Interchangeable parts are components of any device designed to specifications which insure that they will fit within any device of the same type. This streamlines the manufacturing process, since all pieces are guaranteed to fit with all others, and it similarly creates the opportunity for replacement parts.

Prior to the 18th century, devices such as guns were made one at a time by gunsmiths, and each gun was unique. If one single component of a weapon needed a replacement, the entire weapon either had to be sent back to an expert gunsmith to make custom repairs or discarded and replaced by another weapon. A gunsmith is a person who designs, builds, repairs or modifies firearms to blueprint and customer specifications, using hand tools and machine tools such as grinders and lathes. ...

Around 1778, Honoré Blanc began producing some of the first firearms with interchangeable parts. Blanc demonstrated in front of a committee of scientists that his muskets could be assembled from a pile of parts selected at random. Other inventors to implement the principle included Henry Maudslay, John Hall, and Simeon North. Honoré Blanc was a French gunsmith and a pioneer of the use interchangeable parts. ... Henry Maudslay. ... John Hall was the inventor of the the most successful breech-loading flintlock rifle of the 19th century. ... Simeon North (1763 - 1852) was a Middletown, Connecticut gun manufacturer, who developed Americas first milling machine in 1818. ...

In the U.S., Eli Whitney saw the potential benefit of developing "interchangeable parts" for the firearms of the United States military, and thus, around 1798, he built ten guns, all containing the same exact parts and mechanisms, and disassembled them before the United States Congress. He placed the parts in a large mixed pile and, with help, reassembled all of the weapons right in front of Congress, much like Blanc had done some years before. Eli Whitney Eli Whitney (b. ... Year 1798 (MDCCXCVIII) was a common year starting on Monday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Friday of the 11-day slower Julian calendar). ... Congress in Joint Session. ...

The Congress was immensely impressed and ordered a standard for all United States equipment. With interchangeable parts, the problems that had plagued the era of unique weapons and equipment passed, and if one mechanism in a weapon failed, a new piece could be ordered and the weapon would not have to be discarded.

The principle of interchangeable parts quickly made mass production in all sorts of industries relatively easy. It was based on the use of templates, applied by semi-skilled labor using machine tools instead of the traditional hand tools. With the introduction of the assembly line at the beginning of the 20th century, interchangeable parts became ubiquitous elements of manufacturing. Mass production is the production of large amounts of standardised products on production lines. ... A machine tool is a powered mechanical device, typically used to fabricate metal components of machines by machining, which is the selective removal of metal. ... A hand tool is a device for doing a particular job that does not use a motor, but is powered solely by the person using it. ... Modern car assembly line. ... -1...

See also

• Preferred numbers

In industrial design, product developers must choose numerous lengths, distances, diameters, volumes, and other characteristic quantities. ...

External links

• Origins of interchangeable parts