Code of practice for the painting of ferrous metals in buildings, Part 2: Painting

Scope of IS 1477 Part 2 - Key Points

IS 1477 Part 2 (1971) covers painting specifications for ferrous surfaces including:

• Painting schedules for interiors and exteriors.
• Selection of primers, undercoats, and finishing coats based on final finish required.
• Reference to Indian Standards for various paint types and colors.

Key Painting Schedules (Table 1 Summary)

Notes:

• Primer IS 102-1962 requires special drying precautions.
• Brushing (B) and Spraying (S) methods specified.
• Total film thickness for optimum protection: ≥100 microns.
• Paint colors and types conform to various IS codes listed in Appendix D.

flowchart LR
    A[Surface Preparation] --> B[Primer Coat]
    B --> C[Undercoat]
    C --> D[Finishing Coat]
    D --> E[Final Finish]

Summary: IS 1477 Part 2 standardizes painting systems for ferrous surfaces, ensuring durability and finish quality

IS 1477 Part 2 — General Requirements for Painting

Key Specifications (Clause 6.2 & Table 1)

• Painting operations must conform to Clauses 3, 4, 5, and selection of paints per Table 1.
• Paint systems are categorized for Interiors and Exteriors with specific primer, undercoat, and finishing coats.

Painting Schedule Summary (Interiors)

Notes

• Primer IS:102-1962 requires special drying precautions.
• Number of coats and thickness ensure durability and finish quality.
• (B) = Brushing, (S) = Spraying.

Common Paint Standards Referenced (Appendix D)

• IS:102-1962 — Red lead priming paint
• IS:133-1965 — Enamel undercoating and finishing
• IS:207

Key Specifications & Painting Schedule for Paint Film Composition (IS 1477 Part 2)

Paint Film Components (Clause 3.3)

• Paint film = Primer + Filler + Undercoating + Finishing coats.
• Selection depends on exposure: interior, exterior, corrosive atmosphere.
• No all-purpose paint; consult manufacturers for special conditions.

Painting Schedule for Ferrous Surfaces (Clause 5.2 & Table 1)

| Exteriors | | | | | | Full Gloss (Enamel)| 102-1962, 2074-1962 | 2933-1964, 2932-1964 | 2933-1964, 2932-1964 | Same as interiors | | Oil

Primer Coats - IS 1477 Part 2 (1971)

Key Specifications:

• Application Timing: Primer coat must be applied immediately after precleaning/pretreatment to avoid contamination (Clause 4.3).
• Application Method: Preferably by brushing to ensure paint penetrates surface depressions and achieves better adhesion. Spray application is allowed except for lead-containing primers.
• Primer Types:
  • Red lead non-setting (ready mixed)
  • Zinc chrome (ready mixed)
  • Red oxide-zinc chrome

Painting Schedule for Ferrous Surfaces (Clause 5.2 & Table 1):

Notes:

• Brush application is preferred for primers to avoid 'holidays' (missed spots).
• For exterior finishes, similar primer specs apply with adjustments in undercoats and finishing coats.
• Primer drying must be ensured before applying subsequent coats (Note 1).

Summary Diagram of Paint Film Layers

graph LR
A[Steel Surface] --> B[Precleaning]
B --> C[Primer Coat (2 coats)]
C --> D[Undercoat (1 coat)]
D --> E[Finishing Coat (2 coats)]

References:

• IS: 102-1962 (Primer Paint)
• IS: 2074-1962 (Red Lead Primer)
• IS: 133-1965, IS: 2933-1964 (Undercoats and Finishing)
• IS:

IS 1477 Part 2 - Filler and Undercoating Summary

1. Filler Coats (Clause 5.1 & 6.2.2)

• Purpose: Fill deep dents, smooth surface.
• Use only factory-prepared fillers compatible with primers and paints.
• Avoid site-made fillers (whiting + linseed oil) due to incompatibility.

2. Undercoating (Clause 5.2)

• Applied after primer for a smooth, level base.
• Hides primer/filler imperfections.
• Provides full-bodied color with finishing coat.
• Applied by brush (skilled workman) or spray (smoother finish).
• Wet rub after drying for smoothness before finishing.

3. Painting Schedule & Specifications (Table 1, Clause 5.2)

IS 1477 Part 2: Painting Operations & Application Methods

Key Specifications (Clause 6.2 & Table 1)

Application Notes:

• (B) = Brushing; (S) = Spraying
• Primer IS 102-1962 requires special drying precautions.
• Total film thickness ≥ 100 microns for optimum durability.

Troubleshooting Paint Spray (Clause 2.6)

Summary Diagram of Painting Layers

graph LR
A[Surface] --> B[Primer Coats (2)]
B --> C[Undercoat (1)]
C --> D[Finishing Coats (2)]
D --> E[Final Film Thickness ≥ 100 microns]

For detailed paint types

IS 1477 Part 2: Removal of Old Paint and Repainting — Key Points

1. Removal of Old Paint (Clause 7.6 & 7.6.1)

• Use alkali-based or solvent-type paint removers cautiously.
• Alkali removers: Risk damaging adjacent materials (e.g., wood) during washing.
• Solvent removers: Beware of fumes and fire hazards.
• Remove all wax traces after solvent use to ensure proper paint adhesion.

2. Inspection Before Repainting (Clause 8.2.2)

• Inspect to decide:
  • If complete removal of old paint is necessary.
  • If repainting over existing paint is sufficient without removal.

3. General Specifications (Clause 7.5.1)

• Follow known painting specifications for surface preparation and paint application.

