Coating/Marking Rework

Circuit Technology Center provides comprehensive services for the precise removal and application of coatings, solder masks, and legends on circuit board surfaces. Whether driven by design revisions, manufacturing defects, or customer requirements, our experienced technicians modify board surfaces with accuracy and control. Using IPC-recommended methods, we safely remove or reapply coatings without compromising circuitry, even in high-density areas. From selective solder mask repair to legend and marking updates, our processes ensure boards meet original specifications or new requirements, supporting high-reliability applications across aerospace, defense, and advanced electronics industries.

Key Highlights

• Expertise in coating, solder mask, and legend modifications
• IPC-recommended processes ensuring safety and reliability
• Multiple removal methods tailored to coating type and location
• Selective application techniques matching thickness and durability
• Ability to repair or reapply solder masks for BGA sites and other critical areas
• Precision legend and marking modification for compliance and version control
• Trusted by leading industries for complex surface preparation and repairs

Technical Specifications

• Coating and solder mask removal methods:
  * Controlled chemical stripping
  * Micro-abrasion and micro-blasting
  * Thermal and peeling techniques
  * Precision scraping and grinding
• Selective solder mask application and repair with industry-approved materials
• Spot applications and full-area coating options
• Legend and marking removal, modification, and reapplication
• Updated text, symbols, or identification codes for regulatory compliance
• Processes designed for high-density and sensitive circuitry
• Compliance with IPC standards for rework, repair, and modification

• 2.3.1 Coating Removal, Identification of Coating
• 2.3.2 Coating Removal, Solvent Method
• 2.3.3 Coating Removal, Peeling Method
• 2.3.4 Coating Removal, Thermal Method
• 2.3.5 Coating Removal, Grinding/Scraping Method
• 2.3.6 Coating Removal, Micro Blasting Method
• 2.4.1 Coating Replacement, Solder Mask
• IPC-7711/7721 Rework, Modification, and Repair of Electronic Assemblies
• IPC-A-610 Acceptability of Electronic Assemblies
• IPC-JEDEC-J-STD-020 Moisture/Reflow Sensitivity Classification for Nonhermetic Surface Mount Devices
• IPC-JEDEC-J-STD-033 Handling, Packing, Shipping, and Use of Moisture, Reflow, and Process Sensitive Devices
• JESD625C.01_Requirements for Handling Electrostatic-Discharge-Sensitive (ESDS) Devices
• MIL-PRF-38535M Performance Specification Circuits (Microcircuits) Manufacturing, General Specification
• MIL-STD-130- Department of Defense Standard Practice Identification Marking of U.S Military Property
• MIL-STD-202 Test Method Standard Electronic and Electrical Component Parts
• MIL-STD-883-Department of Defense Test Method Standard Microcircuits

Images

Figure 1. Using IPC-recommended methods, we safely remove or reapply coatings without compromising circuitry, even in high-density areas.

Related

2.3.1 Coating Removal, Identification of Coating

Identify conformal coatings before removal to prevent substrate damage. Learn how to distinguish acrylic, urethane, silicone, epoxy and parylene coatings using visual inspection, solvent testing and practical field methods.

2.3.5 Coating Removal, Grinding/Scraping Method

Mechanically remove conformal coatings using precision grinding or scraping techniques. Includes tool selection, depth control and surface protection methods to avoid damage to traces and laminate.

2.3.6 Coating Removal, Micro Blasting Method

Micro blasting removes conformal coatings in precise areas using controlled abrasive media. Learn equipment setup, masking techniques and surface protection methods for accurate coating removal.

2.4.1 Coating Replacement, Solder Mask

Restore solder mask to protect circuitry and maintain electrical isolation. Covers surface preparation, mask application, curing and inspection practices for durable, professional repair results.

2.4.2 Coating Replacement, Conformal Coating, Encapsulant

Reapply conformal coating or encapsulant to protect repaired assemblies from moisture, contamination and electrical stress. Learn material selection, masking and controlled application methods.

2.4.3 Coating Replacement, Solder Mask, BGA Locations

Restore solder mask in BGA locations while maintaining pad geometry and spacing. Detailed procedures ensure insulation integrity and reliable component reinstallation in high-density areas.

4 Techniques for Removing Solder Mask

Unwanted solder mask can be safely removed using controlled methods such as scraping, milling, chemical stripping, or microblasting. Selecting the proper technique protects the PCB surface while restoring access to pads, test points, and critical features.

Solder Mask Rework at a BGA Site

Omitted solder mask at a BGA site causes solder bleed and open/short defects, so technicians manually reapply mask or high-temp epoxy to isolate pads and preserve joint integrity. This hands-on fix prevents solder flow into adjacent circuitry.