Nathaniel Hawthorne Statue_Final Treatment Report_Fall 2017 Nathaniel Hawthorne Statue
Final Treatment Report
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Before Restoration After Restoration
Fall 2017
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Overview
Skylight Studios received confirmation on August 10, 2017 from the City of Salem that
we would be awarded the project based on our RFP submitted to complete the conservation of
the Nathaniel Hawthorne Statue. Our contract was signed and we submitted a Preliminary
Conservation Assessment report on September 5th, which outlined the existing conditions, the
history of the monument, and the proposed treatment. After acceptance of the Assessment, we
proceeded with the treatments at the Statue site from September 25th through October 1 Ith, 2017.
Further treatments to the stone were completed in November 2017. The following itemizes each
part of the completed treatment as well as specifications for recommended short- and long-term
maintenance.
Final Treatments
Granite
1. The granite base was cleaned using several applications of D/2 Biological Solution stone
cleaner. In between applications, a nylon scrub brush was used to remove ingrained dirt
(see pictures 4-6). In addition, it was washed several times with water through a low-
pressure power wash. Organic deposits, ingrained dirt, and some stains were successfully
removed. The areas of ingrained black stain caused by the bronze corrosion were
successfully removed by selectively air blasting with a fine sand from a distance of at
least one foot. See pictures 1-9.
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eforc;cleaning
After cleaning
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Picture 3 Application of D/2
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Picture 4 Scrubbing with Nylon Brush
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Picture 5 Scrubbing with Nylon Brush
Picture . Scrubbing with Nylon
Picture 7 Pressure
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Power
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Picture 8 Pressure Power Washing
Picture 9 Pressure Power Washing
2. The existing lead joints in between the component parts of the stone were checked for
stability. Areas of loose or missing lead were mechanically removed and repointed with
lead wool. The color of this material matches the existing lead.
3. In addition, at a later date the ingrained stains in the granite were cleaned with multiple
applications of Prosoco Sure Klean Restoration Cleaner diluted with water and a nylon
brush. The stone was then rinsed with water.
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Bronze
1. A double tower of pipe staging on all four (4) sides was erected around the monument.
The staging was used for access to all parts of the monument as well as acting as a frame
to make an enclosure with plastic that went up to the top of the sculpture. See pictures 10-
11.
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Picture 10 Pipe Staging
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Picture 11 Pipe Staging
2. Air blasting with fine sand was used to remove the existing corrosion from the surface of
the bronze. See pictures 12-13.
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Picture 12 After Air Blasting
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Picture 13 After Air Blasting
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3. The top surfaces of the bronze were mechanically highlighted with fine Scotch-Brite. See
pictures 14-17.
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Picture 14 During Highlighting
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Picture 15 During Highlighting
Picture 16 After Highlighting
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Picture 17 After Highlighting
4. Residue of sand and loose material was removed with compressed air.
5. The surface of the bronze was heated with a propane torch and multiple applications of
Ammonium Sulfide brown patina chemical diluted with water were applied by spray to
chemically renew the brown patina. After the last application, the sculpture was
thoroughly rinsed with water. See pictures 18-22.
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Picture 18 Patina Application
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Picture 19 ' pp •
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20 Heating with PropaneTorch
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Picture 21 Completed Patina
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Picture 22 Completed Patina
6. Two (2) applications of incralac diluted 30%with Xylene were applied by spray. See
pictures 23-28.
ApplicationPicture 23 During Incralac
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Picture 25 During Incralac Application
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Picture 26 After Incralac Application
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Picture 27 After Incralac Application
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Picture 28 After Incralac Application
7. Two (2) coats of microcrystalline paste wax were applied by China bristle brush. The
surface was buffed after drying with soft cotton rags and a horsehair buffing brush. See
pictures 29-32.
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Picture rt During Waxing
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Picture 30 After Waxing
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Picture 31 After Waxing
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Picture 32 After Waxing
8. The pipe staging was taken down and the site around the memorial was cleaned.
Maintenance Recommendations
Short-term Maintenance
1. An annual cleaning and re-waxing of the bronze is recommended. This will ensure
continued protection for the incralac coating and surface of the bronze to prevent
corrosion. The bronze should be thoroughly washed with multiple applications of running
water and soft sponges to remove all surface dirt which has accumulated on the surface.
If surface dirt remains, Vulpex soap diluted 10:1 with water can be applied with a soft
sponge manually and rinsed thoroughly with water. After cleaning it is necessary to
completely dry the surface of the bronze. This can be achieved with compressed air or a
portable leaf blower. A micro crystalline paste wax such as Butchers Wax, Trewax, or
BWC Bowling Alley paste wax is applied manually with a soft bristle brush to
completely coat the surface of the bronze. After the first coat has dried, a second
application should be applied. Once the wax has dried for a minimum time of 2 hours, the
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wax is buffed mechanically with soft cotton rags.Note: Re-waxing should be completed
over 2 days that have no precipitation and a relatively low humidity. The Spring or Fall
are optimum times to complete this treatment.
2. All mortar and lead joints should be inspected yearly and repointed if necessary.
3. The stone should be cleaned of organic matter and dirt as needed by applying D/2
Biological Solution. This biodegradable liquid cleaner removes biological and air
pollutant staining from many materials including stone and wood. It should be applied
with a brush or pump sprayer to a dry surface. After application, allow it to dry. Steps can
be repeated if necessary.
Long-term Maintenance
1. Over time, the incralac coating will break down and deteriorate due to the exposure of
ultra violet light. This may occur from within 6 to 10 years. This condition will be visible
by the appearance of a whitish flaking on the coating on the surface of the bronze. At this
time, the remaining wax coatings should be stripped mechanically with a solvent such as
Naphtha. After the wax is stripped, the incralac coating should be thoroughly stripped
mechanically with an organic paint stripper or solvent. At that time the stone should be
masked off and protected from potential run-off. Alternatively, it may be possible to
remove the existing incralac coating by use of a dry ice blaster. Once the incralac is
removed, the re-patination will still be intact. After thoroughly drying the surface of the
bronze, two new applications of incralac diluted 30%with Xylene should be applied by
spray. This should be followed by 2 new coats of microcrystalline paste wax applied with
a soft brush and buffed when dry.
Materials
Material sources for conservation and recommended maintenance are as follows:
1. Vulpex Soap is available through Talas,phone 212-219-0770, www.talasonfine.com.
2. D/2 Biological Solution is available at A.H. Harris & Sons, Inc., one location being in
Woburn, MA, as well as other retailers (www.d2bio.com).
3. Sakrete mortar patch is available at the Home Depot and other hardware stores.
4. Lead wool is available through Simply Plumbing, phone 866-786-3681,
www.simplyplumbing.com.
5. The solvents Naphtha and Xylene are available at the Home Depot and other hardware
stores.
6. Ammonium Sulfide is available through Triple-S Chemical Products, Inc.,phone 888-
417-5214, www.patinas.com.
7. Trewax is available at the Home Depot and other hardware stores and BWC Bowling
Alley Wax is available through the BWC Company, phone 800-569-0394,
www.bwccompan\.com.
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8. Incralac is available through Talas,phone 212-219-0770, www.talasonline.com.
9. Dry ice blaster is available at Continental Carbonic Products, 71 Linden Street, Lynn,
MA 01905, phone 800-379-4232.
This Final Treatment Report is submitted by:
Robert Shure &Kayla Malouin
Skylight Studios, Inc.
105 Salem Street
Woburn, MA 01801
on November 9, 2017
Revision submitted on November 30, 2017