Methods of test for clear finishes for wooden furniture, Part 2: Resistance to wet heat

IS 5807 Part 2 — Scope & Key Specifications

Scope Summary (Clause 4.1.2)

• Defines agreement terms between purchaser & seller for testing clear finishes on wooden furniture.
• Covers assessment of surface changes after exposure (e.g., heat, ageing).

Key Tables & Ratings

Table 1: Rating of Test Results (Clause 6.2)

Table 7: Acceptability Criteria (Clause 7.1)

Notes:

• Ageing periods other than 28 days must be reported with reasons (Clause 7.2).
• Ratings are based on average of five readings.

flowchart TD
    A[Start: Test Clear Finish] --> B{Assess Surface Changes}
    B --> C[Visible Marks]
    B --> D[Colour Change]
    B --> E[Loss of Gloss]
    B --> F[Surface Imperfection]
    C --> G{Rating ≥ 3?}
    D --> H{Rating ≥ 3?}
    E --> I{Rating ≥ 2?}
    F --> J{Rating = 5?}
    G --> K[Accept/Reject]
    H --> K
    I --> K
    J --> K

Summary: IS 5807 Part 2 standardizes evaluation of clear finishes on wood by rating visible defects, color change, gloss loss, and surface imperfections with defined acceptance thresholds.

IS 5807 Part 2 (1975) - References Summary

The code references various Indian Standards related to painting, finishing, and allied finishes for building materials. Key referenced IS codes include:

Additional Notes:

• Clause 7.2 requires reporting any ageing periods other than 28 days with reasons.
• The code is supported by extensive IS publications covering civil engineering materials, construction practices, and finishes.
• ISI offices and bulletins provide updates and subscription details for standards.

This network of standards ensures comprehensive guidelines for surface finishes and testing for various materials in construction.

graph LR
A[IS 5807 Part 2] --> B[Painting of Metals (IS 1477)]
A --> C[Wood Finishing (IS 2338)]
A --> D[Concrete Painting (IS 2395)]
A --> E[Non-Ferrous Metals (IS 2524)]
A --> F[Wood Finishes Testing (IS 5807 Part I)]

IS 5807 Part 2: Apparatus for Heat Resistance Test

Key Apparatus & Specifications (Clause 3.1)

• Brass Cup

  • Material: 70/30 arsenical brass, electroplated per IS:4827-1968 (Service Grade No. 2)
  • Weight: 440 ± 25 g
  • Dimensions: As per Fig. 1 (typically standardized; see IS 5807 Part 2 Fig. 1)

• Nylon Cloth

  • Plain weave white nylon
  • Size: ~75 mm square
  • Used wet (thoroughly wetted, not dripping)

• Insulating Mat

  • Minimum size: 100 mm square
  • Material example: 10 cm thick wooden panel

• Mineral Oil

  • Open flashpoint ≥ 250°C
  • Quantity: 100 ± 1 g per test

• Viewing Cabinet (Fig. 2)

  • Material: 16 mm thick blockboard or similar
  • Interior: Painted matt black
  • Features: 25 mm diameter hole on sloping side; 60 W frosted bulb positioned over hole for illumination

Test Preparation Summary (Clause 5.2)

1. Heat mineral oil in brass cup above test temperature.
2. Place cup on insulating mat; stir oil while cooling to test temperature.
3. Wet nylon cloth in distilled water, squeeze excess water.
4. Spread cloth on test panel; test areas ≥ 65 mm apart and ≥ 40 mm from edges.

Visual Summary (Conceptual)

graph LR
A[Brass Cup] --> B[Filled with 100g Mineral Oil]
B --> C[Heated above test temp]
C --> D[Placed on Insulating Mat]
D --> E[Oil cooled to test temp]
E --> F[Nylon Cloth soaked & placed on test panel]
G[Viewing Cabinet] --> H[Observation through 25mm hole]

This apparatus setup ensures reproducible heat resistance testing of wood finishes per IS 5807 Part 2.

