Manufacturing Welded Structural Assemblies for High-Precision CNC Machine Bases

Project Overview

In Q2/2025, IDEA received a project from an American industrial machinery manufacturer requiring the production of eight large welded structural assemblies. These assemblies serve as the guide bases for high-power CNC systems and demanded heavy-duty machining, precision welding, and extremely tight flatness tolerances on critical reference surfaces.

Drawing on extensive experience in industrial OEM projects, IDEA handled the full production process — from material preparation and welding to heat treatment, industrial coating, and dimensional inspection using specialized equipment.

Challenges

• Large size and heavy weight (~150 kg per assembly): Required precise setup and careful distortion control after welding.
• Stringent flatness tolerance on reference surfaces: Less than 0.02 mm required.
• High surface finish quality after painting: Even coating, strong adhesion, and durability for harsh industrial environments.
• Comprehensive post-machining inspection: Required CMM, height gauges, and granite surface plates for accuracy verification.

Solutions & Execution

IDEA established a dedicated process to handle this project effectively:

1. Material Preparation and Pre-Machining

• Standard JIS steel plates were plasma cut and ground on contact surfaces.
• Assembly blueprints were prepared to maintain coaxiality and perpendicularity during the welding setup.

2. Precision Welding Assembly

• CO₂ welding was performed with stress control techniques to produce uniform, high-strength, and visually clean welds.
• Custom jigs were used to minimize post-weld deformation of the welded structural assemblies.

3. Precision Machining of Reference Surfaces

• Parts were machined on a large bed milling machine to achieve flatness and mounting face tolerances within ±0.01 mm.

4. Surface Finishing and Inspection

• Dual-layer industrial green coating was applied per customer specifications (RAL code).
• Mitutoyo instruments and granite tables were used to measure flatness, perpendicularity, and parallelism of key surfaces.

Results

• All 8 welded structural assemblies were completed on schedule within 3 weeks, with dimensional accuracy exceeding expectations.
• Sliding key slot tolerance: ±0.01 mm, overall flatness per assembly: <0.02 mm.
• Surface finish met all visual and color uniformity requirements.
• The U.S. customer praised IDEA’s rigorous quality control process and has placed follow-up orders for the next series of assemblies.