- Double Wishbone Suspension: A complex independent suspension system that allows wheels to move vertically without affecting the vehicle chassis.
- Core Components: Requires Bearings, Bend Pipes, and Suspension Blocks (Sport or Off-road).
- Stability Benefit: Keeps the vehicle level on uneven terrain and prevents tipping during high-speed turns.
- Key Tool: The Weld Tool is essential for connecting the upper and lower control arms to the wheel hub.
- Versatility: Works for both steering and non-steering axles by adjusting the hub bearing configuration.
Understanding Scrap Mechanic Double Wishbone Suspension
The scrap mechanic double wishbone suspension is a staple for advanced builders looking to transition from basic "block-on-spring" designs to high-fidelity, realistic vehicle dynamics. Unlike standard vertical suspension, which often suffers from "glitch-welding" or instability at high speeds, the double wishbone setup uses a series of bearings and pipes to create a parallelogram geometry. This ensures that the wheel remains perpendicular to the ground throughout its travel, providing maximum traction.
In this guide, we will break down the mechanics of the A-arm (wishbone) structure and how to implement it on any chassis size. Whether you are building a heavy-duty crawler or a fast-moving scout car, mastering this suspension type is a prerequisite for professional-tier engineering in Scrap Mechanic.
Video Highlights:
- Material Prep: Essential list of pipes and bearings needed before starting.
- Geometry Setup: How to align the 3x2 rectangle base for optimal clearance.
- Bearing Logic: Placing bearings for both vertical travel and steering.
- Welding Phase: The final step to make the suspension functional.
- Test Drive: Performance demonstration on rocky terrain.
The primary advantage is Independent Wheel Travel. When one wheel hits a rock, the other three remain firmly planted, maintaining control and power delivery.
Required Materials and Parts List
Before starting your build, ensure your inventory is stocked with the following components. The exact number of straight pipes may vary depending on the width of your vehicle, but the bearing count remains relatively consistent for a standard 4-wheel setup.
| Part Name | Quantity (Per Pair) | Primary Function |
|---|---|---|
| Bearings | 16 - 18 | Provides pivot points for the arms and steering |
| Bend Pipes | 26 | Creates the "A" shape of the wishbones |
| 4-Way T-Pipes | 2 | Connects the hub to the upper and lower arms |
| Sport Suspension | 2 | Provides the dampening force; Sport is preferred for stability |
| Straight Pipes | 18+ | Connects the chassis to the suspension assembly |
| Weld Tool | 1 | Vital for closing the mechanical loop of the arms |
While Off-road suspension offers more travel, it is one block longer than the Sport variant. If using Off-road blocks, you must adjust your chassis height by one block to prevent the suspension from dragging.
Step-by-Step Assembly Guide
Building a scrap mechanic double wishbone suspension requires precision. If the bearings are misaligned by even one block, the arms will collide or the weld tool will fail to connect the hub.
Chassis Foundation
Start by extending a 3-block down and 2-block wide rectangle from your main vehicle frame. This acts as the mounting point for your suspension blocks. Place one Sport Suspension block on each side of this rectangle, pointing downward.
Lower Control Arm Construction
Place a bearing at the bottom of the suspension block. Use bend pipes to curve outward, then extend straight pipes (usually 3 blocks long) to define the width of your axle. Repeat this on both sides to create the lower foundation.
Building the Wheel Hub
At the end of your lower arm, place a bend pipe facing downward, then attach a 4-way T-pipe. This T-pipe serves as the "hub" where the wheel and the upper control arm will eventually meet.
Upper Control Arm and Closing the Loop
Mirror the lower arm's structure starting from a bearing placed higher on the chassis. Bring the arm out to meet the top of the 4-way T-pipe. Use the Weld Tool to connect the final pipe segment to the T-pipe, turning the assembly into a solid, functional parallelogram.
Steering Integration
If this is a front axle, place a bearing on the outward-facing port of the 4-way T-pipe before attaching the wheel. Connect this bearing to your Driver's Seat to enable steering. For rear axles, simply attach the wheel directly to a fixed pipe or a non-powered bearing.
After welding, lift the vehicle with your jack and drop it. If the suspension "pops" or the pipes fly off, check for overlapping blocks or bearings that are rotating into the chassis.
Performance Comparison and Use Cases
Choosing the right suspension depends on your vehicle's purpose. The double wishbone is superior for most scenarios, but it occupies more space than a standard swing-arm setup.
| Feature | Standard Suspension | Double Wishbone |
|---|---|---|
| Complexity | Low (1-2 bearings) | High (8-9 bearings per wheel) |
| Stability | Moderate | Excellent |
| Ground Clearance | High | Moderate (due to lower arms) |
| Part Count | Low | High |
| Tipping Risk | High at speed | Low |
Off-Road Exploration
- Maximum Articulation: Allows wheels to climb over large obstacles.
- Level Chassis: Prevents the driver's seat from tilting excessively.
- Durability: Handles hard landings from cliffs without breaking.
High-Speed Racing
- Camber Control: Keeps tires flat on the asphalt during turns.
- Weight Distribution: Manages the shift of weight during braking.
- Precision: Reduces "wobble" common in simpler suspension designs.
Double wishbone systems are heavier. If your vehicle is too light, the suspension might be too "stiff." Adjust the suspension block stiffness settings (1-10) to match your vehicle's total mass.
Tuning and Final Optimization
Once the mechanical build is finished, you must tune the system to ensure it handles correctly under load. A poorly tuned scrap mechanic double wishbone suspension can lead to "bouncing" or unintended steering behavior.
Post-Build Checklist:
- Verify all 4-way T-pipes are welded to both upper and lower arms
- Set suspension stiffness to level 5 as a baseline
- Check that steering bearings rotate in the correct direction
- Ensure wheels have at least 1 block of clearance from the chassis
- Test the vehicle's center of mass using the lift
Handling Width Adjustments
If your vehicle is wider than the standard tutorial build, you have two options:
- Extend Pipe Length: Simply add more straight pipes to the arms. Note that longer arms increase leverage, which may require stiffer suspension settings.
- Spacer Blocks: Place blocks between the chassis and the start of the suspension arms to push the entire assembly outward.
For heavy vehicles, you can double up the suspension blocks. Place two Sport Suspension blocks side-by-side and connect them to the same control arm for double the support strength.
Frequently Asked Questions
Q: Why does my suspension shake or glitch out?
This usually happens due to 'bearing tension.' Ensure that your upper and lower arms are perfectly parallel. If they are angled toward each other, the physics engine will struggle to calculate the movement, causing the shaking.
Q: Can I use this for a 6-wheel or 8-wheel vehicle?
Yes. The double wishbone design is modular. You can repeat the assembly for as many axles as needed. Just ensure your engine has enough power to move the additional weight of the bearings and pipes.
Q: Does the double wishbone suspension work in Survival Mode?
Absolutely. However, it is resource-intensive. You will need a significant amount of metal and components for the bearings. It is recommended to use this for your primary exploration vehicle rather than a basic resource collector.
Q: How do I fix the 'squatting' effect when the vehicle is heavy?
If the vehicle sits too low, increase the stiffness of the suspension blocks. If it still squats at max stiffness, you may need to reduce the length of the control arms to decrease the leverage acting on the springs.