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0. Choosing a finish, corrosion
• Options for using tin plated terminals above the rated temperature? - March 7
• Galvanic Action between Galvanized and Stainless Steel? - February 8
• Want gold colored finishes without use of gold - February 5
• Salt spray or CASS hours for electrophoretic lacquer on PVD on nickel plating - January 24
• Which coating is suitable to 1440 hrs SST open Q. - January 17
• Need to know steel mill that produces Corten Steel open Q. - January 10
• White flow marks caused by new PT line - January 5
• How to Achieve Zinc Rainbow Patina - October 15
• How to restore mirror finish on stainless steel - October 4
• What ferrous material is fully resistant to hydrochloric acid?
- September 28
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1. Preparation
1a. MECH PREP topics: "Grinding, polishing, vibratory finishing, buffing, honing"
• Stainless steel vibratory finishing Q&A open Q. - March 1
• Repair brushed stainless finish
open Q. - October 31
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1b. CHEM PREP topics: "Cleaning, pickling, etching, phosphatizing, activation"
• Testing the concentration of titanium phosphate bath open Q. - March 16
• Dry Acid salt for brass and Zamak parts open Q. - March 3
• Zinc phosphate coating is black and peels off - February 5
• Removing carbon layer from mild steel - February 2
• Electrocleaning of Nickel - January 4
• Pickling solutions for copper & brass - November 25
• How to determine whether component is zinc phosphated or manganese phosphated open Q. - November 5
• Oil Leaking on Hydraulic Pump after Pretreatment open Q. - October 24
• What chemical for matting or etching acrylic (poly methyl methacrylate) sheet? open Q. - October 14
• Manganese Phosphate coating problem on nitrided parts
- October 14
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1c. Capping, plugging, masking, taping
• Masking/Stop off for anodizing on complex parts - January 24
• How to mask workpiece holes in black anodizing? - November 14
• Plating of stainless steel tube damages inside surface
- October 27
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2. Metallic & inorganic finishes
2a. STAINLESS, TITANIUM, CORROSION-RESISTANT METALS PROCESSING
• Adding water to electropolishing solution raises normality, doesn't reduce it open Q. - March 17
• Must welding tint be removed before passivation - March 7
• Stainless tank with NaOH at 360 °C at 128 bar - February 27
• Electropolishing and Chemical Etching Processes for Cobalt Chromium - February 5
• Chatter-like marks after electropolishing? - February 2
• Can T316 stainless steel be used 400 feet away from the sea? - November 9
• SS420 Pickling and Passivation Problem - October 25
• Need consultant for AMS2488 Type II Anodizing of Titanium RFQ open to all: Miami - October 19
• Passivation for type 420SS stainless - October 15
• Citric Acid vs. Nitric Acid Passivation
- October 3
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2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• Mirror polishing thin aluminum sheet on both sides without warping - March 10
• Black Marks on Extruded Aluminum I-Beams - March 7
• Problems in cold sealing of anodized aluminum - March 2
• Halo spot in Hard Coating 6061-T6 Aluminum - February 22
• Two-step" black anodizing has reddish powder on it open Q. - February 19
• Trouble with Iridite 14-2 only on 2024 - February 19
• White patches only when anodizing 60xx open Q. - February 19
• Hard anodizing chiller sizing - February 15
• Anode to Cathode Ratio, Size, Spacing, Placement in Anodizing - February 12
• Dye keeps flaking off along with some of the anodize open Q. - February 2
• Methods for evaluating surface preparation steps during the anodizing process open Q. - January 29
• Hard Anodizing Defects: stains, flow marks - January 27
• White spotting on black (and red) anodising open Q. - January 11
• Calculating required aluminum anodizing time - January 11
• Electrolytic Etching of Aluminum open Q. - January 10
• Aluminum Anodizing Color Match Problems open Q. - December 30
• White spots in black anodizing open Q. - December 29
• Large Plate anodizing problems - December 27
