Porsche 42056 4 wheel Steering Solution

[xenos]

Hi Lego fans,

I'm close to finally completing my second build of the Lego Porsche and was interested to know if anyone has developed 4 wheel steering for this set? I am close to a prototype working solution but still need a few free weekends before i can fully validate it (need more parts)

If anyone has developed or prototyped any solutions please share them here. I will be uploading my build in the future (hopefully not to many weeks away).

My project background:

I purchased the set when it was first released, but held fire on building it, given the numerous issues the Lego community identified with the build. Fast-forward a year and a bit and some of the work done by this community just blew me away. ...and with the release of the community driven Errata compiled by @Didumos69 and the subsequent instructions by @jb70, I had no more excuses to delay building the set. My first build was as per jb70's instructions with the addition of Didumos69's modified steering module as incorporated by @Kumbbl and @DayWalker elegant gear change sequence mod. I also made one or two further minor corrections and robustness improvements and lastly added Kumbbl's minor body mod of adding a small panel below the headlights. Subsequently i marked up jb70's pdf with the additional changes mentioned above to create a new set of instructions (i don't have the skills to create Lego instructions, so just used pictures to show the changes in any steps).

My Prototype 4 wheel steering mod: (to be updated over the coming weeks - target completion and write-up: 15th Oct)

My starting point is the build as described above. After completing the first build and drooling over the amazing improved and additional functionality, I found myself feeling really guilty! The community had put in so much effort in turning this set from a real let down to an amazing build. What had i contributed - nothing!. In addition, (as i love my cars - go figure!),  I had a growing irritation with the set day by day, as it did not have a key feature of the real car - 4 wheel steering. See this excellent video demonstrating the 4 wheel drive system on the actual car.

Anyway, using some of the design principles in the 8880 set, i developed the prototype design. A key goal of the design has been to try and reuse some of the left over parts of the original set but where functionality is being compromised, new parts had to be introduced. The development is split into 4 parts:

1. Front to Rear Steering Transfer Mechanism

This mechanism is designed to fit Didumos69's modified steering module as incorporated by Kumbbl. See picture below for a view of the Transfer Mechanism which also shows part of the Rear Steering Path.

2. Rear Steering Drive Path

I've managed to hide the drive path behind the central segment of the car which is covered by black curved panels. This keeps the solution neat and hidden away, The remainder of the mechanism is shown below including the rear axle steering rack.

Rear Axle Re-design

The largest challenge turned out to be the rear axle re-design. The forward suspension strut has to be re-located as it interferes with the steering link and so i decided to move both the forward and rear struts to the top. This is probably the most controversial change, but i expect it will look very good on the car as it will be visible through the rear windscreen, when the body is mounted.

Body Changes

For future update

That's all for now folks. I will post more information once i have the correct parts to commence the second build.

Edited September 10, 2017 by xenos

[xenos]

After tinkering away during September and finally having the parts, i managed to rebuild the Porsche with 4 wheel steering, only to find there was way too much movement in the steering system at the rear and the suspension was not strong enough to support the ever increasing weight of the model. After another iteration or two i finally have a version i am happy with. See the final design in the video posted at the link below:

 

 

[Mechbuilds]

This is great work! 

[LifeIsLego]

Could you make a tutorial?