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Introduction

North London SME invite you to join in an informal series of races re-creating some of the spirit of 1/24 scale racing in the UK in the 1967-72 period. We’d like you to build or revive real period style cars. If you’d like to see some chassis styles look at magazine reports from the period or ask John Secchi, Ian Fisher etc. for more information. If you’d rather not use or build a true period car, you can also take part using a modern Production chassis with minor changes and a period bodyshell.
Racing classes will depend on interest shown. Initially just Sports/GT. If there are lots of cars we could sub-divide into say, inline chassis, pre and post 1970 anglewinders, production chassis. Anyone for single seaters?
For suitable body shells see the Betta range. Also several US and other foreign suppliers have some older, scale appearance shells available. Some are made on the old moulds. Or dig out true period equipment.
For front wheels, Parma make an attractive scale front wheel, or there are many old ones still about.
For motor parts, see older racers’ bits boxes, or try suppliers for stuff they couldn’t sell!
In chassis, at the start of the period, chassis were simple with a few rails front to rear of an inline motor with body outriggers. These soon started to be hinged allowing the body to tilt on corners. Side pans developed either from multiple brass rod (a ‘raft’ chassis) or brass plate.
The ‘anglewinder’ was the sensational development with a truly amazing variety of styles through 1968/9. Later the cars at Tottenham Model Raceways copied US raceway practice and typically had a ‘2 ½ rail’ frame with reverse-iso on the drop arm. Car weights were substantial by modern standards, rarely below 120g and often 150g.
Motors started as modified Mabuchi 16D and 26D types. Better magnets became available allowing hotter armatures to be used and 25g and 24g US winds were common on the raceways. Mura and Champion then started to make whole motors developing quickly through to ‘B’ and just into early ‘C’ cans in our period. On modern club tracks you may find the really hot older motors rather brakeless!
Anyway, to get you started on building or modifying, here are the regulations we have drafted. They are based loosely on the Association of Raceway Centres (ARC) rules published in April 1970 Model Cars magazine. ARC was a loose association of London and a few other commercial raceways.
We have only prepared car regulations. All other race regulations will be to current BSCRA practice.

Car Regulations
Cars will be 1/24 scale, classed by body type in the following classes.
Sports/GT Class
Models of real cars built prior to the end of the year 1972, open or closed and having no more than two seats.
Saloon Class
Models of real cars built prior to the end of the year 1972, closed cars only, having at least four seats.
Single Seater Class
FI / Indy Class for pre 1972 cars

Specific Requirements for the Closed wheel classes
Bodies
1. Bodies must be near exact replicas of actual cars.
2. Transparent windows and windscreens must be fitted in the all locations as on the real car.
3. Bodies must display at least two sets of racing numbers.
4. Bodies must be securely mounted to the chassis.
5. Closed wheel bodies must cover the tread of all tyres
6. Bodies must have a realistically positioned and painted driver figure with three dimensional helmet, shoulders, arms and steering wheel.
7. The chassis and motor must not be visible through the cockpit or cabin area.
8. Bodies must be fully painted and detailed, including all air vents, engine and mechanical detail where shown on the body shell.
9. The front wheel arches need not be cut out, but must then be left transparent so that the full front wheel is visible.
10. Air Control Devices
On Sports/GT cars only, the following are permitted. All must be firmly secured to the body or chassis.
Spoilers (Rear of Car)
1. One spoiler maximum.
2. Spoiler must not lengthen the car by more than 1/8 in. (3mm).
3. Spoiler must not be taller than ½ in (13mm) above the local height of the body shell.
4. Overall height of the car must not exceed 1½ in. (38mm) from the track surface.
5. Spoiler must not extend beyond the widest part of the moulded body shell.
Side Dam Spoilers
1. Dams on the end of the spoiler may not extend further forward than a point 1 in. (25mm) from the centre line of the back axle. Dams shall not exceed the height of the spoiler and shall taper uniformly so that they are level with the body shell at their forward edge.
Diaplanes (Front of Car)
1. One diaplane maximum.
2. Diaplane must not lengthen the car by more than ½ in. (13mm).
3. Diaplane must not extend beyond the widest part of the moulded body shell.
Trim Tabs
1. One trim tab is permitted in the centre of the body (in front of the windscreen), or alternatively one trim tab is permitted on each of the two front wheel arches, maximum size for 2 tabs is 13 m/m [ ½ “] square each or 26m/m [ 1”] long and 13m/m[1/2”] high for single tab
11. To remain within the spirit of this class of racing, the body should be cut out close to the marked cut line on commercially available body shells. On all closed wheel cars, the minimum height of the tallest part of the shell directly above each front wheel shall be 25/32 in. (20mm) from the track surface. All add on air devices are to be in clear materials.
Chassis
12. Any chassis actually built in 1972 or earlier will be accepted provided there is reasonable evidence to support date claims. This will normally by comparison with known chassis styles from a range of period documentation.
13. Any more recent hand built or partly hand built chassis shall be in the style of 1972 or earlier slot car chassis designs. Again this will normally by comparison with known chassis styles from a range of period documentation.
1. Spring steel sheet shall not be used unless it can be shown that the chassis actually dates from 1972 or earlier. ‘Flexi-boards’ and other later type design features shall not be used.
2. On anglewinder and sidewinder chassis, full front and rear axles shall be fitted between the wheels, straight and able to rotate fully.
3. No track skids shall be fitted.
14. As an alternative, a chassis complying with the current BSCRA 1/24 Production class may be used, with wheel dimensions and ground clearance as per rules.

