Split Pins (Split Cotter Pins)
We can offer a range of split cotter pins in many diameters, lengths and materials. A majority of our “OBSOLETE STOCK” is MILD STEEL, although we do have a small limited number in both BRASS and A2 STAINLESS STEEL.
If when you enquire we can only offer a longer size, do not be put off as you can cut them down to suit. Also, we are usually able to source non stocked items from our wide and varying range of trusted suppliers.
Diameters on offer are usually listed in imperial (inch) sizes and these are shown with the metric equivalent in brackets.
1/32” (0.8mm), 3/64” (1.2mm), 1/16” (1.6mm), 5/64” (2.0mm), 3/32” (2.4mm), 7/64” (2.8mm), 1/82 (3.2mm), 9/64” (3.6mm), 5/32” (4.0mm), 3/16” (5.0mm), 7/32” (5.6mm), ¼” (6.0mm), 5/16” (8.0mm), 3/8” (10.0mm), ½” (12.0mm), 5/8” (16.0mm).
Lengths range from ½” (12mm) – 5” (125mm)
Nowadays some split cotter pins are measured only in millimetres.
What Are Split Pins?
A split pin, also known in the United States as a cotter pin or cotter key is a metal fastener with two tines that are bent during installation. Typically made of thick wire with a half-circular cross-section. The British definition of a cotter pin is equivalent to the US term cotter. To avoid confusion, the term split cotter is sometimes used for a split pin.
A new split pin has its flat inner surfaces touching for most of its length so that it appears to be a split cylinder. Once inserted, the two ends of the pin are bent apart, locking it in place. When they are removed they are supposed to be discarded and replaced, because of fatigue from bending.
Split pins are typically made of soft metal, making them easy to install and remove, but also making it inadvisable to use them to resist strong shear forces.
Measure a split cotter pin as shown; the diameter x the length of the short leg from under the head.