Cotter pins are used as fasteners. Though there are different types of pins, they serve a similar purpose. Some pins, like the hairpin, require bending to be held in place, others have a ring or holding pin, and others are manufactured purposefully to hold themselves in place. Circle cotter pins are available. Clinch pins are made with a loop on one end and are self-securing. Twist pins have a unique locking feature.

Depending on the application, some pins can be reused while others should not. Many pins are made of soft metal which in reusing them, makes them susceptible to breakage. The material from which the types of cotter pins are made should be taken into consideration prior to deciding on a pin for your specific application.

1. Brass cotter pins

2. Stainless steel cotter pins

3. Silicon bronze cotter pins

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Use cotter pin fasteners on vehicles

The automotive and aviation industries require the use of cotter pins to secure various parts of the equipment. Stresses from motion and weather require that special types of strong and non-corrosive pins be used. Even with car racing, pins made from a less durable material need to be used to allow for easy break away of detachable parts.

I recommend: Integrated Publishing discusses the uses of cotter pins with aircraft. At Midwest MasterCraft, see the applications for cotter pins on marine vehicles.

Discover cotter pin fasteners applications and uses with hobbies

Information about cotter pin fasteners is available outside the industrial arena. Many hobbies and recreation options require the use of the pins. Securing appendages on stuffed animals and attaching bodies to frames of model vehicles are only a few of the everyday applications for these securing devices.

I recommend: About.com: Radio Controlled Vehicles explores the use of metric cotter pins with the hobby parts. Metacafe shows how a cotter pin can be used as an aid in fishing.

Use cotter pins safely

Cotter pins have a variety of applications. No matter the application or the industry used in, it is important to use cotter pins carefully in order to avoid damage and injury. Cotter pin misuse can lead to dangerous situations. With a low replacement cost, it is far more beneficial to replace a compromised cotter pin or as a routing replacement than it is to risk a tragedy.

I recommend: Sizes explores the correct use of cotter pin types for optimum safety. The DOOTalk forum explores the possibilities of a cotter pin fastener breaking.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  If you are unsure, your supplier of cotter pin fasteners is the best asset you have in determining the most appropriate type of cotter pin and which is the best material cotter pin to use.

Made of wire, a cotter pin is a two-tined metal fastener that is used in everything from stock cars to wagons. Suppliers of cotter pins usually offer the fasteners in either standard or metric sizes, so be sure you know what you're looking at before you order. Special brass cotter pins are usually purchased by furniture manufacturers to hold drawer pulls. Because they are made of brass, they are more expensive than wire cotter pins.

Whether you're looking to buy brass cotter pins or another metal type, be sure what you're getting is new and in good condition since bent parts can make cotter pins useless.

Consider which of the following you'll need for the easiest cotter pin installation:

1. Ready-made or custom cotter pin fasteners

2. Cotter pins in metric sizes

3. Cotter pin tools

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Shop the widest variety of cotter pin prices online

You can find cotter pins, like many other fasteners, anywhere from your local hardware store to specialty parts stores. You can also find them easily, and possibly at their cheapest, online. And, unless you need custom cotter pins made for a specific application, you can even buy them bulk or in assortment kits.

I recommend: Pivot Point and NutsandBolts.com offer a wide variety of cotter pins in standard sizes. If you need custom-made cotter pins, send a sketch or blueprint to Western Wire Products Co..

Find metric cotter pins sold in sets or through companies dedicated to metric sizes

Cotter pins are available in both standard and metric sizes. If you're looking for metric cotter pins, you can find online manufacturers, but make sure the company complies with International Standard Organization (ISO) requirements. This will ensure that you get what you ask for the first time.

I recommend: Fuller Metric Parts, Ltd., is ISO 9001:2000 certified and specializes in metric cotter pins and fasteners. Buy cotter pin fasteners in an assortment of 880 metric cotter pins at BikeBandit.com.

Be sure to get the right tools for cotter pin fasteners

The different types of cotter pins and sizes vary, but no doubt there are a couple of types of tools you'll likely need when working with cotter pins. Cotter pins are, after all, fasteners which means their job is to hold two things together. It also means that taking out an improperly installed cotter pin can be a pain without the right tools.

I recommend: Find inexpensive cotter pin accessories through both The Tool Warehouse and General Tools and Instruments. Buy tools for industrial applications and the railroad industry at Ajax Tools.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Many manufacturers suggest using the largest cotter pin fastener to fit the hole to prevent slippage. This can prevent many injuries, especially important when cotter pin fasteners attach wheels to toys and bicycles.

Cotter pin fasteners come in a many sizes and types. Cotter pins, also called split pins, have two legs, or tines, that split or spread to keep them from moving out of position. Engineers, designers, and mechanics use cotter pins to hold other fasteners in place. The pins are easy to install and remove, facilitating repairs and maintenance. Cotter pins are relatively inexpensive and provide safety when holding a pin, nut, or other fastener in place is essential.

Many types of cotter pins are available, as are suppliers of cotter pins. Information about cotter pin fasteners for beginners is readily accessible from a manufacturer of cotter pin fasteners or from government pamphlets, such as those published by the Federal Aviation Administration (FAA). Information about cotter pin fasteners will include answers to the following questions:

1. For what can you use cotter pins?

2. How and why do cotter pin types differ?

3. Where can you find cotter pins, and what are the prices?

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Discover the many uses of cotter pins

Manufacturers make cotter pins from many different materials, such as steel, stainless steel, copper, and brass. Cotter pins are used in machinery of all kinds, but particularly in aviation and marine applications for ensuring safety. A cotter pin's main job is to ensure that other components of a machine stay in place.

I recommend: You can find a good basic discussion of the many uses for cotter pins on Sizes, along with a table of sizes and other helpful information, but you must register to have access to everything. Jamestown Distributors, a supplier of cotter pin fasteners, displays a good list of American standard sizes for marine use, with prices per box.

Learn how to select the correct cotter pin fasteners

Selecting the correct cotter pin involves getting the right size and the right material. Manufacturers of cotter pins size by fractions of an inch. Keep in mind that some applications call for metric cotter pins. Where corrosion is a problem, you may be required to use stainless steel or brass cotter pins.

I recommend: Northeast Fastener Co. provides a short video on how to correctly measure a cotter pin and gives information on how to buy cotter pin fasteners. Zycon Global Services shows a good assortment of pins with different shapes and materials and lists metric sizes. The illustrations include pins designed to meet military standards.

Find the correct methods of installing cotter pin fasteners

Correctly installing a cotter pin to hold another pin in place involves inserting the pin and spreading the two tines. However, if you use the cotter pin to hold a nut or other retainer in position to maintain correct tolerance, the installation becomes a bit more complex. Aviation manuals provide some of the best instruction on proper methods of installation.

I recommend: Integrated Publishing shows the proper method of bending a cotter pin fastener so that it will safely secure a nut or a pin to meet aviation standards. Sport Truck provides pictures of cotter pins during installation on an engine.