Wooden Tool Handles General Requirements

IS 620: Scope & Key Specifications for Wooden Tool Handles

Scope (Clause 1.3 & 2.1)

• Applies to wooden tool handles made from Indian timbers.
• Defines sampling and testing criteria for quality control.
• Refers to IS 707-1976 for timber definitions.

Sampling & Testing (Table 2)

• For lots ≤ 200, tests agreed between purchaser and supplier.

Tolerances (Clause 6.2)

• At fitting points (head/socket/blade): ±2 mm
• Overall length tolerances:
  • Up to 300 mm: ±3 mm
  • 310 to 600 mm: ±5 mm
  • Above 610 mm: ±10 mm

Timber Suitability (Appendices B & C)

• Lists species with suitability coefficients, e.g.:
  • Acacia tortilis (Israeli babool): 87
  • Eucalyptus tereticornis (Mysore gum): 77
  • Acacia mearnsii (Black wattle): 67

This standard ensures quality and uniformity in wooden tool handles by specifying sampling, tolerances, and suitable timber species.

IS 620 - Definitions & Sampling Specifications

• Definitions: As per Clause 2.1, definitions follow IS 707-1976 and additional terms in IS 620.

• Sampling & Testing (Clause 1.3 & Table 2):
  Number of tool handles to sample and permissible defective handles based on lot size:

• For lots ≤ 200, testing details are mutually agreed.

• Criteria for Conformity (Clause F-2.1):
  The lot conforms if defective handles ≤ permissible number in the above table.

• Tests on samples (Clause F-1.3.2):

  • Dimensional checks
  • Moisture content
  • Performance tests

This ensures quality control of tool handles per IS 620.

IS 620: Classification of Tool Handles

1. Classification by Tool Type & Length (Clause 1.5 & 3.1)

2. Suitability Coefficient (Clause 2.1.1)

• Evaluated based on shock resistance, bending strength, resilience, stiffness, and hardness of timber species.
• Timber choice depends on these mechanical properties to ensure durability and safety.

3. Dimensions (Clause 6.1)

• Handles must conform to dimensions specified in relevant IS standards for each tool type.
• Refer to individual IS codes for detailed dimensional tables.

Summary Diagram: Tool Handle Classification

graph TD
    A[Tool Handles] --> B[Class 3: Light Duty Striking (≤60cm)]
    A --> C[Class 4: Scooping Tools]
    A --> D[Class 5: Cutting & Shaping Tools]

For exact timber species and dimensional details, consult IS 620 full text and related IS standards on specific tools.

IS 620: Timbers Suitable for Various Classes of Tool Handles

Classes of Tool Handles (Clause 1.5)

• Class 3: Handles ≤ 60 cm for light striking tools (e.g., 2 kg adzes, 1.5 kg smith hammers).
• Class 4: Handles for scooping tools (shovels, rakes).
• Class 5: Handles for cutting/shaping tools (chisels, saws, screwdrivers).

Suitability Coefficient (Clause 2.1.1)

• Evaluated based on shock resistance, bending strength, resilience, stiffness, hardness.
• Axlewood (Anogeissus latifolia) = 100 (reference).

Key Timber Tables for Tool Handles

*Tentative values estimated from specific gravity.

Notes:

• Class 4 uses timbers from Class 1 & 2.
• Higher coefficient → better suitability.
• Use Appendices A to E for detailed species lists per class.

flowchart TD
    A[Tool Handle Classes] --> B[Class 3: Light Striking Tools]
    A --> C[Class 4: Scooping Tools]
    A --> D[Class 5: Cutting/Shaping Tools]

    B --> E[Timbers: Maple, Haldu, Silver Oak]
    C --> F[Timbers: Class 1 & 2 species]
    D --> G[Timbers: Chaplash, Birch, Dillenia]

    subgraph Suitability Coefficient
        direction LR
       

IS 620: Manufacture and Seasoning of Tool Handles

Key Specifications:

• Moisture Content:
  • Between 8% and 15% after seasoning (Clause 4.2).
• Defects:
  • No centre heart (pith), rot, checks, shakes, splits (except minor hair splits), borer holes, warp, or defects that reduce life or utility (Clause 4.2).
• Timber Species:
  • Identification as per IS 4970-1973 (Clause 9.1.1). Mixed species must be kept separate.

Manufacture & Treatment:

• Immediately after manufacture:
  • Dip handles momentarily in raw linseed oil at room temperature to stabilize moisture (Clause 5.1.1).
• Post-inspection treatment:
  • Soak accepted handles in hot raw linseed oil (~90°C) for 1 hour, then drain and wipe dry (Clause 10.1).

Summary Table: Seasoning & Treatment

flowchart LR
    A[Manufacture of Handles] --> B[Dip in raw linseed oil (room temp)]
    B --> C[Seasoning to 8%-15% moisture]
    C --> D[Inspection]
    D -->|Accepted| E[Soak in hot linseed oil (90°C, 1 hr)]
    E --> F[Drain & wipe dry]
    F --> G[Ready for dispatch]

This process ensures durability, stability, and resistance to defects in tool handles.

