frontend schimmy

Tips and tricks about building a car. painting it a making it run smooth.
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rex craemer
Posts: 456
Joined: Thu 4. Dec 2014 09:53
Location: cologne

frontend schimmy

Post by rex craemer »

i found out somthing new. i had very bad schimmy at my 190 e. and he dont liked left lanechanges. i have seen that the right frontwheel didnt stand on the track. i installed a ring under the frontaxle to make all tyers stand exactly similar on the track. efect is, no problems with steering and complete eleminate of frontendschimmy. it drives straight like an arrow.
rex craemer
Posts: 456
Joined: Thu 4. Dec 2014 09:53
Location: cologne

Re: frontend schimmy

Post by rex craemer »

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rex craemer
Posts: 456
Joined: Thu 4. Dec 2014 09:53
Location: cologne

Re: frontend schimmy

Post by rex craemer »

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rex craemer
Posts: 456
Joined: Thu 4. Dec 2014 09:53
Location: cologne

Re: frontend schimmy

Post by rex craemer »

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Keld
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Posts: 417
Joined: Thu 13. Dec 2012 19:06
Location: Copenhagen, Denmark
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Re: frontend schimmy

Post by Keld »

About schimmy wheels, there are several reasons for this.

As rex creamer found out, this will happend when one wheel has less contact to the road, and since the cars has a straight chassis without any adjustment this can happend, and it will happend when the wheels are going to be weird down. or the chassis getting cold and hot it can bend too.

I don't know about the setup of the car, but since the car is rear wheel powered the correct setup is a little bit of toe in, since the car on high speed straight forward will push the front end and causes a little toe out, so more toe in can reduce schimmy wheels.


Due to this fact I will make my 1/24 chassis in 2 parts with springs on the screws where the are set together so I can keep all 4 wheels on the road. and I will try to make the toe adjustable on the prototype to find the right adjustment.
/Keld
Ned
Posts: 368
Joined: Sun 13. Apr 2014 01:02
Location: Sedona, AZ USA

Re: frontend schimmy

Post by Ned »

All of my cars experience frontend shimmy at high speeds. I have verified that all 4 wheels of the cars are making contact with the road. Could the shimmy (dancing wheels) be caused by too much wobble of the front wheels? Both my brand new wheels and my used wheels wobble on the stub axles. As best I can measure, the diameter of the stub axles is 0.0625”. It appears that the diameter of the hole in the hub of the wheel is about .004” bigger on average. Interestingly, the diameter of the hole is lightly bigger on the outside of the wheel than on the inside of the wheel. Perhaps the hole in the wheel is too big for the axle or alternatively the diameter of the axle is too small for the wheel. What do you think?
If excessive clearance around the front axles is part of the cause of the shimmy, do you know of any way to reduce it. Perhaps reduce the size of the hole, especially on the outside of the wheel? How? Do you think that epoxy would stick to the stub axle if the axle were sprayed with silicone before the epoxy was applied?
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