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| The first thing to do is define what a skid pad is. It's a circular layout where a car can be tested, after only making one change. The idea is to see how the change impacts the car. There is no limit to what one might change, as long as every other factor remains the same. We'll get to some testing in a little while. We made our track from four 9" sections of Model Motoring track, but any style or radius will suffice. Lay it down as tight as you can make it, and scribe a circle around the edge of the tracks, on a 1/4" piece of wood. You will cut this out, and use it as apron, and to hold the track tight. Keep something in mind. You really do not want to test on the outside, because the apron will not have the same adhesion as the track, so the apron factor is not critical. Run your tests on the inside lane. Screw it all down onto another piece of wood, of your choosing. You might also want to glue the track down. Take as much time as is necessary to make all the joints absolutely smooth. Before securing, there are a few electrical connections to deal with. First, solder jumpers to the bottom of each piece of track, and run them in parallel back to your power supply, through a steering wheel controller, or any other controller that will stay without holding it down. Make one if you are so inclined, with a resistor. Attach power taps, if you like, so that power may be supplied by attaching alligator clips. Also, install some kind of reed or light sensitive switches for timing. You need a lap timing system that will read .001 of a second, or better. Doing any less will just not give you the information you need to evaluate. I'll explain that later in this article. Now for the testing. This was very interesting, and I will now explain why a lap time is more important than what you hear the motor doing (i.e. making more rpm's). You see, what I found out was that the performance curve frequently has some flat spots. In other words, there may be a range of voltage where the car is revving faster, but not gaining lap time, because the car is spinning out. Yet, continue to add speed, and after a while, the lap times improve. There are usually two or three of these plateaus, until the car simply breaks free. We did several different tests. Bodies, tires, brushes, wheel base, etc. Anything you can think of. The results often surprised. Take for example the fact that the best time I got on the skid pad was with one of my slowest cars. No way this car is even competitive. Yet, take a race competitive car, make some changes, and if those changes improve skid pad times, it also improved track times. It is our feeling that this type of testing is very important, and every club or individual should consider building one. From now on, every test of a car or part in HO World will include a skid pad test. This type of benchmark is very good for helping to get quantitative and substantive data. | Typical Skid Pad | |||||||||||||||||||
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| Below, top to bottom: Base, and plywood cutout. groove cutout for reed switch (taped over for gluing). Ends of reed switch (solder pig tails on). | ||||||||||||||||||||
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| Left: Drill, and screw the track section together for tight fit (Lock and Joiner track). | ||||||||||||||||||||
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