IS 620: Dimensions and Tolerances for Tool Handles

Key Specifications

• Dimensions (Clause 6.1):
  Tool handles must conform to dimensions specified in relevant Indian Standards for each tool type.

• Tolerances (Clause 6.2):

  • At the head, socket, blade, or tongue (where fitting occurs):
    +3 mm tolerance allowed
  • At other places on the handle:
    ±2 mm tolerance allowed

Additional Notes

• Handles should be made from seasoned blanks and shaped as required (Clause 5.1).
• Recommended treatment: Dip in raw linseed oil immediately after manufacture to stabilize moisture content.

Summary Table of Tolerances

Quality Control (Clause 2.1)

• Lot conformity is based on the number of handles failing characteristics not exceeding limits in Table 2 of the standard.

flowchart LR
    A[Tool Handle Dimensions] --> B{Location on Handle}
    B -->|Head/Socket/Blade/Tongue| C[+3 mm Tolerance]
    B -->|Other Places| D[±2 mm Tolerance]
    A --> E[Manufactured from seasoned blanks]
    E --> F[Dip in raw linseed oil]

This ensures proper fit and finish per IS 620 for reliable tool handle performance.

IS 620: Workmanship and Finish - Key Points

1. General Workmanship (Clause 7.2)

• Finish: Should be reasonably good, ensuring usability and durability.

2. Tolerances (Clause 6.2)

• Dimensional tolerances:
  • +3 mm where the head, socket, blade, or tongue fits.
  • ±2 mm at other places.

3. Permissible Defects (Clause 8.1, Table 1)

Note: Unlimited sapwood allowed for handles made from axle wood, yon, kardahi, ash, black chuglam, haldu, and kaim.

4. Sampling & Inspection (Clause 1.3, Table 2)

For lots ≤ 200, tests as mutually agreed.

This ensures quality control for tool handles with defined limits on defects and dimensional accuracy.

IS 620: Permissible Defects in Wooden Tool Handles

Key Specifications (Clause 8.1, Table 1)

Note: Unlimited sapwood allowed for handles made from axle wood, yon, kardahi, ash, black chuglam, haldu, and kaim.

Sampling & Acceptance Criteria (Clause 1.3, Table 2)

For lots ≤ 200, testing criteria are mutually agreed.

Summary

• Grain deviation max 5%.
• Pin knots strictly limited, especially near tool end.
• Sapwood limited except for specific woods.
• Sampling follows strict acceptance with zero tolerance for defects in smaller lots.

flowchart TD
    A[Start: Wooden Handle] --> B{Check Grain Deviation}
    B -- ≤ 1 in 20 --> C{Check Pin Knots}
    B -- > 1 in 20 --> X[Reject]
    C -- Meets criteria --> D{Check Sapwood}
    C -- Exceeds criteria --> X
    D -- Within permissible limits --> E[Accept Handle]
    D -- Exceeds limits --> X

This ensures quality and durability per IS 620.

IS 620: Testing Requirements for Tool Handles

Sampling & Testing (Clause F-1.3.2)

• Samples selected per F-1.3 must be tested for:
  • Dimensional requirements
  • Moisture content
  • Performance tests

Sampling Size & Criteria for Conformity (Table F-1, Clause 1.3 & F-2.1)

• For lots ≤ 200, testing and sample size are mutually agreed between purchaser and supplier.

Summary

• Select samples according to lot size (see table).
• Test all selected samples for dimensional accuracy, moisture content, and performance.
• Reject lot if defective handles exceed permissible limit.

flowchart TD
    A[Lot of Tool Handles] --> B{Lot Size}
    B --> |≤ 200| C[Testing as agreed]
    B --> |201-300| D[Select 6 samples]
    B --> |301-500| E[Select 7 samples]
    B --> |501-800| F[Select 8 samples]
    B --> |> 800| G[Select 10 samples]
    D --> H[Test samples]
    E --> H
    F --> H
    G --> H
    H --> I{Defective Handles ≤ Permissible?}
    I --> |Yes| J[Lot Accepted]
    I --> |No| K[Lot Rejected]

This ensures quality compliance per IS 620.

IS 620: Treatment of Tool Handles – Key Points

• Material: Tool handles must be made from seasoned timber blanks (Clause 5.1).

• Oil Treatment:

  • Immediately after manufacture, dip tool handles momentarily in raw linseed oil at room temperature to retard moisture changes (Clauses 5.1, 5.1.1).
  • After inspection, accepted handles are soaked in hot raw linseed oil (~90°C) for 1 hour, then drained and wiped clean (Clause 10.1).

• Purpose: Linseed oil treatment reduces moisture absorption, enhancing durability and dimensional stability.

• Suitability Coefficient (Clause 2.1.1): Evaluates timber species based on:

  • Shock resistance
  • Bending strength
  • Resilience
  • Stiffness
  • Hardness

Summary Table: Treatment Steps for Tool Handles

flowchart LR
    A[Manufacture from seasoned timber] --> B[Momentary dip in raw linseed oil (room temp)]
    B --> C[Inspection]
    C --> D[Soak in hot linseed oil (~90°C) for 1 hour]
    D --> E[Drain and wipe clean]
    E --> F[Ready for use]

This treatment ensures dimensional stability and prolongs handle life by minimizing moisture-related defects.

