Recommended Posts


I'd like to present a bus Solaris Urbino 12 IV.



Scale 1:15

Length 103s / width 23s / height 27s (83/18/22 cm)

Weight: 5,4 kg

Front suspension: Independent, double-wishbone

Rear suspension: Live axle

Suspension with kneeling system


2-speed gearbox

AA+AAA Battery Boxes

7 motors


Driving - 2XLs

Steering - L

Opening doors - M

Kneeling system - L + Servo

Changing gears - M

LED headlights

Working steering wheel


Some time ago I decided to build a bus. I chose Solaris, beacuse it's a polish concern, which is producing buses and trams. I started building in mid-Febraury, and I finished it few days ago.


The biggest challenge was to construct a strong chassis. We need to remember that it's a low-floor bus. The drive motors and the gearbox are (like the real one) located veritically on the left, behind the rear axle. It's causing big stress and I had to overcome it by the chassis. It consist of 3 parts: at the bottom there is a floor 2s thick, built from panels 5x11 and frames; at the top there are beams 3x3s on each side of the bus, they are built from liftarms. These two elements are combined by 7 rungs. The construction of the chassis is similar to the hulls of ships and planes.


The bus is driven by 2 XLs. Gearbox ratio:

I - 12,6:1

II - 4,2:1

The gearbox is built from frames, using 2 gear 24, 1 gear 12 and 1 gear 36. The gears are changed by M motor and mini linear actuator. The biggest problem was to lead the drive from gearbox to the axle. It is the weakest point of the bus - 2 universal joints, connected to the gearbox and to the axle, under a load break.


For steering I used L motor with reduction 14,4:1. It propels the gear rack 1x13 and also the steering wheel.


Front suspension is independent with 2 yellow 6.5L absorbers per wheel.

Rear is live axle. It has 1 grey and 5 yellow 6.5L absorbers (1 grey and 2 yellow for the right side and 3 yellow for the left side).

Opening doors + kneeling system

The doors are opened by M motor, reducted by 40:1. The drive is transmitted by liftarms used as links.

The kneeling system is realised by 2 medium pneumatic cylinders. The pneumatic wires are connected only from one side, so the bus can rise using the absorbers. L motor drives the compressor and servo opens the valve with reduction 3:1. These 3 motors are electrically coupled, so in each door there is a gear with clucth. Thanks to that, the compressor doesn't stop at any time.

The most wanted photos :)


From the top


From the bottom

Some photos

11.jpg_thumb.jpg 13.jpg_thumb.jpg 14.jpg_thumb.jpg 2.jpg_thumb.jpg 15.jpg_thumb.jpg 16.jpg_thumb.jpg

18.jpg_thumb.jpg 19.jpg_thumb.jpg 28.jpg_thumb.jpg 24.jpg_thumb.jpg 23.jpg_thumb.jpg 25.jpg_thumb.jpg


Edited by Porsche96

Share this post

Link to post
Share on other sites

Well ... looks like a big red box on wheels (as most busses do). Would be nice if you highlighted the special features (with photos) regarding for example the suspension, engine, steering ... etc.

Maybe also some 'basic' LDD screenshota to explain how the various mechanisms operate.

Good Job!

Share this post

Link to post
Share on other sites

Heh, just started working as a busdriver last week. And this bus was at work as a (fully electric) demo model,. You captured the look well! And i like how you designed it. But why not use those hub parts on the rear axle? Even though they still allow some play, it should decrease the sagging somewhat,..

Edited by Sylvian

Share this post

Link to post
Share on other sites

Thanks for nice words :) I didn't use hub parts, beacuse they don't affect on the sagging. They also cause that the rear axle is wider.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.