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Fried chips and smokin’ motors – Keeping the vital parts of a Scalextric car cool by understanding “duty cycle”

In order for your Scalextric car to give the best and ongoing performance it is necessary for the key components not to get too hot. The key components discussed in this article is the motor and the digital chip (if fitted). This article uses the notion of “duty cycle” to keep your Scalextric cars cool and running well.

Duty cycle
In this World not all machinery or equipment is capable of running or operating continuously. Some equipment needs to be serviced, some may wear out and some may get hotter and hotter in use. This would indicate that the equipment needs a period of rest between usage periods. This “on” verses “off” time is known as the duty cycle.

Scalextric duty cycle

For example one of our instant soldering guns can be used for 12 seconds but must then rest for 40 seconds to allow the transformer to cool down. After the 40 seconds cool down period it can be used again for 12 seconds, etc. This on / off period is known as the duty cycle for this soldering gun.
Duty cycle may be expressed in time as in the soldering gun example or as a percentage. For example a 75% duty cycle could mean the equipment can be operated for 3 minutes and then rested for 1 minute.

Smokin’ Scalextric motors
None of the motors used in any of the Scalextric cars is capable of continuous racing conditions. They are capable of long term use at slow speeds. As the race continues the motor is unable to dissipate the heat it generates and the motor just gets hotter and hotter. That is until the internal solder joints melt and the motor stops working with permanent damage.
Sometimes a tiny amount of oil contamination on the commutator will start to burn and the motor will emit smoke and smell of burning.
It therefore follows that a Scalextric motor has a duty cycle to let the motor cool down between races. All motors, cars and track layouts will be different but to be safe it is best to assume a duty cycle of 50%. That is race for 5 minutes and let the motor cool for 5 minutes, or race for 10 minutes and let the motor cool for 10 minutes. I’m sure you’ve got the idea by now.

Fried Scalextric digital chips
The Scalextric digital chip is nothing more than some basic electronics and a single micro chip computer to manage the communication side of things. The chip has 3 main sections; the power supply, the micro processor and the motor power drive. Even when operating in analogue the chip is still regulating the power to the motor. Note, there is no overcurrent protection on the Scalextric digital chips.
The power supply and micro processor are well enough designed to not usually cause a problem. The cause of failed digital chips is the motor power drive transistors. These drive transistor turn on and off many times a second to control the power to the motor. The transistor on time and off time is controlled by the micro processor based on the hand throttle position.
When the motor power transistors are switched on they effectively become low value resistors allowing the electrical current to flow through the motor. When the transistors are switched off they effectively become high value resistors stopping the electrical current from flowing through the motor.
When the motor power transistors are switched off there’s no current flow and therefore no heat generated within the transistors. Therefore off is no problem for heat generation.
When the transistors are switched on, the full motor current passes through the transistors and heat is generated within the transistors. So, the more on time the more heat generated per unit time. The more on time, the more power to the motor, the harder the motor is working, In this case full speed racing will generate more heat in the motor power transistors and as this heat builds up there comes a point where the internal silicon of the transistor effectively melts. This will destroy the transistor function – fried chip.
Again the Scalextric digital chip has a duty cycle depending on the chip installation, motor, car and track layout. In this case Silicon cools very quickly so a duty cycle of 75% would be OK. However, we should limit the race time to prevent the heat building in the first place. We recommend not racing for more than 5 minutes to prevent permanent damage to the Scalextric digital chips.

Article from Scalextric Car Restorations

New tyres for the Tri-ang Jump Jockey set

These new tyres are direct replacements for the original tyres fitted to the Tri-ang Jump Jockey sets, see above image. They are available in MAX Grip versions.
The new hand made MAX Grip tyres are unique to Scalextric Car Restorations and give the absolute maximum in performance at all times. Cornering and acceleration will all be at their maximum with these tyres. They give the very best performance possible on all track surfaces at all times. Simply put we have not yet discovered a better tyre for grip and race performance.
The MAX Grip tyres are hand moulded from 29 Shore A hardness rubber which is a very high grip material.

The tyres are smooth treaded and have a smooth tyre sidewall.

http://www.scalextric-car.co.uk/Parts/Tyres_Triang/Triang_Tyres_Jump_Jockey/Triang_Tyres_Jump_Jockey.htm
http://www.scalextric-car.co.uk/Parts/Tyres_Triang/Triang_Tyres_Jump_Jockey/Triang_Tyres_Jump_Jockey.htm
Dimension
Size (mm)
Outside Diameter
11.0
Inside Diameter
4.5
Overall Width
3.0

MAX Grip tyres from Scalextric Car Restorations

Fitting instructions for a Scalextric motor pinion gear – 9z

This process does not require specialist gear pullers or other tools

 

1. Place the gear on a hard surface
Warm the gear to at least 30 degrees centigrade which will allow the plastic to stretch over the motor shaft without splitting. Simply holding the gear in a warm, closed hand for a few minutes will be sufficient or soak the gear in a container of warm water for a few minutes.
Place the gear on a hard surface with the circular flange facing upwards.
2. Gently push the motor shaft into the gear
Gently push the motor shaft into the hole in the centre of the motor pinion gear. Use a constant gentle downward pressure.
Continue until the motor shaft is right through the gear and touching the hard surface.
3. Pinion gear partly fitted
Here the motor pinion gear is partly fitted. The shaft is flush with the face of the gear.
4. Pressing the gear into the final location
Position the motor shaft over a void or hole in the hard surface. In this picture a gap in the jaws of the pliers is used.
Again apply constant and gentle downward pressure to push the gear along the motor shaft and into the correct final position.
5. Motor pinion gear fitted
Here the motor pinion gear can be seen in the correct final location along the motor shaft.
The exact location may depend on your specific application.

