7/32"
|
9 mm
|
70 (140 pages)
|
9/32"
|
10 mm
|
80 (160 pages)
|
5/16"
|
11 mm
|
90 (180 pages)
|
11/32"
|
12 mm
|
100 (200 pages)
|
3/8"
|
13 mm
|
110 (220 pages)
|
7/16"
|
14 mm
|
125 (250 pages)
|
1/2"
|
16 mm
|
140 (280 pages)
|
9/16"
|
18 mm
|
160 (320 pages)
|
5/8"
|
20 mm
|
180 (360 pages)
|
11/16"
|
22 mm
|
210 (420 pages)
|
13/16"
|
25 mm
|
230 (460 pages)
|
15/16"
|
28 mm
|
250 (500 pages)
|
1"
|
30 mm
|
265 (530 pages)
|
1-1/16"
|
32 mm
|
|