IS 5807 Part 2: Preparation of Test Surface - Key Specs & Formulas

1. Test Panel Dimensions (Clause 4.1)

• Minimum panel size: 250 mm × 150 mm
• Test area diameter: 50 mm
• Spacing between test centers: ≥ 65 mm
• Distance from edge: ≥ 40 mm

2. Aging Conditions for Final Coat (Clause 4.1.2)

• Temperature: 27 ± 2°C
• Relative Humidity: 65 ± 5%
• Aging Period: ≥ 28 days (can be reduced by agreement)

3. Apparatus for Test Surface Preparation (Clause 3.1)

Summary Diagram: Test Surface Setup

flowchart LR
    A[Test Panel] --> B[Test Area (50 mm dia)]
    B -- Centers ≥ 65 mm apart --> C[Multiple Test Areas]
    A -- Edges ≥ 40 mm --> D[Safe Margin]
    E[Final Coat] --> F[Aging: 27±2°C, RH 65±5%, ≥28 days]

This standardizes test surface prep ensuring reproducible and comparable results for wood finish durability against marking.

IS 5807 Part 2: Test Procedure Key Points

Apparatus (Clause 3.1)

• Brass Cup: 70/30 arsenical brass, electroplated, weight = 440 ± 25 g (Fig. 1 dimensions).
• Nylon Cloth: Plain weave, white, ~75 mm square, soaked in distilled water.
• Insulating Mat: ≥ 100 mm square, e.g., 10 cm thick wooden panel.
• Mineral Oil: Flashpoint ≥ 250℃, used to fill cup (100 ± 1 g).
• Viewing Cabinet: 16 mm blockboard, matt black interior, 25 mm hole with 60W frosted bulb (Fig. 2).

Preparation of Test Surface (Clauses 4.1.2 & 5.2)

• Final coat aged 28 days at 27 ± 2°C, 65 ± 5% RH.
• Fill brass cup with mineral oil, heat above test temp (55–100℃).
• Cool oil on insulating mat, stir to uniform temperature.
• Nylon cloth wetted (not dripping) placed over test panel.
• Test areas: 50 mm diameter, centers ≥ 65 mm apart, ≥ 40 mm from edges.

Test Conditions (Clause 5.1)

• Test temperature: 55 to 100℃ (agreed between parties).
• Ambient: 27 ± 2℃, draught-free atmosphere.

Summary Table: Test Setup

flowchart TD
    A[Prepare brass cup with mineral oil] --> B[Heat oil above

IS 5807 Part 2: Assessment and Reporting of Results

Key Specifications:

1. Rating of Test Areas (Clause 6.2, Table 1)

2. Examination Procedure (Clause 5.3)

• Position test panel 550 mm from cabinet back.
• Test area equidistant from sides.
• Move eye to reflect lamp bulb around test area to detect markings.

3. Rating Operation (Clause 6.3)

• Minimum 5 independent assessors.
• No intermediate ratings (e.g., 2.5) allowed.

4. Acceptability Criteria (Clause 7.1, Table 7)

Summary Diagram of Rating Process

flowchart TD
    A[Position Panel] --> B[Examine Test Area]
    B --> C[Assessors Rate (5 persons)]
    C --> D[Calculate Average Rating]
    D --> E{Rating >= Minimum?}
    E -- Yes --> F[Accept Test Area]
    E -- No --> G[Reject Test Area]

This process ensures consistent, objective evaluation of test panels per IS 5807 Part 2.

IS 5807 Part 2: Acceptability Criteria Summary

1. Rating Scale (Clause 6.2, Table 1)

2. Minimum Qualifying Average Ratings for Acceptance (Clause 7.1, Table 7)

3. Assessment Procedure (Clause 6.3)

• At least 5 independent observers rate each test area.
• No intermediate ratings (e.g., 2.5) allowed.
• Final rating = Average of 5 ratings.
• Acceptance if average ≥ minimum rating in Table 7.