Motors
15. The following motors and parts only are permitted.
1. Any motor intended for slot racing and sold in 1972 or earlier.
2. Any ‘C’ can motor with a Mura or Champion can of .030 in. material and of a type without lightening around the endbell mountings. The can must be standard length and magnets must be one piece type.
3. Any 16D type motor. The can must be standard length and magnets must be one piece type.
4. Any type of bearings, brushes and brush springs may be used.
5. The minimum armature diameter is .500 in. (12.7mm). The minimum armature stack length is .425 in. (10.8mm) for armatures up to .530 in (13.5mm) diameter. The only exception to this is that standard Mura G12 armatures may be used.
Guide and Pickups
16. Only one slot guide is permitted per car.
17. The guide must be a commercially available type from any period.
18. The guide must not be visible from above the car unless the body extends less than 1 1/4 in. (32mm) forward from the centre of the front axle. In that case no part of the guide or pickups shall be more than 1 1/4 in. (32mm) in front of the centre of the front axle.
Axles
19. Axles may not extend beyond the outside rim of any wheel. They shall be made of steel. Hollow axles are not permitted.
Wheels and Tyres
20. All four wheels shall touch and roll on level track surface at all times.
21. The dimension limits are
Front - Minimum 5/8 in (15.9mm) diameter. Note: ¾ in is preferred.
Minimum 3/16 in. (4.8mm) width.
Rear - Minimum ¾ in. (19mm) diameter.
Maximum ¾ in. (19mm) width.
Any tyre material is permitted for the driven wheels. Non-driven tyres must be plastic or rubber and coloured black.
22. All wheels must be fully visible in the wheel arches.

Other Car Dimensions
23. Maximum overall width of any part of the car is 3-¼ in. (83mm).
24. The minimum track clearance is .047 in. (1.2mm) at the front of the car, .062 in. (1.6mm) at the rear axle. No intermediate part shall be lower than the front limit. The only projections below these limits shall be the wheels, tyres and slot guide.
Weight update advised 26.01.03
Inline sports chassis [copy]Min Weight 100 Gram
Aglewinder Sports chassis [copy] Min Weight 120 Grams
Inline F1 and Saloon [copy] , these classes had not been considered when we adapted these rules so we will accept Min 100Grams for these as well.
For all pre 72 [will need reasonable proof] chassis of all configuration there will be no Min weight limit or configuration limit [ angle winder F1
Etc, Etc].
For all modern Production anglwinder chassis Min 140 Grams at first meeting used, added weight penalty at race directors discretion at any subsequent meetings [this is to get people to make some effort to obtain or build a retro type chassis].
Modern inline production chassis [if/when available] will have a Min weight limit decided upon at the time of the first meeting they appear at by the race director/series organiser.

The 1/24 F1/Indy :
BODIES: Any non side tanked pre 1972 F1 or Indy cars can be used [ cigar shape], they must be painted in the original colours as per the prototype and carry race numbers in the correct position as the original, a well detailed 3 dimensional painted interior [as period as possible] to be fitted. Any weird and wonderful odd-ball original cars that would have raced up to that date regardless of what chassis configuration will be eligible, but must proven to be original.
CHASSIS:
[A] Any commercially available 1/24 pre 1972 inline chassis
[B] Any original scratch built 1/24 pre 1972 inline chassis
[C] Any scratch built copy of a 1/24 inline chassis of a type and design that might have run pre 1972 of brass or stainless steel and wire [ no spring steel except for guide tabs] in its construction and must use a "U" bracket on the drive end [ twin motors are OK as are 4WD ]. The chassis will have a Max width of 40 mm along its full length, bearings free choice.
MOTOR: Any original pre 1972 [ or made up of original parts ] motor or up to a modern S16D, bearing free choice
WHEELS: FRONTS Min diameter is 3/4" Min width is 1/4" --- REARS Min diameter 3/4 Max width is 3/4"
CLEARANCES: Max overall with is 83 mm , max chassis width is 40mm [ excluding body fixings] and ground clearance is .062" [ 1.2mm] under the complete chassis except for guide shoe.
OTHER:
[A] No part of the chassis or guide must be visible when viewed from above
[B] Any wings that are fitted to the model must be in proportion and in the correct position as per the original prototype.
[ C] Any axle type or size can be used, free choice.

Copyright J Secchi