Video Presentation

Specifications

• Western Star 6900 Twinsteer in Lego Technic : Scale ≃ 1/20 to 1/25
• Remote controlled using Control+ Hub and PoweredUp App (LEGO) (also compatible with Power Functions systems, see below)
• Drive : 2 L motor with 12/24, 12/20, 20/28 (differential), 8×4, no locking differential
• Steering : L motor which drives both axle with different turning radius made using variable connecting rod
• Winch : L motor with worm gearing
• Suspensions : Tandem bogies with oscillating arms
• Removal hood with fake working inline 6 diesel engine
• Openable doors
• Diesel Mud Pump in container style with optional motorization
• Available in Control+ (PoweredUpp App), Power Functions System (IR Remote), PFS (buwizz) or PFS (2.4hg Battery like Cada)

If you are interested by how I build this model, you can read the full review of this model on the blogpost, or alternatively watch the Design Secrets Videos I did (3 videos).

How to build ?

If you have already the parts : you can purchase the PDF instructions only on this page which also includes the Mud Pump instructions in 4 different versions :

• Control+ (PoweredUpp Smartphone App) + Tutorial for set up the Control Profile in the App (example)
• Power Functions System (IR LEGO Remote)
• Power Functions System (Buwizz battery)
• Power Functions System (2.4hgz battery like Cada one)

If you do not have the parts, you can purchase the complete kit from two different retailers :

• Using Genuine LEGO Parts : This model is available on Buildamoc (Control+ Version) in a complete package including genuine LEGO parts plus the PDF instructions.
• Using non-Genuine LEGO Parts : This model is available on LesDiy Store (PFS+2.4ghz battery version) in a complete package, including the parts (alternative bricks from China) and the PDF Instructions.

Each instruction contains the partlist at the end, but you can check individually on Rebrickable or in the bill of material below :

• Truck only (1511 parts) (Control+)
• Truck only (1524 parts) (PFS + IR Remote)
• Truck only (1519 parts) (PFS + Buwizz or 2.4ghz Battery)
• Mud Pump Only (584 parts)

If you are interested by the Mud Pump only, please see the product page here.

For the Control+ app version : please ensure you first that your device (smartphone, tablet) is compatible with the PoweredUp App From LEGO (available for Android and iOS). (example of the tutorial)

About this product

Instructions preview

Bill Of material

Version on the top right