Magnets in Scalextric motors

Keeping the Scalextric motors at their best by keeping the magnet strong

Introduction

The electric motor in all Scalextric cars produced to date uses a 3 pole wire wound armature and a permanent magnetic field. Over the years 3 general types of magnet has been used, in the 1960 a ferrous (Iron based) block magnet was used then from the 1970s two shaped magnets have been used. More recently some high performance motors have been produced using the stronger shaped neodymium magnet.

This article relates to the earlier ferrous block magnet as fitted to the RX motor, Powersledge motor and the Formula Junior motor.

How a motor works

A motor works by having two magnetic fields attract / repel one another, just like two block magnets do. In a motor one magnetic field comes from the ferrous block magnet and one from the electrical current flowing in the wire windings. Therefore the stronger the magnetic field from the ferrous block magnet the more torque the motor will produce. The electric current is switched from winding to winding by the commutator as the armature rotates.

Magnetism

In any non magnetic ferrous material the spins of the electrons in the atoms of the material are randomised giving equal numbers of "up spin" and "down spin". It's the spin of the electrons that create the magnetic field. When the ferrous material is placed in a strong magnetic field the electrons all align so they spin in the same direction producing an overall magnetic field. The material has become magnetised.

However, the magnetised material is in a higher state of energy compared to non magnetic material. This means a ferrous block magnet will lose its magnetic effect when it can. To maintain the magnetic effect of a ferrous block magnet the magnet must be kept in a tight magnetic loop. This is why magnets when not being used use a "keeper". A "keeper" is a piece of magnetically conductive material that keeps the magnetic field in a fixed ferrous loop.

Magnets in motors

In a Scalextric motor the ferrous block magnet is kept in a tight magnetic loop using the steel motor frames and the ferrous core of the armature. In this way an assembled motor will retain its magnetism for many, many years. Each of the Scalextric motors that use the ferrous block magnet are magnetised as an assembled motor.

The problem with the Scalextric motors that use a ferrous block magnet is that if the magnet is removed from the motor, for any reason, it will immediately lose some of its magnetic field strength. Basic tests show that the magnet will be 20 to 30 percent weaker. There is no gain in magnetic field strength when the magnet is refitted to the motor. Do this enough times and the magnetic field will diminish to the point where the motor will not operate.

Conclusion

To maintain a healthy magnetic field strength the ferrous block magnet must be magnetised with the motor assembled. Specialists, like Scalextric Car Restorations, have the equipment to do this. Completely "dead" magnets can be brought back to life and the magnetic field can even be reversed in just a second. Reversing the magnetic field will change the direction of rotation of the motor.

Neodymium magnet for the vintage Scalextric RX motor

This new Neodymium magnet can be used on all the vintage Scalextric RX motors including the 'Race Tuned' versions. The picture above shows the Neodymium magnet fitted to the RX motor.
Improved track performance with minimal effort. This magnet will give your RX motor more torque and more speed.
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.
Fitting instructions.

• Remove RX motor from the Scalextric car
• Undo and remove the nut and bolt securing the original steel magnet
• Remove the original steel magnet from the RX motor
• Carefully position the new Neodymium without trapping fingers. Note the red mark should face towards the underside of the motor, i.e. away from the brush spring and towards the securing nut.
• Refit the nut and bolt
• Refit the RX motor to the Scalextric car

Please see our Neodymium Magnet Safety Page for further information.

Ref.	Description	Type
C1	Alpine Renault Race Tuned	RACE TUNED
C2	Matra Jet Race Tuned	RACE TUNED
C7	Rally Mini Cooper - Type 1 to 6
C12	Matra Jet Race Tuned	RACE TUNED
C25	Ferrari 312B2 - Type 1
C26	March Ford 721 - Type 1
C32	Mercedes 250SL
C34	E Type Jaguar
C36	Honda GP
C37	BRM
C41	Ferrari GT 330
C43	McLaren M9A
C44	Mercedes Wankel C111
C46	Porsche 917K
C48	Tyrrell Ford 002
C50	JPS Lotus 72 - Type 1
C54	Lotus 16
C55	Vanwall
C56	Lister Jaguar
C57	Aston Martin DBR
C58	Cooper
C59	BRM P25
C60	D-Type Jaguar
C61	Porsche Spyder
C62	Ferrari 156
C63	Lotus 21
C64	Bentley 4.5l (1929)
C68	Aston Martin DB5
C69	Ferrari GT Berlinetta
C70	Bugatti type 59
C71	Auto Union C type
C74	Austin Healey 3000
C75	Mercedes 190SL
C88	Cooper Race Tuned	RACE TUNED
C89	BRM P25 Race Tuned	RACE TUNED
C90	Ferrari 156 Race Tuned	RACE TUNED
C91	D type Jaguar Race Tuned	RACE TUNED
C92	Porsche Spyder Race Tuned	RACE TUNED
C93	Austin Healey 3000 Race Tuned	RACE TUNED
C94	Mercedes 190SL Race Tuned	RACE TUNED
C95	Bugatti type 59 Race Tuned	RACE TUNED
C96	Auto Union C type Race Tuned	RACE TUNED
C97	Aston Martin DB5 007 set
C99	Fiat 600 Race Tuned	RACE TUNED
E1	Lister Jaguar with lights
E2	Aston Martin DBR with lights
E3	Aston Martin DB5 with lights
E4	Ferrari GT Berlinetta with lights
E5	Aston Martin DB5 Marshal's Car

