Slot car
From Wikipedia, the free encyclopedia
"Slot Car" is a generic term used to describe a powered model or toy vehicle that runs on a preformed track using some form of guide fitted to the vehicle which enables it to follow the track.
The term first came into use in the late 1950s to differentiate between independantly controlled electrically powered model cars that ran on raised rails "rail racing" and those that ran in sunken groove or slot "slot racing" [1] [2]
Generally the slot car is guided by a groove or a slot in the track on which it runs and a pin or blade extends from the bottom of the car into the slot.
Commercially produced Slot cars are usually designed to look like scale models of real automobiles, but equally in the hands of some enthusiasts, the precise relationship with an automobile can be very tentative.
The terms "Slot Car" and "Slot Racing" are loosely interchangeable and as such have been used to encompass other types of model vehicle - motorcycles[3], boats[4] , aeroplanes[5] , spacecraft[6], horses[7], trucks etc. running on similar purpose built tracks. These terms have also been used to describe commercially produced diesel powered model cars and model cars running on a track where there is no independent control other than an on/off switch underneath the model.[8]
Most enthusiasts use commercially-available slot cars (often modified for better performance), others motorize static models, and some "scratch-build," creating their own mechanisms and bodies from basic parts and materials. A few racers custom-design their cars' bodies and chassis.
Though some slot cars are used to model highway traffic on scenic layouts, the great majority are used in the competitive hobby of miniature motor-racing, also called slot car racing or slot racing.
Racers generally use a hand-held controller or throttle to regulate a small electric motor hidden within each car; greater pressure on the throttle produces a greater speed. Each car runs on a separate lane, with its own guide-slot. The challenge in racing slot cars comes in taking curves at the highest speed that will not cause the car to lose its grip and spin sideways, or 'deslot' and leave the track altogether. As in actual rear wheel-drive auto racing, some "drift" of the back end of the car is possible (even though it offers no comparable advantage), and this adds a touch of realism to slot racing.
Though many slot car racers prefer a racetrack unobstructed by scenery, some enthusiasts, much as in model railroading, build elaborate tracks, sculpted to have the appearance of a real-life racecourse, including miniature buildings, trees and people. Slot car racing has a smaller (though no less enthusiastic) following than model railroading.
Contents |
[edit] How it works
Left is a schematic diagram of the wiring of typical 1:24 and 1:32 scale slot car setups. The track is part of a circuit, and the voltage is varied by a resistor in the hand controller. Power for the car's motor is carried by metal strips next to the slot, and is picked up by contacts alongside the guide flag (a swiveling blade) under the front of the slot car.
HO slot cars work on a similar principle, but the electrical contacts, called "pickup shoes," are generally fixed directly to the car's chassis, and a round guide pin is sometimes used instead of a swiveling flag. The current is carried by thin metal rails which project barely above the track surface.
Today, in all scales, 'downforce' or 'traction' magnets are often used to help hold the car to the track at higher speeds, though some enthusiasts believe magnet-free racing provides greater driving challenge and enjoyment.
[edit] Common slot car scales
There are three common slotcar scales (sizes): 1:24 scale, 1:32 scale, and so-called HO scale (1:87 to 1:64 scale). These are also commonly written as 1/24, 1/32, 1/87 and 1/64. Usual pronunciation is "one twenty-fourth," "one thirty-second," and so on, but sometimes "one to twenty-four," "one to thirty-two," etc.
- 1:24 scale cars are built so that 1 unit of length (such as an inch or millimeter) on the model equals 24 units on the actual car. Thus, a model of a Jaguar XK-E (185" or 4.7 m overall length) would be 7.7" long (19.6 cm) in 1:24 scale. 1:24 cars require a course so large as to be impractical for many home enthusiasts, so most serious 1:24 racing is done at commercial or club tracks.
- 1:32 scale cars are smaller and more suited to home-sized race courses but they are also widely raced on commercial tracks, in hobbyshops or in clubs. This scale is the most popular in Europe. Our Jaguar XK-E would be about 5.8" (14.7 cm) in 1:32 scale.