• Contaminant Build up in Anodize Line Rinse Tanks open Q. - December 13
• Hard anodized parts are matte & dull; should be smooth & shiny - December 11
• Black rubs off anodized parts - November 25
• Problems in Plating on Aluminum, including alloy selection - November 21
• Sealing Aluminum to prevent oxidation? - November 9
• Snowflake corrosion on Duranodic anodized parts - October 25
• Dissolving aluminum with caustic soda - October 24
• Black anodize gets white stains only on large sheets - October 22
• Minimum time between chem-film and priming - October 22
• Re-anodizing Aluminum which has been previously anodized - October 19
• Trying to mild etch High Mg Al alloy open Q. - October 8
• Water quality / chloride contamination in anodizing open Q. - October 5
• De-smutting/De-Oxidizing of aluminum
- October 3
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2c. ELECTROPLATING and ELECTROFORMING
• Zinc plating thickness vs. salt spray resistance open Q. - March 10
• Complete Process for Cleaning, Cu, and Ag Barrel Plating on Stainless Steel - March 3
• Classification for evaluating corrosion in salt-laden atmosphere open Q. - March 1
• Nickel & Gold Plating peels off of Tungsten-Carbide - March 1
• Zinc plating with blue passivation is yellowish at holes - February 29
• Voltage spikes and amperage drops in Cu-Sn plating - February 27
• Copper exposed on parts that are supposed to be nickel open Q. - February 26
• Oil mark issue in satin nickel plating open Q. - February 25
• Spotted cadmium open Q. - February 19
• Tin plate Blistering - February 19
• Hard chrome plating problems - February 19
• Zinc plate steel wire then draw it, or draw it then plate it? open Q. - February 19
• Zinc Plating has white & red rust without a cause - February 19
• Expired Lead Frame effect on Plating Quality open Q. - February 2
• Scratches on Hydraulic Cylinders: Mechanical Damage or Plating Defects? - February 1
• Alkaline zinc plating thickness - January 24
• Blue spot/growth on a silver plated component open Q. - January 16
• Black stain spots in satin chrome, plus burning open Q. - January 14
• Surface Area Calculations for Rough Castings - January 4
• Problems copper plating gravure cylinders open Q. - December 31
• The Role of sulfuric Acid in Copper Plating - December 30
• Silver Plating brighteners Q&A open Q. - December 22
• Formula or recipe of Zinc brightener - December 18
• Removing discoloration patches from nickel plated brass - December 13
• Repair of hard chromium plated parts open Q. - December 11
• Acid Zinc Plating turns gray in 3 months - December 9
• Brass Hull Test Panel Cathode Cleaning - December 8
• Silver plating with Auxiliary Anodes - December 8
• Is Flash Gold / Colour Gold long lasting? - December 7
• Need silver plating on 13K per year 2" dia x 73" long aluminum bars RFQ open to all: Jackson, MS - December 6
• Adhesion No Good for Nickel Plating on Neodymium open Q. - December 1
• Zn25 vs ZnNi12 - Expected lifetime for marine indoors open Q. - November 27
• Zinc-Nickel Plating and Chromating Problems & Solutions open Q. - November 21
• Carbon treating silver plating solution with activated carbon cartridges open Q. - November 21
• Roughness in copper-nickel plating on zamak - November 13
• Tin Plated Parts are Turning Black open Q. - November 11
• Cadmium Cyanide adhesion issue open Q. - November 8
• Chrome plating and coefficient of expansion - November 8
• Want to find an alternative chrome plating process - November 1
• Unusual behaviour of thief wire in chrome plating open Q. - October 25
• Chrome plated engine valves nodular and peeled in one area open Q. - October 23
• Brass plating is tarnishing and turning black open Q. - October 22
• Black Passivation and Black Trivalent Plating - October 22
• Cyanide spots and stains in brass plating - October 15
• Facing issues with air locks! - October 14
• Chrome rods on hydraulic cylinders show lateral lines ... mechanically induced? - October 14
• Zinc-Nickel Plating very thin in some area of padbolts open Q. - October 14
• It takes an hour to zinc barrel plate in ammonia chloride open Q. - October 11
• Do We Use DuNuöy Ring or Wilhelmy Plate Tensiometer for Chromic Acid? open Q. - October 8
• What are these crystals on cadmium plated parts?
