A screw is a fastener that has a ridge or thread encircling the entire length of the device, while a bolt has a smooth shaft and a threaded end. Screws have heads with a depression indicating the type of driver necessary for fastening. Bolt heads are manipulated with a wrench and often have hexagonal designs.Continue Reading
Screws and bolts are fasteners used for various types of construction and repair. They have different heads and body designs that make each of them uniquely appropriate for certain projects. The specification allows for ease of assembly and greater durability of final products.
A screw is an externally threaded post that bears ridges all the way down the length of the shaft. This threading helps dig into the surface of the pieces being screwed together, making it difficult to pull the materials apart and providing greater support in solid objects. Screws are perfect for drywall and wood.
A bolt is a smooth length of metal with a substantial head and a threaded tip. It is paired with a nut on the end that is fastened to the threading and provides reinforcement while also permitting materials to expand and contract without creating as much friction. Bolts are ideal for metal structures.Learn more about Tools
Bolt Depot lists nine standard machine screw sizes, the smallest of which is seven-sixty-fourths of an inch with a thread count of 40, while the largest is three-eighths of an inch with a thread count of 16. Some machine screws share the same diameter but feature differing thread counts.Full Answer >
A metric screw and bolt thread chart can be found at FastenerMart.com. Unlike inch-sized screws and bolts, metric screw sizes are preceded by an "M," and the dimensions are listed in metric units.Full Answer >
Pitch circle diameter is a term used to describe the centerline diameter of a circular bolt spacing, the diameter of theoretical friction discs that would transmit the same velocity ratio as two meshing gears, or the diameter at which the thread tooth equals the thread spacing for screw threads. Context should be used to determine whether the term is being used to describe bolt spacing, gears or threads.Full Answer >
The most important specification to consider when buying flat washers is their size, which determines whether they appropriately fit the specific thickness and length of a bolt onto which they’re placed. Other important specifications include the type, form and the intended application.Full Answer >