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Old 01-17-2010, 04:10 PM   #1
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Default Possible electronic layouts for upcoming project

I'm about to start a new shaft drive touring car project. I posted awhile ago with one layout but after more brain storming I have come up with a couple other electronic layouts for this project. I was wondering if I could please get your opinion on which you think would be the best. I didn't label the different electronic components but it should be pretty obvious. All of these layouts are pretty close to 50/50 front and back balance and close to even side to side.

#1.This first one would be the easiest layout and would have the servo in a regular position. But this would push the rx and esc to the outside.


#2 I really like this next one because it would allow for a very slim chassis and lays out the components nicely. The servo would be in front of the front diff and facing the rear it would have a servo saver on it like 1/12th steering.Unfortunately long motor wires would have to be used. But the esc could be moved to rear so long wires wouldn't be needed


#3 This is one of the only ways I was able to fit a stick pack in the center. This would be alittle bit difficult becuase I would have to make a two part center driveshaft. I do like how I could use a stick pack with it but I'm afraid it might have a hard time transitioning in the corners. The servo would be in front of the front diff like the layout above.


Please let me know which one you like the best and think would perform best. Also if you guys have any other ideas for innovative/different shaft drive layouts please let me know. I'm all ears.
Thanks
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Old 01-17-2010, 04:26 PM   #2
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First of all. I like the idea of people trying to develop their own car But why a car with shaft drive, most manufacturers switched to belt driven cars, because it makes the handling better.

#1.
Best one of your pictures, but how about turning the servo 90 degrees, with the receiver on the outside end, and between the battery and the servo/receiver the speedo. This way you can keep the weight as much to the centerline as possible. and making the car pretty narrow. Downside, especially when using lipo is that there is a lot of weight in the front of the car, making the car understeered.

#2
You want to have the receiver underneath the shaft?? This means both the shaft and the diffs for it should be in a high position, and higher your weight means a high center of gravity, which doesn't improve the handling of the car. Also this car would be very under steered, because there is too much weight on the front half of the car. Always try to keep the ratio 45% of the weight in the front, 55% of the weight in the rear. Also the servo in front of the diff will be bad for handling, always keep the weight behind the front wheels and in front of the rear wheels for good handling. Not to mention it would be really difficult with the wiring of the car (the servo wires have to go across the front diff, long motor wires as you mentioned yourself)

#3
Somewhat similair to the Losi (except for the servo), but like picture 2, there is a lot of weight in the front, especially when racing Lipo. Also here the wiring would become really difficult, because the receiver and servo are on the other side. And just like in picture 2, the servo all out in front of the diff will have a bad influence on the handling.

For a good weight balance try to get something close to this:
LR: 27,5% LF:22,5%
RR: 27,5% RF:22,5%

Also I think a belt driven car would work out better.

But most important, when you have doing it, keep on going. And keep us informed on your updates.
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Old 01-17-2010, 04:32 PM   #3
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How do you plan to get the shaft high enough to clear the lipo's?. Also you need to realize its just as important to compress the weight distribution from front to rear as well as left to right. If all that was important was having a low polar weight distribution, the losi and TM would be winning everything.
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Old 01-17-2010, 05:32 PM   #4
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What about moving the motor foward some and put the battery on the other side of it standing on it side. It will stand tall but all the weight will be very close to center. I did this to a Tc3 years ago and it made the front to rear weight transfer better and the side to side a litter slower. Reacted faster side to side.

Just a thought.
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Old 01-18-2010, 02:14 AM   #5
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I like the idea! Keep it up. but like others said, belt driven cars is probably better becuse with belt driven cars you get more chassie flex and lower weight. Not that you are bad at designing offcourse Looks like you worked this up very good!

but the 50/50 weight distrubution sound good, becuse a beginner can faster get to know the car and the car will handle exactly how you like. put som weights here and there and it should go as you like


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Old 01-18-2010, 02:41 AM   #6
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Quote:
Originally Posted by Joe Maxey View Post
What about moving the motor foward some and put the battery on the other side of it standing on it side. It will stand tall but all the weight will be very close to center. I did this to a Tc3 years ago and it made the front to rear weight transfer better and the side to side a litter slower. Reacted faster side to side.

Just a thought.
It's not only about getting the weight to the middle, but also keeping your center of gravity as low as possible. The higher your center of gravity is the more trouble you will have finding a good setup. Also the problem of shifting the motor more forward as that there already is too much weight in the front.

Quote:
Originally Posted by Andy63 View Post
I like the idea! Keep it up. but like others said, belt driven cars is probably better becuse with belt driven cars you get more chassie flex and lower weight. Not that you are bad at designing offcourse Looks like you worked this up very good!

but the 50/50 weight distrubution sound good, becuse a beginner can faster get to know the car and the car will handle exactly how you like. put som weights here and there and it should go as you like
50/50 will make the car feel really under steered. And you want a car that feels neutral. The best weight distribution is 55% of the weight in the rear and 45% of the weight in the front (for a steady good controllable car). And when you want to make a very aggressive car you can go to 60-40.. But you should always try to stay within these limits.
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