subject: The Art Of Simple Machines [print this page] Meant for fastening and assembling parts securely, bolts and nuts fall under the group of simple machines. Simple machines are devices having just a few or no moving parts at all that overcome resistance and double or even triple force exerted. Stated simply, simple machines make work easier.
Simple machines consist of levers, pulleys, inclined planes, wheels and axles, wedges and screws. In the case of zinc carriage bolts, these are screws. They are also called coach bolts or plow bolts in certain countries. Fundamentally, a screw is a cylinder that has a flattened top with ridges running through it. It consists of the head found on one end of the screw that allows it to be turned and the shank which is the cylindrical end of the screw that can be threaded fully or partially.
With zinc plated bolts, the head is dome shaped. In technical terms, zinc carriage bolts have countersunk heads and are not meant to be driven. Right under the head, its shank is topped with a short square segment. A nut is fixed at the end of a bolt to increase its power of holding things together and locks the zinc carriage bolt in its place. When inserted through holes of the parts to be assembled, the short square section under the head holds onto the part being affixed to keep the bolt from twisting or turning when the nut is being tightened. Other bolts have ribbing that take the place of the square part under the head.
Zinc carriage bolts are commonly used to put wooden pieces together. It can also be used for wood to metal applications. Thus, the square under the head pulls into the wood as the nut is tightened for a tighter fit. The ribbing has the same function and works better if used for putting together wood and metal components. For things that come in contact with the elements like in building decks, docks, or swing sets or are in places near corrosive chemicals, these bolts are ideal. Zinc carriage bolts are bolts whose steel is plated with zinc to provide moderate protection from rust and corrosion.
They are available in a variety of diameters that range from 3/16 to 1/2. The right width and diameter of the bolts have to be used in assembling pieces together. If the plated zinc bolts are too big, it can put too much pressure on the wood or metal and in turn may cause it to crack and break. If they are too small, the zinc carriage bolts and fastenings may break. The bolts must be of the right length too. They are usually used for thick pieces of wood and if it is too short, it cannot go through the materials that are being put together. On the other hand, if it is too long, the protruding parts are eye sores and may be the cause injury. Always ask the advice of your construction equipment dealer to be sure of the carriage bolt specifications you need.