Summary Diagram

flowchart TD
  A[Start: Test Area] --> B[5 Independent Observers Rate]
  B --> C[Assign Ratings (1 to 5) per Table 1]
  C --> D[Calculate Average Rating]
  D --> E{Average ≥ Min. Rating?}
  E -- Yes --> F[Accept Test Area]
  E -- No --> G[Reject Test Area]

Note: Purchaser and seller must agree on acceptance criteria (Clause 4.1.2).

IS 5807 Part 2: Repeatability & Special Cases

1. Repeatability (Clause 5.2.2)

• The test procedure shall be repeated three times to ensure consistency and reliability of results.

2. Acceptability Criteria (Clause 7.1, Table 7)

• Average rating is based on five persons' readings.

3. Rating Scale (Clause 6.2, Table 1)

Summary:

• Repeat tests 3 times for repeatability.
• Use average ratings from 5 observers.
• Ratings guide acceptance based on defect type.
• Agreement on special cases should be made between purchaser and seller (Clause 4.1.2).

flowchart TD
    A[Test Procedure] --> B[Repeat 3 Times]
    B --> C[Rate Defects (5 Observers)]
    C --> D{Defect Type}
    D -->|Visible Marks| E[Min R=3]
    D -->|Colour Change| F[Min R=3]
    D -->|Loss of Gloss| G[Min R=2]
    D -->|Surface Imperfection| H[Min R=5]
    E & F & G & H --> I[Accept/Reject]

This ensures consistent, objective evaluation of surface defects per IS 5807 Part 2.

IS 5807 Part 2 - Notes on Substrate and Finish Application

Key Specifications:

• Substrate: Wooden panels must be suitably prepared and comply with agreed dimensions.
• Finish Application: Follow methods in IS 2338 (Part I)-1967 for finishing wood and wood-based materials.
• Aging of Finish: Final coat should age at 27 ± 2°C and 65 ± 5% RH for ≥ 28 days unless otherwise agreed.
• Test Substrate: No uniform standard substrate due to wood diversity; substrate and preparation must be agreed between purchaser and vendor.
• Stained Woods: Test procedure applies also to stained substrates.

Reference Standards:

• IS 2338 (Part I) - Wood finishing workmanship and operation.
• IS 5807 (Parts I, III, IV, V) - Other test methods for finishes (dry heat, oils/fats marking, liquids, glare).
• BS 3962 (Part 2)-1971 - International coordination for wet heat resistance testing.

Summary Table:

flowchart LR
    A[Wooden Substrate] --> B[Surface Preparation]
    B --> C[Finish Application (IS 2338 Part I)]
    C --> D[Aging: 27±2°C, 65±5% RH, ≥28 days]
    D --> E[Testing per IS 5807 Part II]

This ensures consistent finish quality and reliable test results.

IS 5807 Part 2 (1975) Comparison with Other Standards: Key Points

• Clause 4.1.2 & 5.1: Emphasizes purchaser-seller agreement on test conditions, especially ageing periods different from 28 days.

• Clause 7.2 (Acceptability):

  • If ageing period ≠ 28 days, report duration and reason.
  • Ensures transparency and comparability with other standards.

• Referenced Indian Standards for Painting & Finishes:

  • IS 1477 (Parts I & II) – Painting ferrous metals
  • IS 2395 (Parts I & II) – Painting concrete, masonry
  • IS 2524 (Parts I & II) – Painting non-ferrous metals
  • IS 2338 (Parts I & II) – Finishing wood and wood-based materials
  • IS 5807 Part 1 – Resistance to dry heat for clear finishes

• Comparison Approach:

  • Align test methods and acceptance criteria with relevant IS codes.
  • Adapt procedures (e.g., heating liquid changed from water to oil) for better performance relevance.

Summary Table: IS 5807 Part 2 vs Other IS Standards

Practical Note:

Always ensure mutual agreement on test parameters between purchaser and seller for valid comparison with other standards.

flowchart LR
    A[Start: Test Planning] --> B{Ageing Period}
    B -- 28 days --> C[Standard Test]
    B -- Other --> D[Report Duration & Reason]
    C --> E[Use Oil as Heating Medium]
    D --> E
    E --> F[Compare with Other IS Standards]
    F --> G[Acceptance Criteria]
    G