Document ID: chunk:federal_register_of_legislation:F2005L03990:reg:60:p3
Version: federal_register_of_legislation:F2005L03990
Segment Type: reg
Provision Reference: reg 60 (pt 3/9)
Character Range: 74874–77542

sample to pass this certification, the following conditions shall be met:
 0.308 MPa  S(n)  0.342 MPa for 0.342 MPa material
 1.540 MPa  S(n)  1.711 MPa for 1.711 MPa material
 n = 1, 2, 3.
2.8.  Block crush strength specification
 Eight samples are to be tested from four locations, evenly spaced across the block. For a block to pass certification, seven of the eight samples shall meet the crush strength specification of the previous section.
3.  ADHESIVE BONDING PROCEDURE
3.1.  Immediately before bonding, aluminium sheet surfaces to be bonded shall be thoroughly cleaned using a suitable solvent, such as 1-1-1 Trichloroethane.
 This is to be carried out at least twice or as required to eliminate grease or dirt deposits. The cleaned surfaces shall then be abraded using 120 grit abrasive paper.
 Metallic/Silicon Carbide abrasive paper is not to be used. The surfaces shall be thoroughly abraded and the abrasive paper changed regularly during the process to avoid clogging, which may lead to a polishing effect. Following abrading, the surfaces shall be thoroughly cleaned again, as above. In total, the surfaces shall be solvent cleaned at least four times. All dust and deposits left as a result of the abrading process shall be removed, as these will adversely affect bonding.
3.2.  The adhesive should be applied to one surface only, using a ribbed rubber roller. In cases where honeycomb is to be bonded to aluminium sheet, the adhesive should be applied to the aluminium sheet only. A maximum of 0.5 kg/m2 shall be applied evenly over the surface, giving a maximum film thickness of 0.5 mm.
4.  CONSTRUCTION
4.1.  The main honeycomb block shall be bonded to the backing sheet with adhesive such that the cell axes are perpendicular to the sheet.
 The cladding shall be bonded to the front surface of the honeycomb block. The top and bottom surfaces of the cladding sheet shall not be bonded to the main honeycomb block but should be positioned closely to it. The cladding sheet shall be adhesively bonded to the backing sheet at the mounting flanges.
4.2.  The bumper element shall be adhesively bonded to the front of the cladding sheet such that the cell axes are perpendicular to the sheet.
 The bottom of the bumper element shall be flush with the bottom surface of the cladding sheet. The bumper facing sheet shall be adhesively bonded to the front of the bumper element.
4.3.  The bumper element shall then be divided into three equal sections by means of two horizontal slots.
 These slots shall be cut through the entire depth of the bumper section and extend the whole width of the bumper. The slots shall be cut using a saw; their width shall