Tired of one size fits all "paper trick"? Try some math!

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toyotatime

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Arrma RC's
This article is very technical but the formulas and principles behind it are fantastic
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http://khkgears.net/gear-knowledge/abcs-gears-b/basic-gear-terminology-calculation/

If you have a good magnetic base dial indicator

And a set of calipers

you can do this and have your mesh set mathematically correct to your tooth count/modulus, by setting the center to center distance.

Instead of using the one size fits all "just jam some notebook paper" in there thing. And potentially adding running cost to your driveline.

There are also formulas and tables for helical cut ring and pinion...for your diffs etc.
 
Oh and once you measure and calculate, you will get a backlash measurement you can quickly verify and set with a dial indicator.

Not knocking the paper trick, I would do this in the field if I didn't have my tools but I ALWAYS have my tools so...no more paper lol
 
Nice theory. Might be possible with the hot racing motor mount. With the stock one though, not happening.
 
Nice theory. Might be possible with the hot racing motor mount. With the stock one though, not happening.

There was another formula i found that didn't use shaft centerline....it used the number of teeth on drive and driven and your modulus.

I misplaced the link but my 13t pinion and stock kraton spur ended up being nine thou or .009" backlash.

You can easily get a dial indicator on a spur gear tooth on the battery side and measure your lash...going centerline to centerline would be impossible without some disassembly but you would only have to do it once to take measurements on a particular gear set.
 
Gears wear so you'd have to do it pretty often... Too silly for my taste.

This is for measuring and setting the correct backlash on new gears on a per application basis.

Because depending on how many teeth each gear has (circumference) and the spacing and angles on these teeth (modulus) will determine proper lash.

You could use the paper trick which ends up being .003-.005"....and that may be fine.

I wouldn't take my driveline apart to make a adjustment on a worn gear set.

when most people screw up pinions and spurs is when they're starting out...i know I did.

In my line of work guessing means lots of people and animals die, so I'm just not used to accepting a one size fits all solution.
 
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