Mighty Wedge

[That_LEGO_Guy]

After getting my hands on 2 dragster tires and 2 of those new buggy motors clones I wanted to try something simple and fast. As the cable is attached I need to reverse 1 motor, ether by a switch or each motor has its own channel but the power gets cut after seconds if on a single receiver. A little better if a receiver for each motor but it only runs if each motor has its own receiver and battery box.

I initially made an independent rear with 2 of the 4L diffs with their 16tooth ends meshing going to 2 drive axles ether side meeting at portal hubs with 2 16 tooth gears, splitting the load from the motors at every step and hopefully surviving. but it ended up being way too wide, even with the diff side universal joints directly in the casing, only supported by the structure around the axle hole( this was surprisingly secure).

So direct drive seemed the only way, with the motors being swingarms but I wanted some amount of uniqueness to it and to slow it down so mounted a 2 speed gearbox to each motor eliminating all uni joints. 1:1 on the slow output and 9:1 on the fast output

but needed a way to actuate the gear ring remotely, an m-motor on each gearbox would be too bulky and couldn't have a gear train that would rotate as the suspension moved. If only I had some flexSystem.

the next best thing is Pneumatics. ether an autovalve( pump and valve from one motor) or a self regulating pump with a valve. Thats a lot of bulk for a single feature though. so Pneumatic suspension, will only be manual as the drive is 2 IR channels(and 2 receivers), Steering and gear change is another 2 IR channels. the pump is on the opposite BB to the steering.

desk driving :https://youtu.be/sMoC7r0YC-M

The front hub's top mount is offset by 1 making the steering axis inclined like on real cars, the effect is probably negligible at this scale. the steering is also really tight.

With simple off the table now I still want it to be fast so the body work will need to be basic, like old technic flex axles makinc simple shapes. like this:

With a little of another concept car the toyota RV2 with the wagon rear that folds out to a tent is my kind of crazy, ridiculous and practical.

How is sits now, with the body sketch I did to try and guide the scale. And all the pneumatic stuff just sitting on top. The large pneumatic rams are too strong to be the 'springs' will need to change the linkage or buy some small rams to swap.

Edited February 2, 2021 by That_LEGO_Guy
fix vid

[Woodstock pl]

I would highly recommend not having any gears on the rear axle, as this creates much friction. If I’m correct, you are using two double AA battery packs? If so, these are very heave and will reduce your over all achieved speed. I would recommend getting one or two buwizz 2.0 batteries. As they have twice the power as LEGO batteries, which is more the reason to remove the gears on the rear axle, or at least use wd40 on them to keep them from melting! This is a good concept, but I’m not sure how well it will work. One last thing, definitely lessen the steering angle, otherwise it will constantly roll over. Wish you luck