When you are trying to choose a bit you will quickly notice that there are many different types to choose from. In addition to different shapes of rings, shanks and mouthpieces that are designed many different ways, horse bits can be made of one, or a combination of different metals, rubber parts or plastic. Each material has its pros and cons. Here is a look at what materials are used to make bits, and why they are used.
Bits can be made of different metals. Most commonly, bits are made of stainless steel . Stainless steel bits may become dull over time, but can be cleaned and polished repeatedly without worrying about ruining the finish. Stainless steel bits are strong and will last a very long time. There's no particular flavor, so most horses won't object to the flavor. Stainless steel takes a long time to warm up, and if you've ever tried to warm up a bit with your hands in the winter before putting it in your horse's mouth, you'll find it takes a very long time.
Bits can also be made of copper, either the whole bit, or just the mouthpiece. Copper is felt to encourage salivation, which is thought to increase the sensitivity of the horses mouth. Because the metal is softer than stainless steel, copper bits wear more quickly although this is countered by mixing in small amounts of other metals. They can also corrode. Copper bits warm up more easily than stainless steel bits. This has to do with the conductivity of the metal, which is why cooks value copper cookware . Some horses may dislike the taste of a copper mouthpiece.
Sweet Iron is made of a mixture of iron and copper. Sweet iron bits look rusty onced 'seasoned', and it is the oxidization that is thought to taste sweet to the horse, and increase salivation. Only bit mouthpieces are made of sweet iron, and cheeks and joints are made most commonly of stainless steel or nickel plate.
Vulcanized rubber and hard plastics are used to encase a thin core of metal on some bits. These bits are generally thicker than many metal bits. Some horses might appreciate the softer feel of a rubber or plastic mouthpiece, while others may find them an uncomfortable mouthful. You might find older plastic or rubber mouthed bits give off a funny smell which your horse might or might not notice. Many plastic mouthed bits are made with a scent thought to encourage the horse to accept the bit more readily. This may encourage some horses to chew the bit and not carry the bit quietly. Both rubber and plastic mouthed bits do wear over time, sometimes quite quickly, leaving rough spots or exposing the metal core. I have heard of riders complaining that their plastic bit broke, although I have not seen this personally. I have a stainless steel pelham with a fracture it, so check any bit you use periodically for cracks, wear or rough spots that could cause problems.
While aluminum is lightweight, easy to maintain and inexpensive, it has a drying effect on the horses mouth. Quite large, ornate bits can be made with aluminum that would be unwieldy made in any other material. However, most horses will dislike the taste of aluminum an aluminum mouthpiece and it can cause the horse's mouth to dry out. This is opposite to the ideal moist, sensitive mouth most riders want, and may actually cause discomfort for the horse.