Historic Preservation - Technical Procedures
Applying A Protective Coating To Brass-Plate And Solid Brass
Hspg Prepared For Nps - Sero
Applying A Protective Coating To Brass-Plate And Solid Brass
APPLYING A PROTECTIVE COATING TO BRASS-PLATE AND SOLID BRASS
ALL CLEANING REMOVES SOME SURFACE METAL AND PATINA. THEREFORE, USE
CAUTION, AS EXCESSIVE CLEANING CAN REMOVE THE TEXTURE AND FINISH OF
THE CLEANING OR STRIPPING OF METALS MAY INVOLVE THE USE OF
ABRASIVES, LIQUIDS OR SOLVENTS WHICH MAY SPLASH OR RUN OFF ONTO
ADJACENT MATERIALS. TAKE SPECIAL CARE TO PROTECT ALL ADJACENT
MATERIALS, AND DO NOT USE THIS PROCEDURE ON METALS OTHER THAN
SPECIFIED IN THE SUMMARY.
A. This procedure includes guidance on protecting brass-
plate and solid brass by applying a clear protective
coating such as tung oil, lacquer, or a commercial wax.
This procedure should follow thorough cleaning of the
B. For additional guidance relating to cleaning and
maintaining brass, see the following procedures:
1. For cleaning and polishing brass-plate, see 05010-03-P.
2. For cleaning and polishing solid brass, see 05010-10-P.
3. For removing old lacquer or paint from solid brass
or brass-plate, see 05010-31-R.
4. For removing patina or tarnish from solid brass,
C. Brass is an alloy of copper and zinc. Brass-plate is a
thin layer of brass bonded to steel. Solid brass is more
durable than brass-plate and, therefore, can withstand
more rigorous methods of cleaning.
D. Brass may be unfinished or lacquered. Architectural
brass hardware and trim is generally maintained in a
highly polished, "bright" finish.
1. Unfinished brass MUST be polished frequently in
order to maintain its luster. All polishing,
however, removes some brass.
2. Lacquered brass will usually last about 10 years
and does NOT require frequent polishing.
3. Lacquer protects the brass finish from
deterioration, though some brilliance of its
surface characteristics is sacrificed. Removal and
reapplication of the lacquer, however, will not
harm the brass surface.
E. See 01100-07-S for general project guidelines to be
reviewed along with this procedure. These guidelines
cover the following sections:
1. Safety Precautions
2. Historic Structures Precautions
4. Quality Assurance
5. Delivery, Storage and Handling
6. Project/Site Conditions
7. Sequencing and Scheduling
8. 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).
A. Stanley Chemical Co.
401 Berlin Street
East Berlin, CT 06023
A. Commercial wax or resin such as "Brasswax", or approved
"Slipit" silicone coating, or approved equal:
1. A lubricant containing silicone sold in hardware
stores for easing sticky windows, drawers, etc.
2. It is long-lasting, brass will darken only slightly
over many years.
Air-drying clear acrylic lacquer such as "Incralac"
(Stan Chemical Co), or approved equal.
B. Clean, potable water
C. Clean, soft cloths
A. Eye and skin protection
B. Heavy gloves and protective gear
C. Soft natural bristle brushes
A. Before proceeding with steps to clean brass, examine the
surface(s) to determine the extent of the work required.
1. Broken, cracked, missing, distorted or loose parts.
2. Coating failures such as chips, losses, peeling,
cracks, bubbling and wear.
3. Corrosion - caused by moisture, sea water and sea
air, deicing salts, acids, soils, gypsum plasters,
magnesium oxychloride cements, ashes, clinkers and
1. General: Comply with recommendations of
manufacturers of cleaners, polishes and coatings
for protecting building surfaces against damage
from exposure to their products.
2. Protect adjacent surfaces from contact with
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 porous surfaces.
3. Protect persons and surrounding surfaces of
building where metal surfaces are being restored,
from damage resulting from metal cleaning and
a. Prevent cleaning solutions and coatings from
coming into contact with persons and other
surfaces which could be damaged by such
b. Erect temporary protection covers over
walkways for persons who must be in area of
operations during course of metal cleaning and
c. Provide ventilation to eliminate the spread of
fumes to unaffected spaces.
B. Surface Preparation:
1. Before cleaning, determine if your brass surface is
solid or plated:
a. A magnet will stick to the steel beneath brass
plating; it will not stick to solid brass.
b. Solid brass can withstand much harsher
treatment than brass plating can.
3.03 ERECTION, INSTALLATION, APPLICATION
NOTE: WHEN CLEANING, TRY TO RETAIN THE BRASS PATINA, AS THIS
PROTECTS THE BRASS FROM FURTHER CORROSION.
A. Protecting Brass with Tung Oil:
1. If possible to remove piece, preheat oven to 150
degrees F and heat piece for 20 minutes.
2. Using a soft cloth apply tung oil, rubbing back and
forth and in a figure 8 pattern until only a thin
but even coat remains.
3. Dry for at least 4 hours before reinstalling.
B. Protecting Brass with Lacquer: Brass may either be
dipped or sprayed. DO NOT BRUSH ON COATING.
1. Apply coating within 4 hours of cleaning.
2. Apply coatings evenly to cleaned and polished brass
according to the coating manufacturer's written
3. For brass to be dipped: Dilute lacquer to a 50/50
solution with an appropriate lacquer thinner; dip
or spray brass with dilute lacquer; hang it up to
4. For brass to be sprayed: Use an automotive spray
lacquer and apply in 2 to 3 thin coats, from a
distance of about 8".
5. See also 05010-11-R for additional guidance on
applying a lacquer coating.
C. Protecting Brass with Commercial Wax: If pieces cannot
be removed, try using a commercial wax, such as
"Brasswax", or approved equal. Follow manufacturer's
A. During the work, remove from the site discarded cleaning
and coating materials, rubbish, cans and rags at end of
each work day.
B. Upon completion of coating work, remove all protective
coverings and coatings, and clean window glass and other
coating-spattered surfaces. Remove spattered coatings by
proper methods as recommended by coating manufacturer,
using care not to damage adjacent surfaces.
END OF SECTION