- HO-sized cars vary in scale. The original small slot cars of the early 1960s were intended to function as accessories for model trains, either American/European HO scale (1:87) or British OO-scale (1:76), and roughly approximated those sizes. As racing in this size evolved, the cars were enlarged to take more powerful motors, and today they are closer to 1:64 in scale; but they still run on track of approximately the same width, and are generically referred to as HO slot cars (OO in Britain). They are not always accurate scale models, since the proportions of the tiny bodies must often be stretched to accommodate a standard motor and mechanism. The E-Jaguar scales out to 2.1" (5.3 cm) in 1:87 and 2.9" (7.3 cm) in 1:64. Though there is HO racing on commercial and shop-tracks, probably most HO racing occurs on home racetracks.
In addition to the major scales, slot cars have been commercially produced in 1:48 and 1:43 scale, corresponding to O-gauge model trains. 1:48 cars were promoted briefly in the 1960s, and 1:43 slot car sets are generally marketed today (2006) as children's toys. So far, there is little organized competition in 1:43, but the scale is gaining some acceptance among adult hobbyists for its affordability and moderate space requirements. The E-Jag would be 4.3" (10.9 cm) in 1:43.
[edit] Slotless and digital racing
In the mid and late 1970s several manufacturers came out with primitive slotless racing systems that theoretically allowed cars to pass one another from the same lane. Most worked on a system of multiple rails that allowed one car to speed up momentarily and move to the outside to pass. Though briefly successful as toy products, none of these systems worked well enough to be taken up by serious hobbyists.
In 2004, a number of traditional slot car manufacturers introduced Digital Slot Racing to the market. Digital slot racing promises to fundamentally change the way in which circuits are constructed and in which races are held, making them much more like real life. Multiple cars can now race on one lane, and change lanes to overtake.
[edit] Slot racing organizations
HO Organizations
There are two large HO racing organizations in the US: HOPRA and UFHORA. Each hosts a national competition annually, usually in July. There are many state-wide organizations running under HOPRA and/or UFHORA rule sets.
The Fray In Ferndale boasts the largest turnout of any slot car race in the world, where the best show up to compete for top honors. The highly competitive race is held yearly, in February, and more than 100 individuals, and 16 teams, show up to race on 8 tables. This is the race that determines the direction that the hobby takes, regarding the venerable Aurora Thunderjet. The race has been held since 1997.
Unlike 1:24 scale tracks, HO race tracks can be small enough to fit in common basements. As such, most state organizations run some, if not most, of their series on home tracks as opposed to hobby shop tracks. Additionally, home tracks are often used for national competition.
1:24 scale racing organizations
There are many different local, regional, national, and international organizations for 1:24 scale slot cars. 1:24 scale is primarilarily raced at commercial slot car raceways. The largest USA organisation, holding 2 Divisional USA National Championship events every year, is the USRA, United Slot Racers Association.
The 2006 Division 1 (Wing) Nationals (or "Nats") were held at Chicagoland Raceway in the Chicago suburb of LaGrange July 27th to August 6th. All races were run on the Mike Swiss designed and built American Raceways "Blue King" replica.
2006 Wing Car USA Nats Champions:
Am Spec-15: James Grinstead (SoCal)
Am Box-12: James Grinstead (SoCal)
Expert Box-12: Brad Friesner (Canada)
Am International 15: David Key (Texas)
Expert International 15: Joe "Chubby" Salzman (NY)
Am Cobalt-12: Ed Gibson (Kentucky)
Expert Cobalt-12: Paul "Beuf" Pederson (Idaho)
G7 Warm Up: Bob Everett (Washington)
Geezer Group 7: Vlado Okali (Czech Republic)
Am Gp 27:Earl Simpson (Georgia)
Expert Gp 27: Louis "Gugu" Bernadino (Brazil)
Semi-Pro Group 7: Terry Kunz (Texas)
Pro Group 7: Paul "Beuf" Pederson (Idaho)
The 2006 Division 2 (Scale) Nationals were held at Slot Car Raceway in Rohnert Park, CA starting on April 18 and concluding on April 23rd.
