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Application Guide - Above Waterline Application Systems

Surface Preparation and Priming - Steel Hot & Cold Rolled

Blasting

  1. Thoroughly clean and degrease the surface. Use commercial detergents, steam cleaners or pressure washers. Be sure all detergent residues are rinsed from the surface. Use Awlgrip Wipe-Down Solvent (NA/AP: Awlprep Plus T0115; EU: Surface Cleaner T0340) as a final wipe down of the surface.

    Important

    Plan your work schedule carefully! Any area which is ground or blasted must be primed during the same work shift, preferably within 4 hours.
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  1. Grit blast to white metal in accordance with SSPC–SP5–85 (Sa2½) to a 2–3 mils (50–75 microns) profile. If profile is particularly jagged, grind to remove "spikes," providing a more uniform surface.
  2. Blow off the surface thoroughly with clean, dry compressed air or vacuum to remove all blast/grind/sanding residue and any dust or dirt. Use a brush or broom if necessary.

    Caution

    Do not use rags to clean this surface. The sharp metal will snag fibers from the rags. These fibers can act as wicks for moisture or other contamination to enter the paint film. This can lead to premature failure of the Awlgrip Coating System.

    To hold your surface preparation and prevent the need to repeat this work, the substrate should now be primed as detailed below.

    Tip

    For the ultimate anti–corrosive scheme first prime the prepared steel with Max Cor CF.
    Note: This must be during the same work shift, preferably within 4 hours after the final surface preparation. Spray apply Max Cor CF in one full wet coat to approximately 0.8–1.4 mils (20–34 microns) wet film thickness to achieve 0.6–1.0 mils (15–25 microns) dry film thickness.

    Important

    Allow to cure for a minimum of 17 hours.


  3. Apply Hullgard Extra by roller or spray.
    Note: Only apply Hullgard Extra by roller if applying over Max Cor CF due to risk of snagging roller fibers. For spray application, apply 9 mils (220 microns) wet film thickness to achieve 4 mils (100 microns) dry film thickness. Allow a minimum drying time of 3 hours at 68°F (20ºC) before proceeding.

Roller application will require at least two coats to achieve 4 mils (100 microns) dry film thickness. Allow a drying time of 3 hours at 68°F (20ºC) between coats.

Depending upon the conditions it may be possible to proceed to filling and surfacing without the need for sanding the substrate primer (see Fairing and Surfacing section for detailed information).

Please consult product datasheet for further details.


Grinding

  1. Thoroughly clean and degrease the surface. Use commercial detergents, steam cleaners or pressure washers. Be sure all detergent residue is rinsed from the surface. Use Awlgrip Wipe­-Down Solvent (NA/AP: Awlprep Plus T0115; EU: Surface Cleaner T0340) as a final wipe down of the surface.

    Important

    Plan your work schedule carefully! Any area which is ground or blasted must be primed during the same work shift. Preferably within 4 hours.


  2. Grind with 36 grit disc to bright, clean steel. The metal must be bright silver, completely free of gray oxidation. The surface profile must be a 2–3 mils profile (50–75 microns).
  3. Blow off the surface thoroughly with clean, dry compressed air or vacuum to remove all grind/sanding residue and any dust or dirt. Use a brush or broom if necessary.

    Caution

    Do not use rags to clean this surface. The sharp metal will snag fibers from the rags. These fibers can act as wicks for moisture or other contamination to enter the paint film. This can lead to premature failure of the Awlgrip Coating System.

    To hold your surface preparation and prevent the need to repeat this work, the substrate should now be primed as detailed below.

  4. Apply Hullgard Extra by roller or spray.
    Note: This must be during the same work shift, preferably within 4 hours after the final surface preparation. For spray application, apply 9 mils (220 microns) wet film thickness to achieve 4 mils (100 microns) dry film thickness. Allow a minimum drying time of 3 hours at 68°F (20ºC) before proceeding.

Roller application will require at least two coats to achieve 4 mils (100 microns) dry film thickness. Allow a drying time of 3 hours at 68°F (20ºC) between coats.

Depending upon the conditions it may be possible to proceed to filling and surfacing without the need for sanding (see Fairing and Surfacing section for detailed information).

Please consult product datasheet for further details.

Hotworks on the steel will damage the Hullgard Extra primer; please check with your local Technical Sales Representative for the appropriate repair guidelines.


Alternative Steel Systems

In some circumstances a full anti-corrosive/fairing system may not be required (e.g. window frames, parts etc). In such instances there is an alternative option for coating the suitably prepared steel— a Build System. Below details the surface preparation for the system.

Build System

  1. Grind the substrate as per steps 1–3, p33 or blast the substrate as per steps 1–3, p32.
  2. Apply by air atomized spray 1 coat of Wash Primer CF at 2 mils (50 microns) wet film thickness giving a dry film thickness of 0.25 mils (6 microns). Several passes are required with the spray gun for a good surface. The first pass should be relatively slow (5–10cm / 2–4 inches per second). This pass is to obtain basic coverage.

    Following sanding, if necessary, surface is now ready for final prime and topcoat application.

Important

While the build system will be touch dry at 24 hours at 77°F (25°C) following topcoat application, it’s important for the ‘controlled fusion’ to fully activate and through dry. No assembly, stacking or drilling should take place prior to 2 weeks at 77°F (25°C), or 3 weeks at 55°F (13°C).