2.4ghz cars

Tips and tricks about building a car. painting it a making it run smooth.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

Racing Regards

Kim K.
kiklo
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Re: 2.4ghz cars

Post by kiklo »


The only problem I have found so far with these are arm movement. Could have been better reach. And make sure you don't get perpendicular strain on the arm. Hence the guide on my setup.
Racing Regards

Kim K.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

The only problem I have found so far with these are arm movement. Could have been better reach. And make sure you don't get perpendicular strain on the arm. Hence the guide on my setup.
Much better : turning the servo longitudinal you get a much better servo movement.

Using 3 mm Diameter magnets, 4 and 4.5 mm long : to adjust force (4 all together ) I get a very crisp steering.
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Kim K.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

Anyone interested to test?

I'll send you a setup if you cover postage and a few $€£ for the work. ca. 6 $€£ total..
You will be able to use parts from your old car except the magnets and servo and a piece of Mag-wire for the servo connection.
Just PM me.
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Kim K.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

Hmmm.

This is about as short I can manage with std. battery. Should have been 2 mm shorter to use with the Mini.
Looks like another shorter battery is the only option.
And yes I have ditched reverse for the receiver/ESC Frsky combo.

Chassis measures 32mm wide by 90mm. Wheelbase a-a 70mm.
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Kim K.
Ned
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Re: 2.4ghz cars

Post by Ned »

Good job Kim! Very compact design.
Ned
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Re: 2.4ghz cars

Post by Ned »

Kim, you said "This is about as short I can manage with std. battery. Should have been 2mm shorter to use with the Mini."
I may have an idea that might shave 2mm off the wheelbase. What is the distance between the front axle and the blue block of plastic holding the 2 magnets by the pivot point of the guide/tiller arm? Need to know the distance when measured from the centerline of the axle to the face of the blue block that is farthest from the axle. I might be able to reduce the space occupied by the steering linkage.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

Hi Ned

Center of axle to end of magnet pivot arm is 22.8 mm. From the pivot center it is 12 mm.
I have already narrowed the steering linkage with 15-16 mm. so there i less room to play with.

The problem is if I try to cut another 2 mm. off the moving magnet of the linkage get to close to the battery.

So the only way is if one can shorten the whole linkage so the magnet get 2-3 mm towards the front. That is a hard task.

I have tried several arrangements with 2 magnets wide wise on the pivot and one on the connecting steering arm. No reason why it should work as good, but I have not managed.
Racing Regards

Kim K.
Ned
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Re: 2.4ghz cars

Post by Ned »

I like your idea of running the centerline of the battery and the motor perpendicular to the rear axle.
You might want to consider this Rx & ESC combo which is currently out of stock. It has reverse and works with Flysky transmitters. Not sure if the voltage would work.
https://www.banggood.com/SINOHOBBY-Mini ... rehouse=CN

I don’t understand why you are using 4 magnets on the guide arm toward the back of the chassis. They take up a lot of space.
Why not use a HK-5320 servo between the front wheels and then use steering knuckles (stub axles carriers) and a tie rod like in the original magracer. That’s the approach I’m using in a chassis I’m designing. The distance between the centerline of the front axles and the aft side of the tie rod is only 17.7mm. That’s 5.1 less than the 22.8mm you mention. Then you could easily shorten the WB by 2mm.
kiklo
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Re: 2.4ghz cars

Post by kiklo »

Ned wrote:I Not sure if the voltage would work.
https://www.banggood.com/SINOHOBBY-Mini ... rehouse=CN
7.4 V probably not going to work. And 40 by 20 mm is not small.

Will be interesting to have a look at your design when ready. (could not quite get the grip of your design, my bad English.)

I can see another problem with the mini : the wheel size. Will not touch ground with the std. chassis.
Racing Regards

Kim K.
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