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Question : What are the important things to watch for in slot car gears?

If one builds a metal chassis with an anglewinder, final gear mesh can be adjusted by sliding the driven gear from side to side on the axle because this effectively changes the center-to- center distance of the motor shaft and axle.  If the design is a sidewinder, and the motor is soldered in, you'd better get it right.  Anyone have any tricks?

Response : I always solder my motors in, whether it is an anglewinder or sidewinder and always adjust the gear mesh by moving the motor, rather than the gear.  Make the motor-box about a millimeter wider than the bottom of the motor, each side of the center-line of the armature shaft, and you have enough space to move the motor forward or backwards.  You can bridge any gap between the brace and the motor with solder.   Another trick is to use Sonic gears.  They make a range of 64 pitch and 8O pitch  gears, specially for 1/32nd cars, which all have the same diameter, allowing you to change gear ratios with having to adjust anything.  From memory, the gears are all 15mm in diameter and in 64 pitch they come with 35,36,37,38 and 39 teeth.

Correction : I should have mentioned that SLOT.IT employs the same principle, which is great for Scalextric, Fly, Ninco, etc. cars and can of course also be used for scratch built cars.  The SLOT.IT Pro Axle sidewinder gears are made from an aluminum alloy.  They are 48 pitch and are available in 34, 36 and 38 tooth. All three gears have the same external diameter, making it possible to change gear ratio without moving the motor, which so far has not been possible on plastic cars.

The SLOT.IT gears are a direct replacement for the plastic gears which come with the home-set cars and for best results should be used along with SLOT.IT pinions, rear axle and bearings.  They mesh superbly.  

I see, in these parallel threads, a lot of ideas and outright statements.  Some are theory, some practical, and usually, no differentiation is made.  I have, however, chased a lot of bad ideas, gone down blind alleys because of a Theory that did not account for all the variables in place.  Since then, I have developed an approach when going to a new track (those that know me know that I like to go visit some new track).  The first thing I do is check the Contacts.  First.  Talking about the differences between Scalextric and Revell, the first thing you will notice is that Revell is largely a flush steel rail, and Scalextric is slightly raised.  This changes EVERYTHING.  Remember the bit where Pete and I chant that slot cars are a TRIPOD defined by the guide and the rear tires.... This is a real case in point.  It is common for someone with a car that works well on Scalextric, to be tricky on Revell. The Revell will feel slippery and the car will seem to suddenly go off nose first with little warning.  Why ?  Well, what is happening is that the car which was riding on the guide, is now being dropped slightly and the front wheels are carrying the car.  The contact will often be flaky, and the driver pulling the trigger and not getting the expected response will sub-consciously adjust and give a little more ... too much and off nose first !  Going to a routed track produces a similar set of problems with the guide.  Most modern routed tracks have braid slightly depressed, usually .025 inch, but I have seen as little as .010" and as
much as .040".  Anyway, this recessed braid reduces track maintenance.  On Jim HTs famous magnetic braid tracks (what a neat idea !),  this means that the magni-traction will be slightly reduced from a flush rail Revell, or a raised Scalextric.  Anyway, older routed commercially made tracks will be flush, being another variable.  When I go to the Vegas convention, one thing I have to do is put a spacer on my guides depending which sort of track I have run on recently.  Being that I have some cars that I have been running for decades, even my collectibles have screw mounted guides with plug in braid to make it easy for me to change the guide set up from track to track.

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