IS 620: Sampling and Criteria for Conformity of Tool Handles

Sampling (Clause F-1.3.2)

• Samples are selected as per Clause F-1.3.
• Tests to be conducted on samples:
  • Dimensional requirements
  • Moisture content
  • Performance tests

Criteria for Conformity (Clause F-2.1)

• For lots ≤ 200 handles, sampling and tests are mutually agreed between purchaser and supplier.

Notes:

• Sampling method and conformity criteria detailed in Appendix F (Clause 11.1).
• Visual inspection precedes sample testing.

flowchart TD
    A[Start: Lot of Tool Handles] --> B{Lot Size}
    B -->|≤ 200| C[Sampling & Tests as Agreed]
    B -->|201-300| D[Sample Size = 6, Defects Allowed = 0]
    B -->|301-500| E[Sample Size = 7, Defects Allowed = 0]
    B -->|501-800| F[Sample Size = 8, Defects Allowed = 0]
    B -->|>800| G[Sample Size = 10, Defects Allowed = 1]
    D --> H[Conduct Dimensional, Moisture & Performance Tests]
    E --> H
    F --> H
    G --> H

This ensures quality control by limiting defective handles in sampled batches.

IS 620: Marking - Key Points & Tables

Clause 12.1.1: Marking

• Tool handles may be marked with the ISI Certification Mark.
• ISI Mark assures compliance with the standard via inspection, testing, and quality control.
• Use of ISI Mark is regulated by Indian Standards Institution (Certification Marks) Act.

Sampling & Conformity Criteria (Clause 2.1 & Table 2)

• For lots ≤ 200, sampling/testing is mutually agreed.

Summary:

• ISI Mark signifies verified quality.
• Sampling size and allowable defects depend on lot size.
• Ensures consistent quality and conformity for tool handles.

flowchart TD
    A[Tool Handle Production] --> B{Visual Inspection}
    B -->|Pass| C[Mark with ISI Certification Mark]
    B -->|Fail| D[Reject or Rework]
    C --> E[Sampling as per Table 2]
    E --> F{Defects within permissible limit?}
    F -->|Yes| G[Lot Accepted]
    F -->|No| H[Lot Rejected]

IS 620: Timbers for Class 1 Tool Handles

Key Specifications for Class 1 Handles

• Used for heavy-duty striking tools (e.g., hammers, axes).
• Suitability based on shock resistance, bending strength, resilience, stiffness, hardness.

Timber Selection (Appendix A)

Notes:

• Coefficient reflects relative suitability vs. Axlewood (100).
• Higher values indicate better performance for tool handles.
• *Tentative values estimated from

IS 620: Key Data for Timbers for Class 2 Handles

Class 2 Handles: Timbers suitable for Class 2 handles include all Class 1 timbers plus additional species listed in Appendix B.

Important Specifications from Appendix B (Class 2 Handles)

IS 620: Timbers for Class 3 Handles (Light Duty Striking Tools)

1. Classification (Clause 1.5 c)

• Class 3 handles: Up to 60 cm length for light striking tools like:
  • 2 kg Indian adzes
  • 1.5 kg smith hammers
  • 2 kg splicing wire hammers
  • 1.75 kg tinmans hammers

2. Suitable Timbers (Appendix C, Clause 4.1)

*Suitability Coefficient considers shock resistance, bending strength, resilience, stiffness, and hardness.

3. Notes

• Coefficients are relative to Axlewood (Anogeissus latifolia) = 100.
• Some values are tentative, estimated from specific gravity.
• Handles must be manufactured from these timbers for durability and safety.

Summary Diagram: Timber Selection Process for Class 3 Handles

flowchart TD
    A[Identify Tool Class] --> B{Class 3?}
    B -- Yes --> C[Select Timber from Appendix C]
    C --> D[Check Suitability Coefficient]
    D --> E[Manufacture Handle

IS 620: Timbers for Class 4 Handles (Scooping Tools: Shovels, Rakes, Spades)

Key Specifications:

• Class 4 handles use the same timbers as Class 1 and Class 2 handles (Appendices A & B).
• Class 4 handles are for scooping tools requiring moderate strength and shock resistance.

Suitable Timbers (from Appendices A & B):

*Suitability coefficient considers shock resistance, bending strength, resilience, stiffness, and hardness.

Notes:

• Use timbers with higher coefficients for better durability.
• Class 4 handles require a balance of toughness and flexibility.
• Timbers estimated tentatively (marked *) may be revised.

Summary Table for Class 4 Handles:

flowchart LR
    A[Class 4 Handles] --> B[Use Timbers of Class 1 & 2]
    B --> C[Appendix A Timbers]
    B --> D[Appendix B Timbers]
    C --> E[High Suitability Coefficients (100+)]
    D --> F[Moderate Suitability Coefficients (80-90)]

For detailed timber properties, refer to Appendices A & B of IS 620.