- October 7
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2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• Silvering formulas using silver nitrate - March 3
• Electroless copper plating onto wax - November 25
• Best Bright Chrome effect paint for polystyrene plastic open Q. - November 2 Inquirer often helps others, so especially deserves our help
• Random parts are not plating completely in electroless nickel open Q. - October 22
• Conductive paint for plating on plastic, flowers, glass, non-conductors open Q. - October 20
• RCA test for electroless nickel
open Q. - September 27
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2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
• Need TiN coated stainless sheets RFQ open to all: Las Vegas NV - February 20
• Red chromium by PVD sputtering? open Q. - December 19
• PVD coatings: color control Q&A's, Problems & Solutions open Q. - December 2
• Ion nitriding problem: batch with white dot colorization open Q. - September 29
• PVD coating directly on hot dip galvanized steel - September 27
• Need to pre-coat polyester fabric for PVD aluminum coating
open Q. - September 18
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2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
• Galvanizing buildup on MIG wire weld areas - March 11
• How much hydrogen peroxide to treat flux tank? - March 11
• Spotting, Staining, Blackening of Hot Dip Galvanized Finish - March 10
• Having trouble heating the flux bath - March 1
• Cost to open a hot dip galvanizing business? - February 20
• Zinc ammonium chloride requirements for galvanizing flux - February 19
• How tough is galvanneal steel? Will it rust if the coating is penetrated? - February 5
• Top Dross is growing since we started filtering open Q. - January 17
• Need MIG or SAW Wire for Fabrication of Galvanizing kettle RFQ open to all: Gujarat, India - December 13
• Hot-Dip Galvanizing Kettle: how to build or where to buy one - December 1
• Galvanizing surface area and weight gain don't match up - September 28
• How to dull (reduce shine of) galvanized sheets & roofs - September 26
• Heating a galvanizing kettle with lead jacket
open Q. - September 23
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2g. BLACK OXIDE, BLUING, COLORING, PATINAS, NITRIDING
• Hot Black Oxide Issue- brownish-green parts and black spots/streaks - February 12
• Smut on the black oxide coatings - December 7
• Blackening gold with iodine
- June 17
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2h. OTHER INORGANIC FINISHING: Mechanical Plating, QPQ, Metal Spray, Zinc-rich Dip-Spin Coatings, Sherardizing, Rust Preventatives, etc.
• Rust spots on pickled coil after a few days open Q. - September 1
• Sursulf Processing Q&A, Problems & Solutions open Q. - April 4
3. ORGANIC FINISHING [PAINT, POWDER COATING] . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
• Misc. problems in CED (cathodic electrodeposition) coating open Q. - March 4
• Electrodeposition/e-coating (CED) issues & problems - December 8
• Paint ooze out in CED process open Q. - November 21
• How to Increase DFT Paint Thickness in Cathodic Electrodeposition (CED) system? - November 11
• CED E-coat air pockets/air trapping
- October 2
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3b. POWDER COATING
• Pinhole problems in powder coating - February 13
• L.a.b. CIELAB color issues: gloss variation, matching different finishes, etc. - February 4
• Powder Coating of "Black Annealed" CRS - January 3
• Powder Coating Failed Salt Spray Test - December 8
• Laser printing powder coated steel open Q. - November 20
• Is "pre heating" essential for powdercoating? open Q. - November 8
• Need 4 chrome wheels stripped & powder coated
RFQ open to all, Pompton Lakes, NJ - October 13
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3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
• Protecting metal surface with thousands of tiny grooves that trap dirt - March 1
• Solvent name for reducing the pH of electrophoretic bath open Q. - February 2
• Need longer-lasting lacquer for gold plating
open Q. - September 11
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3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• Gluing Stainless steel to chrome/copper/alloy plate - March 5
• Sublimation Coating Introduction, FAQs and Q&A open Q. - February 23
• Plastisol & Solvent Ink Formulas & Improvements - February 5
• Painting anodized aluminum - February 1
• What is the color of the Nose Wheel Well Spin Brake Spring? open Q. - December 16
• Need "splatter" painting in trunk of '60s GM car RFQ open to all: Coeur d'Alene, ID - December 6
• How many micron thickness reduction after rub test on painted panel? open Q. - October 25
• Will paint withstand while moving a vehicle top of it open Q. - September 14
• FBE Pipeline Coating Issues
open Q. - September 12
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4. POST-TREATMENTS
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
• Can zinc plated parts go on for zinc phosphating? - February 4
• Verifying anti-tarnish for copper plating open Q. - January 13
• Trivalent passivation yellow or iridescent
open Q. - July 29
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4b. BAKING AND NON-CHEMICAL POST-TREATMENTS [HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]
4c. STRIPPING, REWORKS, ETC.
