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F_Zero
2008.05.13, 08:35 AM
Something I made with photoshop. It features 2 Li-Ions, 130 Motor, Electronics, regular servo and full independent suspension.

To adjust gearing, if I could make the car real, would simple have different rear diffs, that are spaced further away from the center of the car because of the larger pinion gears.

I thought I would post it because it is a really good idea, maybe some- body will make it.

cowboysir
2008.05.13, 09:26 AM
Looks interesting but you need to consider your drive ratio...by running the pinion gear stright to the differential you remove an important aspect of the final running gear. The spur gear that would normally run in between the two elements shown is integral for a good running driveline, giving the motor a final drive ratio that is controllable.

Otherwise, it looks like a well thought out platform....a blend of MR02, AWD and a bit of gen1 xmod.;)

color01
2008.05.13, 11:07 AM
Aside from the gear ratio problem that Cowboy pointed out, it is a pretty good layout. The other problem I'd like to mention is motor torque, when you slam down on the throttle the torque the motor produces will twist the chassis and put more load on the right-side wheels. This could be an issue when running; both Gen 1 Xmods and Mini-Z AWD's are slightly affected by it.

You may also have trouble fitting Mini-Z bodies on the chassis, the Li-ions are right where the side body clips usually go. If you use body posts then of course this isn't a problem. :)

Programmers
2008.05.13, 11:30 AM
My modified MR02 pulled to the right under immense acceleration.

color01
2008.05.13, 11:33 AM
So did my MRCG prototype until I fixed the tweak problem. :) I didn't have much time to sit and work on the MA010 but I remember on the Gen 1 Xmod I preloaded the rear springs differently to take care of the on-power tweak. I believe similar things are done for the MA010, M18's, and shaft-driven touring cars.

F_Zero
2008.05.14, 11:55 AM
Here are some new pics.

cowboysir, this is the same as any RWD kit. The pinion gear is just set vertical to the rear differential. Like I said.. when you add larger pinions, you just need to move the main diff away from the center of the car to make room for the large pinion gear.

For a prototype, I would probally make the rear diff a solid axle, like a spool with spacers that fit inside the spur gear. They are layed in the center, so when you use a larger gear ratio, you take apart a 2-peice designed diff and switch flip spacers inside it.

It would be too complicated to make a full ball diff first off, I think a 2-peice design, 2 cup joints, 1 spur gear and spacers would be the easiest to do. I see you people talking about how a Mini-Z will slide to the right or left because of the located of the diff and pinion gear. There are a couple of ways I could fix this problem, even on a stock Mini-Z...

1. Make the pinion teeth shorter than the rear diffs. This reduces a lot of rolling vibration and Center of Gravity. This helps for Belt designs, as it will reduce belt vibrations.

2. Change the direction of the spur gears teeth. On this custom RWD kit, you could try 3 different prototypes. The first, a regular design with the teeth like a pyramid, going in same directions. The 2nd prototype, the teeth are going in one direction, and for the final protoype, the teeth go in the opposite direction of the 2nd prototype. Like a One-Way one the front of a RC car.

With it you could make another set of prototypes, al the same with a lower amount of teeth touching the main spur gear.

I'll make a couple of pictures in the next week or so, just so you understand what I'm telling.


Anyways, stuff you could use for a protoype. And I don't have a name for the car, I call it the R2 for the the 2 Li-Ions, or the SneakR, for the Low COG layout and Li-Ions.

A.

Mini-Z AWD Rear Bulkheads & Suspension or aftermarked alloy Mini-Z AWD Bulkheads or Atomic Racing Rear AWD Suspension Kit

B.

Xmods Stock Kit 130 Motor Mounts or GPM Alloy Mounts.

C.

TGR Sinister, for the front design with the standard RC servo mount.

D.

2.4GHZ Mini-z Electronics.

E.

Finally, A Custom main carbon fiber lower chassis plate to put it all together.

New Pics:

eztuner12
2008.05.14, 09:09 PM
It would be nice to have an all around independent suspension with swinging upper and lower arms.
I have made my self many times the same question, why it always has to be a T-plate system and never a swing arm including the AWD. I see Xmods Evo chassis is very well design with great weight distribution, but still you can’t set-up the suspension geometry, very high CG and terrible electronics.
Cheers

F_Zero
2008.05.15, 02:37 PM
The Xmods are ok, I didn't like any of them to tell you the truth. The Evo I think that was it, had to much plastic and I didn't like the batteries hagging underneath.

Anyways, I got a new Prototype. Check out the pics, I call it the F-Zero, may change the name, and I might make a few more photos.

I have never owned a Mini-Z, I would like to own one, but after the IRS with my family, I can't afford anything and with SSI and all. If I could I would deffinitly own a MR-02 and MA-010 with titanium, cf, ceramic, you name it. Probally cost aroudn $3000 for just the 2.

I used to own some RC cars, maybe I will post some stuff somewhere. :)

If anyone wants to make a prototype, just ask and you will receive.

For this version, it supports the SAS, but I need to redesign that system. The motor, I might pull into the rear more, let it hang a little. With out the servo the car is perfectly balanced, which I find good.

I need to do side views too.

F_Zero
2008.05.16, 02:20 PM
New version. I just added the normal rear alloy suspension. This drawing has the motor mounts adjustable, but I think I am going to do another version that is a really different with the motor and its mounts.

Comments are welcomed.

F_Zero
2008.05.19, 01:30 PM
Thanks. Do you have a pic of those cells?

I have a few more versions of this RWD setup. One is taken from another design on the net. The guy that created the pocket-knife. I will probally talk to him soon too.

Since I don't own a Mini-Z, the scale is off, so all drawings are basic works of art. But trust me I have owned my fair share of RC stuff too.

I will post the new versions tommorow Tuesday, they look much better than anything posted yet I guess.

For the pinion gear, I am worried the direct fit of the pinion gear to the rear ball diff will spin to much, cause a less active diff. I think if the rear diff is compressed more as a stock setup, it will be fine. I also have a new ball diff I designed that I am sure I never seen before. I need to start making it too.

F_Zero
2008.05.20, 06:31 PM
Here is another version, not the Pocket-Knife one though...

I am going to see if I can find some Brick Cells, they used them for the 1/18 Micro RS4. I wonder about the size... Maybe I will make a 4-cell chassis too.

color01
2008.05.28, 05:34 PM
An XSpeed will be pretty insane on lithiums, especially since you'll be tempted to gear it to the moon, and when that happens, it'll be ballistic. :D A PN Stock motor (70t) is a good match for lithium power, and will offer you a decent gearing range given your drivetrain layout. The way your chassis is designed, the final drive ratio is innately high enough to compensate for the high voltage and high-turn motor. ;)