2006 Scale Nats Champions:
1:32 Eurosport - Paul Gawronski
AM GT-12 - Zac Grinstead
Expert GT-12 - Herman James
C-12 Eurosport - Paul Gawronski
Am GTP - Chris Rodriguez, Jr.
Expert GTP - Duran Trujillo
Am GT1 - Ron Southern
Expert GT1 - Paul Gawronski
Jr Group 10 NASCAR - Zac Grinstead
Am Group 10 NASCAR - Zac Grinstead
Expert 4.5 NASCAR - Duran Trujillo
Expert Group 10 NASCAR - Duran Trujillo
Am 4.5 NASCAR - Bill Vanderziel
The President of the USRA, Chris Radisich, is considering sanctioning a "Division 3" which will be for vintage-type or retro slot racing cars. The rules and Division 3 series are at this moment still evolving, but the purpose is to create a class where the cars raced are easily recognized and to shift away from expensive high tech componentry.
The 25th World Slot Car Championship (aka "The Worlds") was held May 17-21 2006 in Rio De Janeiro, Brazil at Top Slot Raceways. It was sanctioned by the NPRA which is a South American slot racing federation.
2006 Worlds Champions:
Group 7 (open) - Joao Carlos Geraldo
1:32 scale racing organizations
In 2004, the True Scale Racing Federation was established by former pro 1:24 racer Phillipe de Lespinay (aka: PdL) with the goal being to establish a north American "true scale" 1:24 and 1:32 North American racing series. The TSRF concept is very similar to full-scale "spec" racing where only TSRF approved equipment can be used for competition. Although the TSRF-legal equipment has been available for some time, the racing series is still in its genesis, having mostly run points-races in the Buena Park, CA area. It is important to note that the TSRF racing series has attracted "name" racers such as Mike Steube, Paul Sterrett, and Mike Aguirre (see "USRA Division 3" above).
[edit] Competition tracks
Competition tracks are most often laid out as road courses with many turns, though ovals and "tank tread" (trapezoidal) ovals are also fairly common. Some competitors also enjoy slot car drag racing on a long straight strip of track. On a road course or oval, each car and each lane is generally marked with "lane tape" of a distinguishing color, allowing the corner marshals (officials) to return cars that have spun off the track to the proper lane.
Generally, tracks for formal competition may have banked corners and may bridge one section over another, but may not otherwise use "trick" configurations. Home tracks often include special features to increase the drama and/or challenge of racing, such as slots that wiggle or squeeze the lanes together, bumps, airborne jumps, or uneven surfaces, but these are typically called "toy" tracks and are not used for competition in more serious organizations.
The controllers (throttles) are usually hand-held and attached by wires to the driver's station. Originally controllers contained only a variable resistor, so separate controllers with different resistance ranges were required for the various classes of cars. Modern electronic controllers have a sensitivity adjustment, and can be used for all classes. Additionally, modern controllers usually feature an adjustable "brake", "coast", and "dial-out". Braking works by temporarily connecting the rails via a resistor; this converts the car's motor into a generator, and the magnetic forces that turned the motor are now slowing it down. Coast allows a certain amount of power to continue to the track after the driver has "let-off" (which would normally cut all power to the car). A dial-out allows the driver to limit the maximum power that can reach the car. Modern controllers usually require three connections - one to the power terminal of the driver's station (customarily white), one to the brake terminal (red), and one to the track terminal (black).
Tracks are wired in one of two ways: with the power terminal connected to the power source positive and the brake terminal negative (called "positive gate"), or the other way around ("negative gate"). To avoid damage, modern controllers feature a switch which adapts them for either gate configuration. Most HO rule sets require tracks to provide voltage between 18.5 and 19.0 volts, and at least 5 amperes per lane; 1:24 racing is usually at 14 volts for qualifying and 12 under racing conditions. Lead-acid batteries or electronically-regulated power supplies are used to achieve this, though batteries are not used at national UFHORA events due to their inconsistent voltage.
