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Old 06-15-2003, 03:32 AM
Hooters Driver Hooters Driver is offline
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Join Date: May 2003
Posts: 59
These are some of my thoughts on building a custom mini-x chassis:

Since the mini-x has 4 wheel independent suspension the chassis should be as stiff as possible. You want the suspension to do the work, not the chassis.

Another reason for building a stiff chassis is due to the long motor shaft. In my opinion, chassis flex is one of the reasons the stock mini-x motor runs so hot.

The other reason the motor runs hot is due to the front dog bones binding up. This problem definitely should be addressed if you want maximum performance from your mini-x. I've worked on this quite a lot and it's a very fine line between free rotation throughout the entire supension travel and having the dog bones falling out.

In my opinion, the whole purpose of building a custom cf chassis is to save weight. With that in mind it seems to me that running 1000 MAH batteries would be counter-productive. To save weight one thing you might consider is running lithium-ion or lithium-poly batteries. That way you get the high MAH rating and still keep the weight down. The challenge with lithium batteries is finding a large MAH battery narrow enough to fit between the motor shaft and the body.

Since batteries are the heaviest component on the car they should definitely be placed as low as possible. If you run out of room and have to stack components then the receiver should be the first thing to go up top, next would be the speed control. If at all possible the batteries and motor should be the lowest components on the car.

Another weight consideration is where you place the heavy components. I race circle-track cars and we practice the rule of the 3 Ls during car construction - low, light, & left. Unless you run your mini-x on an oval the left may not apply to your car but you should still consider your track when building the car. If you run counter-clockwise (more left hand turns) the heavy components (batteries and motor) should be on the left side of the chassis. If you run clockwise the arrangement should be just the opposite.

One final thing to consider is the motor. Because its shaft is placed parallel to the centerline of the car, the torque of the motor causes the car to be loose when turning right and tight when turning left. If you use shaft drive like the dtm it will allow you to mount the motor perpendicular to the cars centerline (similar to a mini-z) which will eliminate this bad handling characteristic. Depending on which direction you spin the motor it can also affect weight transfer which can help tune the car for your track.

I hope you find some of these tips helpful or at least thought provoking. Good luck on your custom mini-x.

Last edited by Hooters Driver; 06-15-2003 at 06:41 PM.
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