'Taming the Tiger' in your slotcar

Squeezing out those last few tenths

'Taming the Tiger' in your slotcar

Postby wixwacing » Sat 19 Jul, 2008 12:00 am

It's becoming more and more apparent that Messers Hornby and Co are going to continue to produce a range of slot cars with massive fine detail just asking to be snapped off at the first spearing out of control of your much loved model!! This can cause some to purchase duplications of a model purely and simply to have at least one good one in reserve. VERY expensive!!

While some models are fully adapted to high speed driving, having long, wide, flat profiles to aid in general traction by having a super low centre of gravity, there is a new breed of modern slot car which, from forum posts, is obviously a source of consternation to their owners. These people desperately want to race these models but fear the (inevitable) worst when it comes to actually putting them on the track!!

Magnet or no magnet, there are a range of new models which, to understate the obvious, are vulnerable! Such cars like the Hornby Classic Vanwalls and Maseratis, Coopers and Ferrari 156's Revell/Monogram classic sedans like the Cortinas and NSU's and soon to follow Simcas and Trabants!

There are some other classics too which are just too unstable for comfort. Ninco and MRRC Cobras, Scalextric minis and a whole host of yet to be released classic and modern sedans. Some manufacturers partly get round the problem by exaggerating the dimensions of the model. Ninco are notorious for this with a lot of their earlier touring and rally cars being a lot wider than scale.

The thing is what to do about it? With some beautiful models announced for release this year there are going to be plenty of broken hearts and cars by Xmas 2006. This will also colour the hobbyist's subconscious buying behaviour. If he's getting too many bad deals from one manufacturer or another then he will be consciously or subconsciously wary of future purchases of this brand or that.

So, what to do? The vast majority of slot hobbyists are not technically attuned to the mechanics of the hobby. Most people want to stick the model on the rails and have instant satisfaction! After all, what other hobby expenditure do we make to find we then have to spend hours researching our purchase to get a few minutes satisfaction?

The answer may well be as simple as $10.00 well spent at the local electronics hobby store!!

The main problem is that some of the new classic releases go far too fast for their size and centre of gravity! Classic examples are the Scalextric Classic F1's. The Cooper T53 and its stable mate the Ferrari 156 are veritable projectiles. Fine for scudding down the straights at breakneck speed and holding on for grim death through bend after bend. A lot of people would be happy just to have the model drive moderately fast and have the ability to deslot in corners providing the deslot impact isn't going to ram the front axle back to the drivers bum taking several dollars worth of detail with it!

There have been several after market 'cures' announced and proclaimed which are 'either / or' fixes. Down grade the motors. Fine, but that is more expense and a search and an eventual locate and retrieve exercise for the parts and then a bit of mechanical expertise to change pinions and convert! Downside is that once changed, the model is then set in that mode until changed back!

Another is a variable power supply. This is actually a lot better then the first idea but it still has a couple of drawbacks. The first is that it is quite, no, VERY expensive to purchase power supplies of this quality. (Sorry, the old train transformers just wont cut it, not enough watts!) Also for those who like to keep track of their models, the variable power supply needs to be set exactly every time you want to do racing comparisons. A variable pot. and analogue meter are not conducive to this.

The third solution would be to have some sort of switch in, switch out shunt (resistance). I think we're getting close. What is needed is a constant resistance which is the same each time you race and is the same for each lane when using multiple power supplies, and being switchable, allows the power to be switched back to normal for other racing. It's my view that the most obvious solution would be a simple circuit which switches predetermined resistances in and out of supply when needed!

On my local board track (21 metres, 2 lane) we have had this problem for a little while now and it has prevented us racing some of our more cherished models for fear they would self destruct at the drop of a hat! It doesn't need to be the landscaping that causes it, an errant car across the wrong lane will see minutely detailed parts 'pinging' their way across the scenery! Our solutions was as follows.

It was essential to reduce the wattage supplied to each lane and it was essential that this could be accomplished with minimum fuss, no screwing or unscrewing of thingies and no changing this or that and clipping it all back together. No changing of motors, and no soldering resistors in the models! easy? I should say.

The solution presented itself as this:

I purchased two 'in-line' auto fuse holders, the type which take the long glass cylinder fuses. I then purchased two differently rated resistors. One was 10 ohm 1 watt and the other was 20 ohm 1 watt. The wire ends of the resistors were curled into a loose 'pigtail' and the complete resistors and ends were slid into the fuse holders. The bayonet end cap of the fuse holders were refitted and checked to make sure the resistor pigtails were long enough to make contact. If not, they only needed a slight stretch to extend them to fit.

Next was the switch. With the other parts I purchases a DPDT (Double pole, double throw) switch. The centre terminals on both sides of the switch were connected to the track side of the wiring (positive or negative, its not that important) at the transformer connection. Next I connected one end of the auto fuse holder to one of the switch end terminals. The terminal on the opposite end of the switch had a piece of plain wire about the same length as the fuse holder connected to it. The two loose ends (fuse holder and plain wire) were then connected together at the transformer where the original supply wire was disconnected.

This then allows you to switch between a resistor circuit or a non resistor circuit literally at the flick of a switch. One minute you can be racing Trans Ams or F1’s at breakneck speed and the next you can be running Classic models at a competitive but not destructive pace.

Depending on your power supply, the value of the resistors would be trial and error. We have a couple of 14v 21 watt transformers from older Scalextric sets and we run 10 ohm resistors. The 'wall wart’ supplies may only need 5 or 8 ohm resistors for the mini motors that Hornby are now using. Another variable is your track . If you run a home circuit which is fairly fast then the reduction would be small but the average home track of about 15 metres will probably take 10 ohms or so. Once installed, a flick of the switch is all it takes.

We now enjoy racing some of the more delicate models we have purchased in recent times between the cut and thrust of F1's head to head and look forward to getting more from our hobby, Not to mention the models yet to come!

When I'm not racing slotcars,
I'm out in the back yard, burning food!!

When I win, it's because of my talent, not my car or my controller!
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