Note:
This pinion gear is used to service several different types of motor pinion gears fitted to several different Scalextric motors used over the years (decades). With some motors, especially those with poor or missing spines it may be necessary to reduce the diameter of the internal hole of the pinion gear. This will ensure the pinion gear is a good tight fit onto the motor shaft.
To do this, use an opened up paper clip to smear a little superglue on the inside of the pinion gear. Allow the superglue 1 hour to set fully before a trail fitting the pinion gear to the the motor shaft. What you want is a good tight fit where the pinion gear will slide onto the motor shaft with a some effort. Add another smear of superglue onto the inside of the pinion gear if necessary. Allow this to dry fully for 1 hour before trail fitting again. Repeat as required.

Great ideas from Scalextric Car Restorations

Scalextric slot car Neodymium magnatraction magnet kit

Improved track performance with minimal effort.

These Scalextric spares Neodymium Iron Boron magnets have a gauss level which is typically 2 – 4 times higher than standard Alnico magnets. They are nickel-plated for improved corrosion resistance and appearance.

They are suitable for all slot cars; Artin, Ninco, SCX, Scalextric, SCX Scalextric, Tri-ang and many more.

This kit is great if you are not sure which Scalextric spares magnets would be best suited for your car.

http://www.scalextric-car.co.uk/Parts/Magnetraction/Magnet_Neodymium_Selection/Magnet_Neodymium_Selection.htm

This kit contains:

Quantity
Description
2
Bar magnet 12mm x 6mm x 1.5mm (1/2″ x 1/4″ x 1/16″ approx.)
2
Bar magnet 25mm x 6mm x 1.5mm (1″ x 1/4″ x 1/16″ approx.)
1
Bar magnet 25mm x 6mm x 3mm (1/2″ x 1/4″ x 1/8″ approx.)
2
Button magnet 8mm x 3mm (1/4″ x 1/8″ approx.)
2
Button magnet 8mm x 5mm (1/4″ x 3/16″ approx.)
1
Button magnet 10mm x 5mm (3/8″ x 3/16″ approx.)
Please see our Neodymium Magnet Safety Page for further information.
Our unique Magnet Downforce Calculator gives the magnetic attraction force for this magnet at given distances from the track. Ideal for locating the magnet.

Scalextroc spare parts from Scalextric Car Restorations.

Windscreen for the vintage Scalextric C69 Ferrari 250 GT

This windscreen is new and a direct replacement for the vintage Scalextric Ferrari 250 GT Berlinetta windscreen. This window moulding comprises all the windows, front, back and sides, for this Scalextric Ferrari Berlinetta model.
It is moulded in a fully clear material.

http://www.scalextric-car.co.uk/Parts/Windscreens/Windscreen_C69_Ferrari_250_GT/Windscreen_C69_Ferrari_250_GT.htm
http://www.scalextric-car.co.uk/Parts/Windscreens/Windscreen_C69_Ferrari_250_GT/Windscreen_C69_Ferrari_250_GT.htm
Ref.
Description
C69 Ferrari 250 GT Berlinetta
E4 Ferrari 250 GT Berlinetta

Scalextric spare parts from Scalextric Car Restorations.

Windscreen for the vintage Scalextric C68 Aston Martin DB5

This windscreen is new and a direct replacement for the vintage Scalextric Aston Martin DB5 windscreen. This window moulding comprises all the windows, front, back and sides, for this Scalextric Aston Martin model.
It is moulded in a fully clear material.

http://www.scalextric-car.co.uk/Parts/Windscreens/Windscreen_C68_Aston_Martin_DB5/Windscreen_C68_Aston_Martin_DB5.htm
http://www.scalextric-car.co.uk/Parts/Windscreens/Windscreen_C68_Aston_Martin_DB5/Windscreen_C68_Aston_Martin_DB5.htm
Ref.
Description
C68 Aston Martin DB4
C97 Aston Martin DB4 007 **
E3 Aston Martin DB5 with lights
E5 Aston Martin DB5 Marshal’s Car

** Some modeling skills are required to cut the sunroof aperture.

Scalextric spare parts from Scalextric Car Restorations

Scalextric Aston Martin DB10 – C1336 Spectre set

This Scalextric C1336 Aston Martin DB10 – is new and unused, it is complete with all parts present and correct and has been removed from the Scalextric C1336 Spectre set.

http://www.scalextric-car.co.uk/Cars/C1336A_Aston_Martin_DB10/C1336A_Aston_Martin_DB10.htm

The Aston Martin DB10 is fitted with its new and unused pick up braids. The body has no scratches or other marks and the factory applied decals are in perfect condition. The neodymium magnatraction magnet is fitted. The new tyres are in good, grippy condition. The white LED headlights illuminate well as do the red LED tail lights.
This unused Scalextric Aston Martin DB10 model is in wonderful condition and would add significant value to any collection. Simply put this car is just as it was when it left the factory.

Scalextric cars from Scalextric Car Restorations