Practical Recommendations:

flowchart TD
    A[Inspect Old Paint] --> B{Is paint adhesion good?}
    B -->|Yes| C[Repaint over existing paint]
    B -->|No| D[Remove old paint]
    D --> E[Choose removal method: Alkali or Solvent]
    E --> F[Clean surface (remove wax, dirt)]
    F --> G[Apply new paint as per spec]

Summary: Proper inspection and careful use of paint removers are critical to ensure longevity and adhesion of repainting work per IS 1477 Part 2.

IS 1477 Part 2 (1971) - Inspection and Testing: Key Points

1. General (Clause 8.1)

• Inspection = continuous supervision during all painting stages.
• Tests should be non-destructive or limited destructive (restorable areas only).
• Aim: Ensure recommended practices and final quality.

2. Inspection During Surface Preparation (Clause 8.3)

• Hand-scraping (8.3.2b):
  • No strict inspection method.
  • Ensure removal of all loose rust, scale, and paint.
• Chemical rust removal (Pickling) (8.3.2c):
  • Confirm complete washing to remove acid traces.
  • Inspect inaccessible corners carefully.

3. Inspection Before/During Intermediate Protective Treatments (Clause 8.4)

• Prevent fresh rust/contamination between cleaning and protective coating.
• Verify compliance with:
  • IS 1477 recommendations.
  • Manufacturer’s instructions.

Summary Table: Inspection Focus Areas

Recommended Inspection Practices

• Use visual checks for surface cleanliness.
• Employ non-destructive tests like adhesion tape tests or thickness gauges.
• Document inspection results at each stage.

flowchart TD
    A[Start: Surface Preparation] --> B{Method}
    B -->|Hand-scraping| C[Remove loose rust/paint]
    B -->|Chemical pickling| D[Wash to remove acid]
    C --> E[Inspect surface]
    D --> E
    E --> F[Apply intermediate protective treatment]
    F --> G[Inspect for contamination & adherence]
    G --> H[Final painting]

This ensures quality control through all painting stages per IS 1477 Part 2.

IS 1477 Part 2: Brush Application Techniques (Clause 6.3, Appendix A)

Key Specifications & Guidelines

• Paint Container Usage (A-1.3):

  • Use small paint containers filled to ~75% capacity for brush application.
  • Clean containers only with compatible paint thinners.

• Brush Handling (A-2.1):

  • Hold brush at ~45° angle to vertical surface.
  • Apply several light strokes to transfer paint initially.
  • Rotate brush through 180° to use paint on both bristle faces.
  • Spread paint with gentle pressure for uniform coating.
  • Use ends of bristles, not sides, to contact surface.

• Brush Quality (A-1.1):

  • Use clean brushes free from dried paint.
  • Ensure no objectionable pulling or lapping streaks.
  • Brush must produce uniform, streak-free finish.

Summary Table

flowchart LR
    A(Paint in container ~75%) --> B(Hold brush at 45°)
    B --> C(Apply several light strokes)
    C --> D(Rotate brush 180°)
    D --> E(Spread paint with gentle pressure)
    E --> F(Ends of bristles contact surface)
    F --> G(Uniform coating, no streaks)

This ensures efficient paint transfer and a smooth, uniform finish as per IS 1477 Part 2.

IS 1477 (Part 2) - 1971: Spraying of Paint - Key Points

Spraying Technique (Clause 2.1)

• Hold spray gun perpendicular to surface.
• Use uniform sweeping motion.
• Adjust air pressure and fan for best coverage with minimum wastage.
• Avoid too high air pressure to prevent paint fogging.

Spray Gun Stroke Method (Fig. 2)

1. Begin stroke, then pull trigger.
2. Move gun in a straight line parallel to surface.
3. Release trigger before completing stroke.
4. Maintain gun perpendicular to surface.

Paint Thinning (Clause B-1.1)

• Paints are usually ready for spraying.
• Thin only if necessary, and minimally.
• Nitrocellulose lacquers require special thinner.

Troubleshooting Paint Leaks (Clause 2.6, Table C-2.6)

Indian Standards on Paints (Appendix D)

• Ready mixed paints for brushing and spraying are specified under various IS codes (e.g., IS 114-1950, IS 117-1964).
• Standard colours are listed under these IS codes for interior and exterior applications.

Summary Diagram of Spray Gun Stroke

flowchart LR
    A[Begin Stroke] --> B[Pull Trigger]
    B --> C[Move Gun Parallel to Surface]
    C --> D[Release Trigger before End]
    D --> E[Maintain Gun Perpendicular]

For detailed paint specifications and colours, refer to IS codes listed in Appendix D of IS 1477 (Part 2).

IS 1477 Part 2: Spray Painting Defects – Causes & Remedies

Key Defects & Remedies (Appendix C)

Spray Gun Stroke Technique (Fig. 2)

• Start stroke, then pull trigger
• Move gun in straight line, parallel to surface
• Release trigger before stroke ends
• Hold gun perpendicular to surface

flowchart LR
    A[Start Stroke] --> B[Pull Trigger]
    B --> C[Move Gun Straight & Parallel]
    C --> D[Release Trigger Before End]
    D --> E[Hold Gun Perpendicular]

Maintain equipment cleanliness and proper technique for best finish quality.

IS 1477 Part 2 - Referenced Indian Standards on Paints and Enamels

This part of IS 1477 (1971) lists key Indian Standards related to paints and enamels, specifying ready mixed paints for various applications and colors.

Key Specifications & Indian Standards:

Notes:

• Colors are standardized by IS numbers (e.g., No. 101 Sky Blue).
• These standards cover paints for interior/exterior, brushing/spraying