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Old 04-16-2012, 10:59 PM   #2020
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Join Date: Aug 2010
Location: Union City, CA
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Originally Posted by Oleg Babich View Post
Some recommendation for current gears:
1. Reducing of clearance between G01 and G02 gears by means of ~0.2mm grinding of AM13 face that connects to AM02 part.
Use SB3x5 screw with thread lock for fine adjustment of gears clearance ( p.16 of the Instruction).
For what it's worth, and to save others time and effort, I took off about ~0.2mm as described above. While it did help fix the gear lash issue, along with shimming G02 forward, it had the negative side effect of moving G01 too far towards the center of the car, and now am13 blocks the center shaft from being installed.

To get around this, I've shimmed it back out about 0.1mm, and took about 0.2mm off of am13 where G01/ST06 mounts (now at ~2.8mm). The gear lash is now near zero, and significantly quieter (on the bench). Another interesting thing is that spinning the gears backwards they are nearly inaudible. So I think if the curve in the gears were the other direction it would go quite a ways towards minimizing noise. The real key to getting it quiet is getting as much of the lash out as possible, while at the same time ensuring the gears line up with each other. If G02 is shimmed forward too far or not far enough it'll cause the corner right angle to be off. Hard to explain, but below the vertical bar represents G01 and horizonal underscores and hyphens represent G02 while looking from above. Even a .1mm difference can make a sizable change in noise.

|____  <-- correct

|----- <-- not correct
NOW, the spur gear is moved far enough towards the center of the chassis that the spur gear nearly hits the chassis, so I've opened up that hole just a little bit.

Another interesting thing that I came across is that instead of using a button head into ST06, I've used a countersunk screw (like SF3x5) and you can tighten it all the way down without needing lock tight. Nearly no slop in the gear, spins free and no need for shimming up a crush collar inside G01.
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