I know one good thing about tatra susp. It's very easy to build, really. It's very similar and easier than simple independient suspension, and simple independient suspension isn't good at TT. Best in TT are axels, but it's hard to build, and tatra-susp. works like axle

I just built this thing and see a potential problem. The version i built was studded and don't have wheel axles since they aren't needed for testing. It's no beauty but i think it works. Anyways the problem is that the axle connected to the right side of the model as seen in this post will not be connected to the motor unless the diff is locked. This means that at any given time only half of the total wheels of the model is driving while the other are coasting. Or is it different while driving? I didn't finish it, just the 2 axles. Then i drove it by turning the upper axle. The one that power comes from before it is transferred to 2 lower axles, one connected to a diff and then a wheel and the other directly driving a wheel. Holding the axle on the diff side allowed to axle to turn but holding the axle on the left didn't since it was directly connected to the "motor".

So is my testing method flawed? Try building this and see for yourselves. It's not difficult making the main functions You don't need to add wheel axles, just the gears that would drive them. Rockbrick you made something that while it has the diff in a different place i think does the job anyway. That itself proves have many ways one can build this diff system and still succeed. Also thanks for the links to the hotrod.

OK i just added wheel axles and wheels to it but no difference in behavior. Only one wheel is driven when the diff is unlocked. That being said,it did seem to behave in a similar way to the first diff i made that Allanp also made a version of but non of those designs would work properly or for that matter as nicely as this. I don't know if losing drive on half the wheels is really bad, i'll await further comments on that. But i do know that the design is as close to a true Tatra diff that any Lego version will have and it is rather easy to build too.

BTW don't build it studded. I ended up having to remove suspension travel in order to fit the wheel axles and their gears. You need all the room in that area that can be and studded wont let you do that. If all you want to do is test the diff then by all means build it without any suspension travel. It is not needed to see how the diff works.

I am working on making the tatra suspension with the unimog parts. It will be 26 studs wide inclusive unimog wheels. It is 21 studs wide without wheels.

I've been busy today but will try now to start building a proper studless version of the studded prototype i built yesterday. I'm not used to studless and now it's for real so it'll take a while. I'm still not sure this will be a good thing since half the wheels wont be powering it, but i'm not building a TT so the power loss shouldn't be so bad and i really like the thought of proper Tatra suspension so i'm going for it. Maybe in a few days i will have finished the torque tube and have mounted a motor so i can test it and see how it performs.

Here is my design using the unimog ball joints.

I don't have balloon tires, but i think that this one might work good with the tires from 9398.

Nice work. Could you post some closeups as well. Here is a challenge for you, make a steerable axle. BTW the tires lean a little too much i think so if you could also straighten them up a bit it would look better, especially since you don't use balloon tires. Neither does the original.

This is the first suspension i ever made, so it will be a challenge to make it steerable. If i will be able to make it steerable, i will probably build a truck around it to test it. Should I make photo instructions?

The suspension arm needs to be longer. This won't have very much travel.

skppo is right- those shocks will just adjust the camber. There is also too much camber angle in the wheels and it is quite a bit too wide. But a good start and a nice concept.

I'll try to build something today and test it out.

Good luck on your project!

TLH

I agree as well, the swing arm is much to short for such large shock absorbers. Maybe you could try it with 6L shock absorbers. Good Luck!

try and turn the hole thing around?

so the small side of the baljoint is on the chassis side and the long side on the wheel.

then maybe it could work.

grtz

Johnny

Edited February 1, 201411 yr by Johnny P

I agree as well, the swing arm is much to short for such large shock absorbers. Maybe you could try it with 6L shock absorbers. Good Luck!

I don't own the 6L shock absorbers. I will soon try to do Johnny P's idea.

keep us updated on the progress. i have never tried it before and i have a tatra 8*8*8 here. so maybe i could use some of your ideas.

grtz

johnny

I like very much Tatra trucks but I don´t know why, may be for the original idea that they use... anyway I have build 4 of them.

Tatra 813 8x8 http://www.brickshel...ry.cgi?f=499607

Tatra 815 4x4 http://www.brickshelf.com/cgi-bin/gallery.cgi?f=496604

Tatra Kolos 8x8 http://www.brickshel...ry.cgi?f=528328

Tatra 815 10x10 http://www.brickshel...ry.cgi?f=530743

I really really like them .

Edited February 3, 201411 yr by jorgeopesi