HO Scale competition tracks are typically between 60 and 100 ft in length and 4 to 6 lanes wide. Many of the HO tracks used for competition are built from the plastic sections that are sold in race sets. These are often called "clickety-clack tracks" from the noise cars make crossing the joints. Some sectional tracks are made smoother by gluing the segments together, filling the gaps, and installing continuous power rails. Both types are referred to as "plastic tracks." For smoothness and consistency, they are generally considered inferior to "routed tracks," in which all the slots are cut into one or more large panels of wood or other material.
1:24 Scale tracks used for competition are generally 6-8 lane routed tracks with either wooden or flexible plastic retaining walls (so called "soft walls"). The tracks are usually located in commercial or purpose-built racing centres. Most of the tracks used in the USRA regional and national events are either original American Raceways (AMF) commercial tracks or copies of these designs made from original blueprints. Generally tracks used for regional or national competition have an epoxy or polymer painted surface with braided electrical contacts. In USRA division 1, the use of traction enhancing compounds on the racing surface ("glue") is allowed.
The most popular type of 1:24 track is the "Blue King" (155 feet) which is the track that is recognized for world records in 1:24 racing. The current (2006) world record qualifying lap is held by Benny Justice at 1.4632 seconds, which computes to an amazing 105.93 feet per second! The "King" track is unusual in that the segments are "named" starting from the main straight in an anti-clock wise direction: bank, chute, deadman (corner), finger, back straight, 90 (corner), donut (corner), lead-on, and top-turn.
[edit] Competition classes
HO Racing Classes
HOPRA and UFHORA run similar classes and similar rules for those classes. The following are brief explanations of some of those classes.
General rules specify the size of the car and anything else that pertains to all classes.
Superstock (HOPRA and UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). All magnets must be ceramic. Motors must be stock, and may be balanced and/or trued (referred to as "hot-stock").
Modified (HOPRA): Also known as "ceramic modified" is the same as superstock above, but the motor is unrestricted and the chassis may be sanded.
Modified (UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). Motor magnets must be ceramic, traction magnets may be polymer. Motor must have a resistance of no less than 3.0 Ω on each pole.
Polymer Modified (HOPRA)/Restricted Open (UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). All magents may be polymer. Motor is unrestricted. Chassis may be sanded. Shunt wires may be used.
Unlimited (UFHORA and HOPRA): No restrictions. Custom chassis permitted. Six neodymium magnets are usually employed.
1:24 Racing classes
Most 1:24 racing series use some variation of the USRA rules. The USRA rules have their roots in the NCC rules of 1971 which were written with the goal of making a number of under-classes in slot racing to allow more diversity in competition.
USRA Division 1:
a) Spec-15: Amateur only
b) GP-12: Amateur and Expert
c) International 15 (15A): Amateur and Expert
d) Cobalt 12/15: Amateur and Expert
e) Group 27: Amateur and Expert
f) Group 7 (open): Semi-Pro and Pro
There is also a class in its genesis called "One Motor Only" that is similar to Group 7 with the difference being that motor changes after tech are not allowed.
USRA Division 2:
a) Group 10 Stock Car
b) Production 4 1/2" Stock Car
c) GTP
d) GT-1
e) GT-12
f) C-12e
g) Eurosport
USRA Division 3: (Proposed)
a) Nostalgia Can-Am
b) Vintage NASCAR
c) Nostalgia F1
d) TSR
e) Vintage "Thingie"
F-2000
F-2000 is raced primarily in the midwest; it is a variation of the USRA rules with the prime exception being traction/braking "glue" is not allowed to be applied to the racing surface by participants.
See the current edition of the USRA rules for technical specifications and approved parts for USRA "group" racing classes.
Other international organisations such as the IMCA have their own classifications and technical regulations. Contact the organisation directly for their latest rules and series schedule.
[edit] Competition formats
Several race formats are employed in competition as time allows. The quickest to run is called round robin, which can be run in either of two ways. The first (and least common) way is begin with one driver on one lane of the track, a segment usually consisting of 2 minutes is run in which the driver attempts to complete as many laps as he can.
