3.3.2 End grain balsa
3.3.2.1 End grain balsa wood as a structural core material of the hull shall fulfill the following requirements.
It shall:
- have been treated against fungal and insects attack directly after felling the tree;
- have been kiln-dried within 10 days after felling the tree;
- have been sterilised;
- have an average moisture content of 12% to 15%, when packaged.
3.3.2.2 The mechanical properties when used in the hull structure shall comply with Annex A, Table 2.
3.3.3 Other core materials
Core materials other than listed above may be used if they fulfil the requirements of clause 3.2 and have been proven to be suitable for the intended application in the small craft.
3.4.2.2 When laying up the core material this shall not be bent or deformed to such an extent, that the properties of the core are adversely affected.
3.4.2.3 Irregularities on the core surface and the joints shall be removed.
3.4.2.4 The core surface shall be primed and the voids filled before the laminate is applied.