 Great Scalextric spares from Scalextric Car Restorations

How to service the RX motor in your Scalextric car – updated

Maintain your Scalextric car’s RX motor with these simple hints and tips

Abstract

The earlier Scalextric cars produced in the 1960s were fitted with open frame motors the most common of which is known as the RX motor. This motor was also fitted to many of the Hornby locomotives of the period. This article shows how an RX motor can be serviced in a methodical way by considering the mechanical, electrical and magnetic aspects of the motor.

Introduction

The RX motor was fitted to most Scalextric cars from the 1960s. In order for your Scalextric car’s RX motor to give the best possible performance it has to be in the best possible health. Effectively giving the maximum torque for the electrical power available to it. For any electrical motor to give its best 3 key areas need to be considered; the mechanical condition of the motor, the electrical condition of the motor and the magnetic condition of the motor.

Mechanical

Mechanically the RX motor needs to be in the best condition possible to ensure that no energy is lost and the motor can transfer all of the generated torque to the rear axle. To do this several areas need to be reviewed:

• Firstly check and ensure that all the parts are present and undamaged. All missing or damaged parts must must be replaced.
• Check and ensure the motor armature spins freely with no rubbing or tight spots. This could be caused by missing or damaged bearings or a damaged motor housing.
• Review the motor pinion gear and ensure all the gear teeth are in good condition. Replace the pinion gear if gear teeth damage is found.
• Add a drop of oil to each of the bearing felt pads.
• Ensure the brush spring sleeve is present and in good condition. Replace if necessary.

Electrical

There are many electrical connections and contacts used on the RX motor. Each of these must be in good condition to ensure the best performance of the motor. To do this several areas need to be reviewed:

• Firstly check and ensure that the solder joint between the wire from the pick-up brush and the eyelet that fits over the brush spring sleeve is complete and sound. Replace or remake this joint if any of the wire strands are broken or not making contact.
• Inspect the eyelet for any dirt or metal oxides that may have formed over the years. Clean the brush spring back to clean shiny metal where it contacts the motor brush.
• Inspect the brush spring for any dirt or metal oxides that may have formed over the years. Clean the brush spring back to clean shiny metal where it contacts the motor brush and the screw that secures the magnet.
• Inspect and clean the motor brushes removing any dirt, oil and carbon deposits. Ensure the carbon block is present and securely attached to the brass strip. Clean the motor brushes back to clean shiny metal where they contact the brush spring and eyelet.
• Remove any dirt, oil and carbon deposits from between the commutator segments of the armature.
• Remove any dirt, oil and carbon deposits from the commutator.
• Check the three solder joints that secure the armature windings to the commutator, remake these joints if necessary.
• The electrical connections for a car with an RX motor are:
  • Contact: Track braid to track rail
  • Contact: Braid contact to track braid
  • Solder joint: Wire to braid contact
  • Solder joint: Motor brush sleeve to wire
  • Contact: Motor brush to motor brush sleeve
  • Solder joint: Motor brush carbon block to motor brush
  • Contact: Commutator to motor brush carbon block
  • Solder joint: Armature wire to commutator
  • Solder joint: Armature wire to commutator
  • Contact: Commutator to motor brush carbon block
  • Solder joint: Motor brush carbon block to motor brush
  • Contact: Motor brush to brush spring
  • Contact: Brush spring brass bolt
  • Contact: Brass bolt to eyelet
  • Solder joint: Eyelet to wire
  • Solder joint: Wire to braid contact
  • Contact: Braid contact to track braid
  • Contact: Track braid to track rail

Magnetic

The magnetic field used by the RX motor is provided by a permanent magnet at the rear of the motor. The magnetic field reaches the outside of the armature by the use of steel plates that are also used as the housing for the motor. To ensure the magnetic circuit is maintained the RX motor uses various materials to ensure the magnetic field is not reduced. Over time the magnet can lose some of its magnet field strength thereby reducing the motor’s torque and top speed. A replacement Neodymium magnet is available to restore and improve the RX motor’s performance.

