IS 12077:1987 is the Indian Standard (BIS) for testing of timbers for plywood manufacture. This standard outlines the code of practice for testing and evaluating the suitability of different timber species for plywood manufacturing. It covers the entire process from log selection, peeling, veneer drying, and gluing to the final testing of the produced plywood panels to determine their properties and grade.
Code of practice for testing of timbers for plywood manufacture
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Glue Bond Test (Exterior) | Boiling Water Resistance (BWR) Test: 8h boil, 16h drying (60°C), 8h boil, then test wet. | Class 3 Test: 4h boil, 16-20h drying (60°C), 4h boil, then test wet. | EN 314-1:2004 |
| Tensile Shear Test Specimen (Glue Bond) | Overall size 82.5 x 25 mm with a test area of 6.25 cm². | Overall size 100 x 25 mm, with notches creating a 25 x 25 mm shear area. | EN 314-1 / ISO 24294 |
| Qualitative Bond Assessment | Knife Test: A primary method where a knife is used to pry veneers apart and assess failure type. | Chisel Test: A similar concept used mainly for factory production control, not as the primary standard test method. | AS/NZS 2098.2 |
| Log Conditioning Guidance | Prescriptive temperature ranges based on wood density (e.g., 65-80°C for wood >700 kg/m³). | Not specified; procedure must be 'appropriate for the species' and recorded. | ISO 24294:2020 |
| Veneer Thickness Measurement | Measure with a dial gauge to an accuracy of 0.01 mm. | Measure to nearest 0.01 mm with a micrometer having a specified anvil diameter and pressure. | ISO 24294:2020 |
| Final Suitability Classification | Classified into groups: Very suitable, suitable, moderately suitable, not suitable. | No formal classification; provides a detailed report of test results for the user to interpret suitability. | ISO 24294:2020 |