It is important that the surfaces to be coated are suitable prepared or soundproofing characteristics may be impaired. Surfaces must be clean and degreased. Pre-painted or stainless steel surfaces should be mechanically keyed by rubbing with emery cloth. Freshly galvanised metal must be treated with a Mordant solution. For aluminium, use an etching primer. Other unpainted metal surfaces should be treated with a single coat of a quality matt primer.
The maximum wet thickness of compound which can be applied to vertical surfaces is approx. 3mm (4.5kg/m2 wet weight). Greater thicknesses can be built up by successive coats but complete drying of each coat between applications is essential. If the product is to be trowelled onto other than horizontal surfaces, a keying coat of diluted compound should initially be brush applied and allowed to thoroughly dry before applying the main body of compound. Whichever application method is used, all drums of compound must be thoroughly stirred before use with a low speed electric stirrer.
The material can be pumped using either a Pressure Pot or 4:1 ratio pump (with sand kit). Both require a minimum compressed air supply of 20cfm at 650psi. The material delivery hose must have a minimum internal diameter of 0.75" (18mm). The spray gun should be of the air-mixture type with 0.25" (6mm) internal diameter nozzle The maximum application rate with the above equipment will be approx. 3kg per minute.
Drying times depend on the compound thickness and ambient conditions. Examples of typical drying times are shown below.
| OVEN DRYING TIME (HOURS) | AMBIENT DRYING TIME (HOURS) | |||||
| Wet application Weight | Temp oC | For Safe Handling | For Max. Damping | Wet application Weight | For Safe Handling | For Max. Damping |
| 2kg/m2 5kg/m2 |
110 100 |
0.25 1 |
0.5 2.5 |
2kg/m2 5kg/m2 |
2.5 12 |
5.5 29 |
treatment with a thicker layer significantly increases drying times.
ACOUSTICAULK™ is resistant to but not proof against, absorption of fluids eg. oil or water. Excessive exposure to such fluids will lead to softening of the material and loss of acoustic performance. Protection can be provided by thoroughly overpainting after drying with several coats of paint. For protection against exposure to weather, several thick coats of bituminous paint should be used to completely seal the compound.
ACOUSTIC PERFORMANCE. The soundproofing damping efficiency of ACOUSTICAULK™ depends upon the ratio of the thickness of the damping layer to the substrate and the operating temperature. The graphs shown on the Technical Data page show the relationship between these two factors and the damping efficiency of the compound when it is applied to a steel substrate.