The second (and most common) way to run a round robin is to have four drivers (or as many as there are lanes) start at a time, and rotate through all the lanes, before being replaced by the next set of drivers. This is known as a "heat" or "consi". Often a small amount of practice time (usually 30 seconds) will be given to the drivers prior to the start of each heat. If there are an odd number of drivers such that they are not wholly divisible into the number of lanes, one of two measures is taken: either a heat is run with one or more positions unfilled, or a heat is run with extra drivers, with a "sit-out" position. After all drivers have run their heat, placement is determined by total laps completed.
Often round robins are modified to include a "main" and sometimes also a "last-chance" heat. When run with a main, the round robin is run as normal, but at the end the top competitors (as many as there are lanes) run an extra heat. This heat is usually longer (3 to 5 minutes per segment, 1.5 "pit" time, and 1 minute practice before the heat). At the end the drivers are re-placed based on the new lap totals.
Last-chance heats are similar to mains. The top competitors (number of lanes minus one) from the round robin move into the main, and the runners-up (as many as there are lanes) are moved into the last chance heat. The last chance heat is run before the main, and is usually run with the same time parameters as the other heats. At the end, the top competitors from the last-chance are re-placed based on their new lap totals (though never lower than a comptetitor that didn't make the last-chance), and the winner of the heat moves into the final position in the main.
Bracketed formats are usually reserved for national events, and include qualifying, elimination consis, semifinals, and a main.
"Marshals" (or "corner marshals"), usually consisting of drivers waiting for their turn on the track, stand around the edge of the track and replace any car that falls off. The lanes are generally colour coded or numbered and each race car has a sticker indicating the lane colour or number that that car is racing in. This is to help the marshall properly replace the car in the correct lane if and when it should happen to come "out".
When the segment time has elapsed, a small amount of time, usually one minute, is given for the driver to switch lanes, perform any necessary maintenance to his car, and return his car to its resting position (albeit in a different lane). At the same time, the next driver in the succession moves into the first lane, placing his car at the starting position. When a driver completes all the lanes, his total laps and final position are recorded. This continues until all drivers have completed all lanes. Lap totals are compared to determine placement.
Most racing organisations allow a "track call" (where the power is turned off) for a situation where a race car is in the wrong lane. This is also referred to as a "rider" and is considered to be a dangerous and unfair situation. Track calls are also sometimes used in the event that a car flies off the table and cannot be located by a marshal.
[edit] See also
- Goop tire adhesive
- Scalextric Longest established commercial manufacture of model slot cars
- Matchbox (toy company) briefly produced a commercial slot car brand called Powertrack in the 1970s
[edit] References
- ^ Smeed, V. "Simple-Electric Car Racing", 1st Ed. 1965.
- ^ Hertz, L.H. "The Complete Book of Model Raceways and Roadways", 1st Ed. 1965.
- ^ Hertz, L.H. "The Complete Book of Model Raceways and Roadways", 1st Ed. 1965.
- ^ "Model Car Science" magazine, October 1965.
- ^ Greenslade, R.W. "A History of Electric Model Roads and Racetracks", 1st Ed. 1985 ISBN 0-94-8793-007.
- ^ Greenslade, R.W. "A History of Electric Model Roads and Racetracks", 1st Ed. 1985 ISBN 0-94-8793-007.
- ^ Hertz, L.H. "The Complete Book of Model Raceways and Roadways", 1st Ed. 1965.
- ^ Hertz, L.H. "The Complete Book of Model Raceways and Roadways", 1st Ed. 1965.
[edit] External links
- [1] The origins of slot car racing
- A history of commercial slot racing
- E-Ticket Racing Slotcar Drag Racing Site
- HO Slot Car Racing
- SlotSide
- BW-Slot - German 1/43 site (also in English)
- OWH Slot Car Talk and Online News
- information on digital slot racing
- H.O. Slot Car Racing Portal
- British Slot Car Racing Association
- XSRDragRacing.com - Western Australian 1/24 drag racing
- WSMCR.com - Sydney 1/24 drag racing
- United Slot Racer's Association - USRA Home Page
- Scale Auto Racing News - reporting since 1979
- Auslot Forums- Australian Slot Car Discussion Forum
