Chassis and Suspension Structure Guide

Alpha Model Tech Share Series · 2026 · 1/24, 1/43 Scale
A well-fitted chassis and clean suspension are the foundation of any great build. Here is the full process from parts prep to suspension, drivetrain, wheels and underbody details.

01 · Chassis Parts Preparation

Cleaning Steps

1. Soak the parts in warm detergent water (40–50°C) for 15–20 minutes.
2. Gently brush grooves and holes with a soft-bristled brush.
3. Rinse with clean water and air dry.

Note: do not use hot water — it may cause resin deformation.

Removing Flash

• Use side cutters to remove large gate material.
• Gently shave off remaining residue with a hobby knife held flush against the part surface.
• File flat and finish with 2000-grit sandpaper.

Filling Sink Marks

1. Sand around the air bubble with 800-grit sandpaper.
2. Press Tamiya putty into the void.
3. After fully drying, flatten with 800-grit, then refine with 2000-grit.

02 · Chassis Assembly

Trial Fit (Required Step)

1. Place the parts without applying glue.
2. Confirm left-right symmetry and front-back alignment.
3. Check that the clearance is sufficient.
4. Adjust promptly if issues are found.

Bonding Sequence

1. Bond the chassis main body first (if multi-part).
2. Install the engine mount and align the front edge.
3. Centre and bond the drivetrain channel strips.

03 · Suspension Fabrication

Control Arm Installation

• Bond the upper and lower control arms into the chassis mounting holes.
• Ball joint shapes face outward.
• Angles must be symmetrical on both sides.
• Tip: use Blu-Tack for temporary hold and confirm angles before gluing.

Shock Springs

• Mask connecting areas before painting.
• Spring colors: red / yellow / gold.
• Slightly compress during installation, glue once the fit is confirmed.

Anti-Roll Bar

• Use photo-etch or 0.5mm copper wire.
• Connect to the left-right control arm mounting holes at both ends.
• Confirm free movement before gluing.

04 · Drivetrain System

Engine Assembly

1. Bond engine and transmission together first.
2. Install the entire assembly to the chassis mount.
3. Align front-rear position and ensure the driveshaft can connect.

Differential

• Align with the chassis slots or mounting holes.
• The crown gear faces the correct direction.
• Secure all sides with glue after fully curing.

Driveshaft Fabrication

1. Cut a 0.8–1.0mm brass rod to match the available length.
2. Flatten or grind both ends into universal joint shapes.
3. Give the driveshaft a slight arc.

Driveshaft Installation

1. Insert one end into the differential output flange first.
2. Adjust the angle to align with the front wheel hub position.
3. Trial fit to confirm length, then glue once the fit is confirmed.

05 · Wheel Assembly

Brake Discs

• Install brake discs to the wheel hub carrier first.
• For two-piece units, bond the bell first, then fit the brake disc over it.
• Confirm the bolt holes are aligned.

Brake Calipers

Painting: mask the mounting surfaces, then spray the brand color.

Installation: align with the wheel hub mount, press in, and lightly glue to secure.

Wheel Hubs

1. Install the brake disc and caliper first.
2. Centre the wheel hub with the carrier.
3. The logo on the centre cap faces the correct direction.

Tires

• Stretch the rubber ring onto the wheel hub.
• Important: before installing, check the tire tread direction against the instructions to ensure correct pattern orientation.
• If too loose, apply a small amount of rubber glue to secure.
• Do not glue the entire circumference — leave some flexibility.

06 · Chassis Underbody Details

Exhaust Pipe Fabrication

1. Bend a 0.8–1.0mm brass rod.
2. Draw the routing path on paper first, then gradually bend.
3. Spray Gunze Super Silver HSM01.
4. Scrape the inside of the pipe tip to create a heat-blue color.

Brake Lines

• Use 0.3mm plastic tubing or copper wire.
• Extend from the main reservoir to the front and rear wheels.
• Add slight arcs to convey softness.

Diffuser

• Aerodynamic component under the rear chassis.
• Bond multiple photo-etch sheets in sequence.
• The fin angles flare outward.
• Handle carefully with tweezers.

07 · Painting Process

08 · Common Problems and Solutions

09 · Tool List

• Side cutters, hobby knife (#11), files, sanding sticks (2000 grit).
• 502-style instant glue, Blu-Tack, PVA white glue.
• Gunze primer B-001, paints, clear coat B-502/B-503.
• Needle-nose pliers, flat-nose pliers, tweezers.
• Brass rod (0.8–1.0mm), plastic tubing (0.3mm).

10 · Aftermarket Brands

Hobby Design / Studio27 / Metal York / Reed Holly / Master Model

Build. Detail. Inspire. — Alpha Model Technical Team