A switchblade (also known as an automatic knife, pushbutton knife, switch, Sprenger, Springer, or, in British English, flick knife) is a type of knife with a folding or sliding blade contained in the handle which is opened automatically by a spring when a button, lever, or switch on the handle or bolster is activated (often confused with a different type of knife, the spring-assist or assisted-opening knife). A manually operated safety device fitted to most switchblades prevents the blade from opening in the event the button is accidentally depressed. Most switchblade designs incorporate a locking blade, in which the blade is locked against closure when the spring extends the blade to the fully opened position. The blade is unlocked by manually operating a mechanism that unlocks the blade and allows it to be folded and locked in the closed position.
The switchblade or automatic knife originated as a response to demands for a gentleman’s knife that could be opened easily with one hand by amputees, the aged, or those who had difficulty opening the traditional folding pocket knife, which normally required the use of both hands. With the advent of mass production, which enabled folding knives to be produced at lower cost, distribution of such knives became much more widespread, with some manufacturers turning out thousands of automatic knives annually. While not as popular as traditional pocket or folding knives, the switchblade enjoyed a devoted if modest continuing popularity as a general utility knife. With the advent of legislation restricting ownership or sale of such knives in the mid-20th century, the worldwide popularity of the automatic knife began to decline. Today most switchblades are largely produced by small knifemaking companies on a semi-custom basis for use by the military or for collectors in countries and states where it is legal to do so.
Early automatic knives
Switchblade knives date from the mid-18th century. Examples of steel automatic folding knives from Sheffield England have crown markings that date to 1840. After the American Civil War (1865), knife production became industrialized. The oldest American made production automatic knife is the Korn Patent knife, with a rocking bolster release. In 1892, George Schrade, a toolmaker and machinist from New York developed and patented the first of several practical automatic knife designs. The following year, Schrade founded the New York Press Button Knife Co. to manufacture his switchblade knife pattern, which had a unique release button mounted in the knife bolster. There Schrade became the company’s production superintendent, establishing a production factory to manufacture several patterns of Schrade-designed switchblade knives, ranging from a large folding hunter to a small pocket knife.
Automatic knives 1900-1945
Italian knifemakers had their own style of knives including both pushbutton and leverlock styles, some bearing design characteristics similar to the early French Châtellerault knife. In the United States, commercial development of the switchblade knife was primarily dominated by the inventions of George Schrade and his New York Press Button Knife Company First patented by Schrade in 1892, most of the company’s knife patterns featured a unique style of clip point blade. In 1903, George Schrade sold all of his interest in the New York Press Button Knife Company to Walden Knife Company, which would go on to sell thousands of copies of Schrade’s bolster button design.
Soon W.R. Case, Union Cutlery, Camillus Cutlery, and other U.S. knife manufacturers were marketing automatic knives of their own design. The advertising campaigns of the day by knife manufacturers such as Schrade focused on marketing the automatic knife to farmers, ranchers, hunters, or outdoorsmen who needed a compact pocket knife that could be quickly brought into action when needed. Schrade’s new Safety Pushbutton Knives were an improved series of switchblade, featuring a handle-mounted operating button and a sliding safety switch. A multi-blade operating button allowed the knife to operate with up to four automatic blades. With the Presto line, Schrade would largely dominate the automatic knife market in the United States for the next forty years. In 1918, Captain Rupert Hughes of the U.S. Army submitted a patent application for a specialized automatic-opening trench knife of his own design, the Hughes Trench Knife. Pressing a button on the handle automatically extended a knife blade into an open position and locked position, allowing the knife to be used as a stabbing weapon. Hughes went on to patent his automatic trench knife in 1919, though Hughes appears to have been unsuccessful in persuading a knife manufacturing company to produce his design.
Under the trademark of Flylock Knife Co., Challenge made several patterns of the flylock switchblade, including a large 5-inch folding hunter model with hinged floating guard and a small pen knife model designed to appeal to women buyers. The line included the KA-BAR Grizzly, KA-BAR Baby Grizzly, and KA-BAR Model 6110 Lever Release knives. On September 21, 1926, George Schrade patented a new switchblade design, the Wire Jack. The knife was made of two pieces of welded wire, a blade, a blade liner, and a rivet. In 1937, Schrade came out with two more low-cost switchblade knives designed to appeal to youth, the Flying Jack and the Pull-Ball Knife. Unfortunately, the Pull-Ball required two hands to open, removing much of the switchblade’s utility as a one-handed knife. As the blade catch mechanism required a good deal of space within the handle, the knife’s blade length was short relative to its handle length. After the war, the M2 was manufactured by Schrade (now Schrade-Walden, Inc.) as the Parachutist’s Snap Blade Knife (MIL-K-10043) under a postwar military contract. Postwar knives and the stilletto switchblade
From the end of World War II until 1958, most U.S.-manufactured switchblades were manufactured by Schrade (now Schrade-Walden, Inc., a division of Imperial Knife Co., and the Colonial Knife Co. Schrade-Walden Inc. made knives under the Schrade-Walden and Edgemaster trademarks, while Colonial made a number of switchblade patterns during the 1950s under the trademark ShurSnap.
The majority of these Italian stiletto switchblade knives used a now-iconic slender bayonet-style blade with a single sabre-ground edge and an opposing false edge. In 1954, the state of New York passed the first law banning the sale or distribution of switchblade knives in hopes of reducing gang violence. In 1957, Senator Estes Kefauver of Tennessee attempted unsuccessfully to pass a law restricting the importation and possession of switchblade knives. Curiously, the sale and possession of stilettos and other offensive knives using fixed or locked folding blades remained legal in most jurisdictions. By the 1960s, new production of switchblades in the United States was largely limited to military contract paratrooper knives. In the 1980s, automatic knives enjoyed a brief spike in sales with the concept of kit knives, allowing the user to insert a spring or build a knife from a parts kit. This loophole for imported switchblade knives was eventually closed by new federal regulations.
Automatic knives today
In Britain, the folding type of switchblade is commonly referred to as a flick knife. While switchblades remain illegal in U.S. interstate commerce since 1958 under the Switchblade Knife Act (15 U.S.C. §§1241-1245), Amendment 1447 to 15 U.S.C. §1244, signed into law as part of the FY2010 Homeland Security Appropriations Bill on October 28, 2009 provides that the Act shall not apply to spring-assist or assisted-opening knives (i.e. knives with closure-biased springs that require physical force applied to the blade to assist in opening the knife). A switchblade opens its blade from the handle automatically with the press of a button, lever, or switch that is remotely mounted in the knife handle or bolster. Today there are still a number of knife companies and custom makers who build high-quality automatic knives for the military, emergency personnel, and knife collectors. Some famous automatic knife manufacturers include Microtech Knives, Benchmade, Severtech, Gerber Legendary Blades, Mikov, Pro-Tech Knives, Dalton, Boker/Magnum, Spyderco, Kershaw Knives, and Piranha. Automatic knife manufacture in Italy consists predominantly as a cottage industry of family-oriented businesses.