Previously Re-Painted Plastisol & Pvf2 Cladding If a building has been previously re-painted with Steelseal or similar and the client wishes to further maintain or re-colour the cladding later on, Akzo Nobel can still provide a high performance re-paint system, within the Steelseal Product portfolio, incorporating a specially designed undercoat PC5AS, combined with the Steelseal Topcoat. Do Not apply the Standard Steelseal Primers - PC4VC or PC4WO to previously re-painted cladding. The identification as to whether a building has been repainted, if no records are available, can be quite a difficult task. If Steelseal has been applied correctly then pure visual evaluation is often insufficient, however possible indicators include surface brush marks around the cappings. It is often necessary to remove the top layer of the coating, Adhesion checks such as the St Andrews Cross cut test is often the best way of performing this, exposing any different coating layers or colours. Please note that as we are unable to give any assurances regarding the adhesion properties of the existing coating, we strongly recommend that you should contact Akzo Nobel Industrial Finishes for guidance. Suggested Specification for Previously painted Pvf2 cladding Thoroughly wash down with a suitable detergent solution so as to remove all dirt, chalk deposits, oil, grease, residues from sterilisation and any other deleterious matter. Fresh water rinse and allow to dry. Most common areas of corrosion occur at sheet ends/sides, overlaps and as a result of mechanical damage. Remove corrosion by mechanical abrasive tools to achieve a bright metal substrate feathering back adjacent sound Plastisol. Any white zinc salts must also be removed by dry abrading using nylon scouring pads or similar. Remove any ‘lift & curl’ Plastisol at the bottom of the sheets where necessary, by mechanical means, and feather the edges back to a sound basis Remove all loosely adhering coatings back to a firm sound basis and feather back all edges. (The success of the overpaint will be attributed to the diligence of this preparatory work.) Abrade the firmly adhering coatings to check its adhesion and provide a ‘Key’ for the subsequent coating Ensure all surfaces are clean, dry and free from oil, grease or other deleterious matter before painting commences. PAINTING Apply Overall 2nd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60 mms * 3rd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60 mms * The second topcoat requirement, will depend on the colour choice, method of application, profile detail and access, and will ensure obliteration and maximum opacity. Please note we are unable to give any assurances as to the adhesion of existing coatings. Consideration should be given to surface profile, accessibility, location and equipment used. Work should be carried out using good painting practices and application techniques to ensure that a continuous, even wet film is applied. Pigment orientation of metallic shades can result in sueding effects if applied incorrectly. The above suggestions are given in good faith, without prejudice or liability, and all materials should be applied in strict accordance with the product data sheets and Steelseal Repaint Systems - Notes for Guidance. This specification is valid for 6 months from the date of the document. Further deterioration in site conditions may occur after this time, which would require a new specification. All materials are subject to Akzo Nobel Industrial Coatings Ltd Current Terms and Conditions of Sale.
Suggested Specification for Previously painted Plastisol cladding PREPARATION Thoroughly wash down with a suitable detergent solution so as to remove all dirt, chalk deposits, oil, grease, residues from sterilisation and any other deleterious matter. Fresh water rinse and allow to dry. Most common areas of corrosion occur at sheet ends/sides, overlaps and as a result of mechanical damage. Remove corrosion by mechanical abrasive tools to achieve a bright metal substrate feathering back adjacent sound Plastisol. Any white zinc salts must also be removed by dry abrading using nylon scouring pads or similar. Remove any ‘lift & curl’ Plastisol at the bottom of the sheets where necessary, by mechanical means, and feather the edges back to a sound basis Remove all loosely adhering coatings back to a firm sound basis and feather back all edges. (The success of the overpaint will be attributed to the diligence of this preparatory work.) Abrade the firmly adhering coatings to check its adhesion and provide a ‘Key’ for the subsequent coating Ensure all surfaces are clean, dry and free from oil, grease or other deleterious matter before painting commences. PAINTING Apply Overall 2nd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60 mms * 3rd Coat: Steelseal Topcoat, PC5VF Series, DFT 50-60 mms * The second topcoat requirement, will depend on the colour choice, method of application, profile detail and access, and will ensure obliteration and maximum opacity. Please note we are unable to give any assurances as to the adhesion of existing coatings. Consideration should be given to surface profile, accessibility, location and equipment used. Work should be carried out using good painting practices and application techniques to ensure that a continuous, even wet film is applied. Pigment orientation of metallic shades can result in sueding effects if applied incorrectly. The above suggestions are given in good faith, without prejudice or liability, and all materials should be applied in strict accordance with the product data sheets and Steelseal Repaint Systems - Notes for Guidance. This specification is valid for 6 months from the date of the document. Further deterioration in site conditions may occur after this time, which would require a new specification. All materials are subject to Akzo Nobel Industrial Coatings Ltd Current Terms and Conditions of Sale.
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