• Ensure the magnet is secured by the correct brass screw.
• Ensure both the steel housing plates make good tight contact with the magnet.
• Ensure the aluminum plate adjacent to the magnet is fitted correctly.
• Ensure the brass plate at the commutator end of the motor is fitted correctly.

General

Through experience we have found that some RX motors still do not perform well even with all of these checks completed. This may be caused by a weak magnet or internally damaged armature windings. These faults are outside the scope of this article. There are many other possible faults with the earlier cars with the open frame motors. This is intended as a simple fault finding guide only. If the information above does not resolve the fault then contact us for further information.

About the author:

Gary Harding has been working with Scalextric cars for over 30 years and now operates Scalextric Car Restorations in the UK. Scalextric Car Restorations is a Worldwide internet based business that offers for sale high quality Scalextric cars and Scalextric parts from the 1960s to the present day. All the restoration work is carried out to the highest standards with the highest quality parts available. Only the best cars are selected and the final result is a car that is genuinely like new.
Further help and advice relating to this article or Scalextric cars in general can be found at:
http://www.scalextric-car.co.uk

Scalextric motor Brush holder kit for the vintage RX motor

New replacement motor brush holder kit suitable for the vintage Scalextric RX motors.  This new Scalextric motor brush holder kit can be used on all the Scalextric RX motors used in vintage Scalextric cars including the ‘Race Tuned’ versions. The brush holder comes complete with the fixing rivet.

The picture above shows the brush holder kit fitted to the Scalextric RX motor.
Fitting instruction:

• Remove the RX motor from the Scalextric car.
• Remove the brushes, brush spring and wiring from the Scalextric RX motor.
• Use a permanent marker to mark the magnet to ensure it is refitted in the correct orientation.
• Remove the magnet from the motor.
• Remove the motor top plate.
• Drill out the existing brass rivet holding the old brush holder in place.
• Clean and inspect the motor top plate for damage.
• Push the rivet through the brush holder and the motor top plate. Rivet head to be on the outside of the motor.
• Use a small hammer or press tool to compress and tighten the rivet.
• Refit the motor top plate.
• Refit the magnet noting the correct orientation.
• Refit the motor brushes and spring.
• Refit the motor to the Scalextric car.

Another great Scalextric spare part from Scalextric Car Rerstorations

More power from a Scalextric RX motor

Introduction:
The earlier Scalextric cars produced in the 1960s were fitted with open frame motors the most common of which is known as the RX motor. This motor was also fitted to many of the Hornby locomotives of the period. This article shows how to produce more torque and more RPM from an RX motor.

There are 3 main factors involved in improving the performance of a Scalextric RX motor.  These are:

• Electrical
• Magnetic
• Mechanical

Electrical:
For electrical the first place to start is to clean all the electrical connections from the track braids to the motor brushes.  An alternative is to use a flexible silicon wire and make a new connection from each track braid to the motor brushes directly.  This removes almost all of the electrical connections.  More radically the motor armature wire can be replaced to give a higher electrical current.
More current gives more torque.
Magnetic:
Magnetically there’s a couple of solutions available.  Re-magnetise the existing magnet to get it the best it can be or simply replace the magnet with a Neodymium magnet.  This will give 2-3 times the magnetic field strength of the original magnet.
More magnetic field strength gives more torque.
Mechanical:
Mechanically it’s all about reducing friction that opposes the rotation of the armature.  With the motor brushes removed the armature should spin very freely in its bearings.  The bearings should be in good alignment and offer very little resistance.  The tension on the motor brushes can have a big effect too.  Reduce the spring tension and the Scalextric RX motor produces more torque and more RPM.
Less friction gives more torque.
About the author:
Gary Harding has been working with Scalextric cars for over 35 years and now operates Scalextric Car Restorations in the UK. Scalextric Car Restorations is a Worldwide internet based business that offers for sale high quality Scalextric cars and Scalextric parts from the 1960s to the present day. All the restoration work is carried out to the highest standards with the highest quality parts available. Only the best cars are selected and the final result is a car that is genuinely like new.
Further help and advice relating to this article or Scalextric cars in general can be found at:
http://www.scalextric-car.co.uk

Re-manufactured: Neodymium magnet for the vintage Scalextric RX motor

New replacement Neodymium magnet suitable for the vintage Scalextric RX motor.
This new Neodymium magnet can be used on all the vintage Scalextric RX motors including the ‘Race Tuned’ versions. The picture above shows the Neodymium magnet fitted to the RX motor.


Improved track performance with minimal effort. This magnet will give your RX motor more torque and more speed.
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.
Another great product from Scalextric Car Restorations