by
Daniel J. Dyke
In my younger days Jim Hall of Chaparral fame was one of my heroes, but not as a driver. It was his engineering vision that attracted me more than anything else to him as a person. His vision included objective data acquisition and testing to make a better race car. The testing was done both on his personal raceway (Rattlesnake Raceway) and on a skidpad. The results were significant in that his cars were better at every race than the one before and so he became a legend.
One of his tools was the skidpad, but what is a skidpad? It is a an oval or circular test track that has all turns of a constant radius. On this track speed is gradually and incrementally increased until the car spins out or starts losing speed from sliding. This objectively tests how changes in a car's design affect cornering speed.
Most slot racers have their own racetrack, but few have a skidpad. They are easy and cheap to make and should be a part of a serious slot racer's workshop. The skills required are minimal. Let me take you through a step by step construction process that is adaptable to any track type.
Depending on one's skills with a soldering iron determines how he will construct his track. The choices are simple, one can either make a small oval or just a circular track.
NINCO SKIDPADS
CUSTOM SKIDPADS
Ninco users have the easiest task before them. There is nothing to solder or modify, because all the parts are readily available as off the shelf items. One begins by buying a Ninco track from the Speedway series ( Ninco Speedway Set, Item # NIN20112). Personally, I wanted the Ninco Cobras and so for just a few dollars more than two Cobras I got a set. I now had a small oval, two controllers, a power pack, and two Cobras. I was then faced with the problem of what to do with the track The set included eight turns, two regular straights, a power connection track and two half straights which are also the adapters to connect Ninco track to SCX/Scalextric track. This was the genesis of my skidpad. From this assortment of track one keeps the turns and the power connection straight. The rest of the track can be integrated into your main track or sold to recover some of the investment.
The second item one buys is the Pole Position Lap Counter / Timer (Item # NIN10403) which will become the heart of the system. The unit includes one regular half straight, a half straight that serves as the detector strip, and the timer unit which measures down to a thousandth of a second. This level of accuracy is very necessary as the track is so short the cheaper timers such as the Carrera ones will give misleading results as they go only down to .1 seconds. The $110 price tag sounds like a lot, but remember that the timer/counter can be quickly and easily moved to your main track. There it will become your opponent when you can't find a human opponent to humiliate you.
Step #1: Basically one makes a small oval with the timer, power supply and controllers installed as in figure 1.
Figure 1
Since this is an integral part of my workshop and there is limited space, I did not want have to assembled and then dissemble the track when space was needed for another tool such as a scroll saw. Taking a suggestion from a friend, I mounted the track on a small board and so when it is not in use the controller and power pack are unplugged and then track is leaned against the wall or moved out of the way.
You now have a sjidpad and can start playing Jim Hall.
CUSTOM SKIDPADS / MODIFICATIONS
WARNING!
Some of these modifications may void your warranty
or damage your equipment if not performed carefully.
You should proceed at your own risk.
1) Reducing the Track Size/Using Another
Brand of Track
2) Alternatives to the Ninco Pole Position
Timer
3) Multiple Skidpads for the Space
of One
4) Options to Enhance the Track
5) Tests to Perform
6) Results
Obviously not all people use Ninco track. Many race on multiple track surfaces. Others may not have the finances for the Ninco timer. Some may not want a track this big. There are solutions for all problems if one does a little research and tries to think through each situation.
1) Reducing the Track Size/Using Another Brand of Track
a) Hard wiring the power cables and controller to a curve or a short straight (figure 2) cuts out the need for the power straight. One moves the second half straight to the place where the power track was removed. This route is the one to travel if you are timid about doing the next step. This is the layout of my skidpad.2) Alternatives to the Ninco Pole Position Timer
Figure 2b) Move the sensors from the Ninco track to a curved section of track (figure 3). If you study the sensor track carefully, you will see that they can be moved to a curve or adapted to other brands such as Carrera. I have not done this, but conceptually it should work, but I must confess as to being a coward on this type of operation. The one area to check, if you decide to try it, will be to see if the slot depth is adequate. The Ninco sending and receiving units are positioned on opposite sides of the slot and if the slot depth is not adequate a false signal could result. I personally would not do this, but the choice and responsibilty belong to you.
Figure 3
a) A quick search of the web revealed many commercial, shareware and freeware programs.3) Multiple Skidpads for the Space of One1. http://web.inter.nl.net/users/dekloet/b) The one I am most interested in at the present is #6 by Gregory Braun, because it runs under Windows (95/98/ME/NT/2000/XP) and includes easy to understand instructions for making the sensor track. It also has instructions for sensors that will work with Trackmate (#4) and for the VRS system (#3). If you decide you do not like his software you can easily adapt the hardware with little or no work to the other timing software.
2. http://www.vmbollig.de/Hometrack/hometrack.htm
3. http://www.i2mnet.com
4. http://www.infoserve.net/oss/slotcar/index.htm
5. http://members.aol.com/dlel/slot_master/welcome.htm
6. http://www.gregorybraun.com/
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7. Scalextric RMS software when it becomes available
Since many of us race on multiple track types and some of us actually have several tracks, it is beneficial to have multiple skidpads. Currently I am interested in building multiple skid pads for Carrera, old Scalextric, and Scalextric Sport track. How does one do this? They can be built and stored in multiple ways.
a) Types4) Options to Enhance the Track1. Each is put on a separate board and put on the wall like a picture.b) Sharing Peripherals: If you make your own connectors for your controllers/rheostat and power hookup, then make them all the same so you do not need multiple power supplies and controllers.
2. Drawers the size of the largest skidpad are made for the workbench and are pulled out as needed.
a) Replace the controller with the most sensitive rheostat that can be found.5) Tests to Perform:
b) Replace the controller and power supply with an HO train transformer with a built in rheostat to save space. These are very expensive and are not worth the expense to me, but some are very nice.
c) Build aprons around the outside lane to permit sliding.
a) Does sliding help or hinder speed?6) Results: I recently tested the Ninco F-1 Ferrari against the Scalextric Sport Williams (Montoya). The same tires were on both cars and neither had magnets. Each car did several hundred laps. The Ninco turned a best of 1.101 and the Williams a 1.100. Conclusion? There is no real difference between the cars on a skidpad when equipped with the same tires. What is interesting is that on the 45' full track the Ninco turned a 5.892 and the Scalextric turned a 6.006. The difference was that the Ninco could take the hairpin much better. The closeness of these numbers demonstrates why a person wants a timer that goes down to .001 seconds.
b) Which tire works best on your surface?
c) Would painting a surface with a different texture help or hinder performance? Choose one section and paint it. Put it at the place where the cars usually come off. If the times are better then you may want to paint the rest of your track. If they get worse then you probably don't want to do this unless you wish to make a treacherous corner.
d) Is weight or magnetic placement really helping?
e) Are the front tires hurting performance? Run with and without the front tires and then modify their position.
The tool is only useful to some people and measures only certain things, but for me it answers many nagging questions and I find it useful and helpful.
Email comments and suggestions to dan.dyke@goodnews.net.