What we need to end up with is the positive pick up on the right (when facing the "obvious" way - looking down on the track in the direction of travel). There’s two ways of doing that –

1 – The silly way – swap over the battery terminals and blow up every electronic controller. (The bottom row of Diagram T shows how to wire up a big bang for controllers!)

2 – The right way – swap over the input wires where they join the track (Diagram T top right).

We then all swap over the lead wires on our cars – a job everybody who competed at the Doowenip 1/24 BOC last year managed with little difficulty – and we are all up and running again with a package that’s more attractive to newcomers.

How do you get an extra circuit in your club room with an evenings work? Simple run round the existing one in the opposite direction. This works well on a number of circuits – Pinewood, Riverside and Oaklands have run successful BOC meetings in both directions. As anybody who has tried it will know, a track in the reverse direction drives like a different track – you’ve got to learn it all over again! There are other differences– marshalling positions are a little different because cars fall off after the exit to corners rather than before the entry. Some tracks designs that work better in one direction than the other because of the following

Marshals in different positions may block the drivers view.

Marshals may have better access to the entry to a corner than the access

There may be more accidents under the bridge

There may be bumps / track joints that upset cars a lot more in one direction than the other.

If you go for a track that can be run in both directions, the change in polarity becomes a trivial issue. Some clubs may take the opportunity to wire their track to be used either way – its not much more work if you are reversing the polarity anyway. There are various ways of doing it.

1 Use a two pin connector on the feed to each lane, and put the plug in the other way up to reverse the polarity. This is how Oaklands and Ecurie Barnton do it.

2 Use a relay in the feed to each lane to swap the polarity. The switches for the relay can either be on race control (as at Bournemouth) or on the driver’s rostrum (as at Vauxhall).

(Cars wired to the 2003 standard will go in the reverse direction with the switch in the 2002 position. Cars wired to the 2002 standard will go in the reverse direction with the switch in the 2003 position.)

The other thing that needs checking before reversing polarity is will the counters work? The optical detectors used on some tracks will be unaffected, but where the counters use a dead strip or split tape where the counters are connected to the track wiring there is a possibility that they will not work. In fact most counters do work either way round, but there are so many different types in use its difficult to say how many will be affected. The only sound advice I can give is get somebody who understands how your counters work to check it over first…… and make any necessary changes so they work correctly.

How long it takes to modify a particular track will depend on how it’s wired in the first place. At the simplest, where there are a single pair of feeds to each lane, its just a question of swapping the wires over so it should only be a half hour job. Bournemouth was rewired for reversible polarity by one person in one evening. 

Some tracks are wired with the negative going to the track directly (for example the Wildfields AKA "UK Black" Nationals track is wired like this), and the E pins of the controller socket connected to the track.  If it is done this way, there is a need to swap over the feed from the battery to the other tape on each lane as well as swapping over the wires to each socket.

The formal change over date will be 1st January 2003, this has been arrived at after considerable consultation with clubs. We can do without a practical slot racing version of the old joke about changing over from driving on the right to the left over a period of months!

 If you fancy being able to run your track in both directions, obviously you can modify the track as soon as you like, and you’ll be ready for the change over at the flick of the switch.  

What does our club need to do?

Take a look at your track wiring and work out how to change the polarity. Clubs with tracks which are usable in either direction should be strongly encouraged to make changes so that the polarity can be easily reversed. This can be done as soon as convenient.

If you are going to simply change polarity, rather than go for the reversible option, you should aim to change over at the end of this year,  the formal change over day will be 1st January 2003.

If your club is running to the old polarity after 1 Jan, (or the new polarity before 1 Jan) please tell competitors in advance of the meeting. This will save any embarrassment with people turning up with their car wired to go backwards on your track.

Need Further Advice

I've tried to make this article as helpful as possible, but no doubt there's something that could be better explained. If you have any further questions on  how to change polarity, (or any other aspect of track building) e mail me at slot_racing@yahoo.co.uk and I'll try and help. If it looks like a question that would be helpful to a wider audience, I'll update these web pages as well.

Chris Frost