U.S. General Services Administration
Technical Procedures Disclaimer
Prior to inclusion in GSA’s library of procedures, documents are reviewed by one or more qualified preservation specialists for general consistency with the Secretary of Interior Standards for rehabilitating historic buildings as understood at the time the procedure is added to the library. All specifications require project-specific editing and professional judgement regarding the applicability of a procedure to a particular building, project or location. References to products and suppliers are to serve as a general guideline and do not constitute a federal endorsement or determination that a product or method is the best or most current alternative, remains available, or is compliant with current environmental regulations and safety standards. The library of procedures is intended to serve as a resource, not a substitute, for specification development by a qualified preservation professional.
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We’ve reviewed these procedures for general consistency with federal standards for rehabilitating historic buildings and provide them only as a reference. Specifications should only be applied under the guidance of a qualified preservation professional who can assess the applicability of a procedure to a particular building, project or location. References to products and suppliers serve as general guidelines and do not constitute a federal endorsement nor a determination that a product or method is the best alternative or compliant with current environmental regulations and safety standards.
PART 1–GENERAL
1.01 SUMMARY
A. This procedure includes guidance on cleaning and polishing unpainted ornamental metal surfaces and applying a new clear finish.
B. See 01100-07-S for general project guidelines to be reviewed along with this procedure. These guidelines cover the following sections:
- Safety Precautions
- Historic Structures Precautions
- Submittals
- Quality Assurance
- Delivery, Storage and Handling
- Project/Site Conditions
- Sequencing and Scheduling
- General Protection (Surface and Surrounding)
These guidelines should be reviewed prior to performing this procedure and should be followed, when applicable, along with recommendations from the Regional Historic Preservation Officer (RHPO).
1.02 QUALITY ASSURANCE
A. Mock-ups: Demonstrate materials and methods to be used for cleaning, paint stripping, and polishing for each type of ornamental metal surface and condition on sample panels of approximately 9 square feet in area. Test adjacent non-metallic materials for possible reaction with cleaning and paint stripping materials.
1.03 PROJECT/SITE CONDITIONS
A. Protect surrounding surfaces of building from damage resulting from ornamental metal restoration work.
B. Prevent chemical cleaning and paint stripping solutions from coming into contact with other surfaces which could be inured by such contact.
C. Dispose of by-products from cleaning and paint stripping operations by legal means and in manner which prevents damage to other surfaces.
PART 2–PRODUCTS
2.01 MANUFACTURERS
A. ProSoCo, Inc.
755 Minnesota Avenue
P.O. Box 1578
Kansas City, KS 66117
800/255-4255 or 913/281-2700
2.02 MATERIALS
A. Chemical Cleaner: Manufacturer’s standard strength acidic ornamental metal restoration cleaner, such as “Sure Klean 887 Stainless Steel Cleaner,” (ProSoCo, Inc.), or approved equal.
B. Protective Lacquer: Clear non-yellowing for protection of the finished metal surface.
C. Water for Cleaning: Clean, potable, free of oils, acids, alkalis, salts, and organic matter.
D. Cleaning Pads: No. 4/0 fine steel wool or synthetic pads.
2.03 EQUIPMENT
A. Brushes: Fiber bristle only.
PART 3–EXECUTION
3.01 PREPARATION
A. Protection:
- Comply with recommendations of manufacturers of chemical cleaners and paint removers for protecting building surfaces from exposure to their products.
- Protect glass, unpainted metal trim and polished stone from contact with acidic chemical cleaners by covering them with liquid strippable masking agent or polyethylene film and waterproof masking tape. Apply masking agent to comply with manufacturer’s recommendations. Do not apply liquid masking agent to adjacent painted or porous surfaces, use waterproof masking tape.
- Protect unpainted metal from contact with alkali chemical cleaners by covering them either with liquid strippable masking agent or polyethylene film and waterproof masking tape.
- Remove cellophane tape, masking tape, etc., from ornamental metal surface prior to cleaning.
3.02 ERECTION, INSTALLATION, APPLICATION
A. Brush apply chemical cleaner to ornamental metal surfaces in the concentration recommended by the manufacturer.
B. Agitate surface with either steel wool or synthetic cleaning pad. Follow direction of grain in metal. Do not scratch or abrade surface.
C. Thoroughly sponge or cloth rinse surface with clean water to remove chemical cleaner and loosened dirt.
D. Machine or hand polish metal where indicated with buffing wheel or soft cloth using polishing compound typically recommended as standard industry practice and as approved by the RHPO.
E. Repeat process as required to produce desired effect.
F. Wipe surface completely dry with clean soft cloths. Do not touch cleaned ornamental metal surfaces.
G. Immediately apply two coats of protective lacquer finish to surface.