Fine Tuning Your Stock AFX Cars For Performance - 3
INCHES CAN ADD UP TO MILES -- Your stock AFX cars can run better -- faster -- and your competitors may not even know why!
This is the story of AFX fine tuning:
A brand new AFX car, straight from the box, is just like an automobile fresh from a Detroit assembly line. It will run well, but performance improves as it becomes "broken-in" and can be made even better by fine-tuning. In this chapter, we'll take a look at some "fine-tuning" steps that are easy to do, yet makes a big difference when the car is on the track.
Speaking of track, consistent good performance begins with a clean track, properly wired to minimize power losses. This is the first step in fine tuning, so see the Chapter on track before you start work on your car. Note especially that the slot must be clean as well, to permit smooth running without deslotting.
The new AFX high performance track has deep slots so super speeds may be attained. All AFX cars manufactured after 1971 are fitted with reversible guide pins that snap into place. Use the deep slot blade for highest speeds on the new track, or reverse the guide and use the pin end when racing on tracks made prior to 1972. Make sure the guide runs freely in the slot and has no burrs to slow you down.
One of the easiest and yet most significant improvements you can make on your stock AFX cars is to 'run-sand' the rear tires. These are cut from sponge rubber and have high spots that cause wheel hopping and poor handling. 'Runsanding' is the only way to remove these high spots and make sure the tires are perfectly round.
The first step is to remove the body by holding the rear end with one hand and pulling the side of the body with the other. Lay the body aside, then remove the rear tires and spread a thin coat of contact cement inside both of them. Next, scrape the chrome off the rear wheel hubs and apply contact cement to the rims. replace the tires and let the cement dry for at least 30 minutes. The cement bonds the tires to the hubs so that once you true them up, they will stay.
Cement a sheet of fine sandpaper to a piece of thin wood or cardboard (such as a tablet-back). Place your car on the track (or hook it directly to the power supply), turn up the controller to 'fullbore', and touch the rear tires to the sandpaper. True up the tread surfaces, rounding the inner and outer edges a little to prevent flipping, but DON'T SAND TOO FAR or you'll reduce tire diameter to the point where the chassis drags on the track rails.
Important: Run-sand the tires first because you'll have tire dust all over the chassis and, in fine tuning, cleanliness is the watchword!
After the rear tires are trued up, check the front ones for out-of-roundness and replace them of necessary. The stock Aurora front tires are adequate as they are neither so hard that they amplify vibration nor so soft that they 'scrub' and slow you down.
In model car racing, as in any type of racing, you must get to know your machine inside and out. Practice taking it apart often enough so that you can put it together in the dark; when thew time comes that you may have to so this in a race, you'll win.
With the body removed, spin the rear tires and note that three gears revolve. Look under the rear gear and you'll see two additional ones underneath that drive the rear wheels. This is a lot of gearing for a small race car, and means plenty of drag. While the gears are made of Nylatron, a self-lubricating plastic, a tiny drop of oil in a few spots (as indicated on the chart) will reduce drag. Don't use more than a tiny drop, however, as oil spreads readily and has the bad habit of collecting dust, dirt, and fuzz. All those will only slow you down! The applicator on the Aurora oiler is too big: Use a needle or pin instead.
Before you remove the gear clamp, note carefully which color magnet goes where so you'll get them right in assembly, and remember that underneath the armature are two small, cylindrical motor brushes that will fall out. Keeping this in mind, remove the clamp and gear plate noting that the front end of the latter hooks into the chassis.
Flip the gear plate over carefully and look at the armature commutator. If you see any oil or lubricant on its surface, clean it off with tissue and hot soapy water. Polish it with very fine (600-grit) sandpaper or eraser, taking care not to damage the armature windings. Spin the armature while checking the gears and making sure they're not warped, that there's no flash or dirt on them, and that they aren't binding. Examine the motor brushes and clean these as well. Brushes and commutator must make the best possible electrical contact for maximum performance. Any dirt, fuzz, or oil between them results in poor operation.