• How to strip nickel from copper plate open Q. - March 5
• Need paint stripper not harmful to plastic open Q. - March 3
• Stripping electrophoretic CED coatings open Q. - February 2
• Removing/Stripping Electroless Nickel Plating from Steel - December 19
• Cyanide vs. Non-Cyanide Electroless Nickel Stripper - December 4
• Plating was stripped from 4340 steel parts; no etching/pitting at the time, only days later open Q. - November 21
• Remove dried plating salts that leaked into cavities open Q. - November 8
• How to strip hard chrome at home - November 8
• Remove/strip anodizing from aluminum
- October 13
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5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
• XRF and Plating Thickness Measurement open Q. - March 7
• ASTM B117 Salt Fog Test Chamber Operational Q&As, Problems: Salt Spray Woes open Q. - March 3
• Copper Sulphate Test on Gold Plated Part open Q. - March 1
• Acceptance criteria after salt spray test - February 19
• Need lab SOPs for electroplating shop - February 16
• Is titration the best method to analyse copper content of ore? - February 5
• Determine % Nitric Acid. Titration? Conversion factor? open Q. - January 29
• Test for Type 316 vs. 304 Stainless Steel open Q. - January 9
• Analyzing acid tin baths -- bright and matte open Q. - January 9
• Salt Spray and Cyclic Corrosion Test for Assembled Parts January 4
• How to Analyze for Iron in Deox and Anodize tank? - December 4
• Hydrogen Embrittlement Test Failure open Q. - November 21
• Noüy Ring vs. Withelmy Plate Tensiometer for Chrome Surface Tension open Q. - November 9
• Water immersion test for stainless steel passivation Q&A, Problems & Solutions - October 8
• How to perform Acid MEQ of CED Bath manually? - October 8
• Analysis of ammonium nitrate in stripping solution
- October 2
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5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• Recovery of copper from electroforming solution - January 7
• How to treat BOD and COD in finishing wastewater - December 21
• How to deal with galvanizers waste acids open Q. - December 13 Inquirer often helps others, so especially deserves our help
• Change Hexavalent to trivalent chrome? Chrome Reduction process - October 11
• Ion Exchange / DM plant calculations
open Q. - September 6
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5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
• Has anyone been diagnosed with Parkinsons after working in the chrome plating industry? open Q. - March 10
• What is the toxic effects of mixing muriatic acid and bleach? - March 4
• Cyanide Poisoning Issues - February 2
• Toxic Lead & chrome in coffee makers & espresso machines? - January 13
• How to remove chrome stains from hands & arms? - December 17
• Are galvanized steel tub and dish okay for my dogs to drink from? - December 17
• Danger in Cast Aluminum Cookware? open Q. - December 7
• Health issues in welding on galvanized steel - November 10
• Must silver plated parts be watched for cyanide? open Q. - September 27
• Painting galvanized stock tanks, and use as a swimming pool or hot tub?
open Q. - September 7
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5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• Production of silver potassium cyanide from silver nitrate open Q. - January 23
• Long parts bend during barrel plating - November 21 Inquirer often helps others, so especially deserves our help
• Ampacity & sizing of Aluminium busbar - November 21
• Will the low conductivity of Titanium be a problem? - October 18
• Need 20 Liter divided electroplating tank with an Anion membrane RFQ open to all, Palm Springs, CA - October 16
• Chilling of temporary anodising bath on the cheap - September 18
• Chem supplier for small biz
RFQ open to all, Alpine, CA - September 15
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5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, HISTORY, ETC.
• What is Alcoa Alumilite Black 326R1? open Q. - March 1
• What is the meaning of MFZn1-SC open Q. - October 17
• Does MIL-C-5541 forbid a "Do Not Etch" instruction? - January 26
• FAIR 9102 Question re. Chromating & Anodizing - January 19
• Salt spray test: Organic thread coating makes plated fasteners rust open Q. - November 15
• Seeking MSDS and TDS for Novamax products - November 1
• Rectifier calibration open Q. - October 27 Inquirer often helps others, so especially deserves our help
• DFAR prohibits "hexavalent chromium in a concentration greater than 0.1 percent" - October 19
• Verifying a Bond Path Analysis equation?
open Q. - September 26
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5f. W...W...W...WORD OF THE WEEK
• Procedures QF-09-162 & QF-09-163 for nitric & chromium analysis? open Q. - March 10
• Converting "baumé" to Concentration
- September 25
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5g. MOSTLY METALLURGY; Heat Treatment
• Annealing 316 Stainless Steel Tubing - March 1
• How to demagnetise stainless steel? - October 18
• 316L Stainless Steel is too springy open Q. - October 16
• Sometimes in hot rolling the Mill Scale is excessive open Q. - September 12
• Yellow stains on heat treated stainless steel
open Q. - September 10
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5h. PRECIOUS METAL RECOVERY
• Is this ore/rock Palladium & Rhodium open Q. - March 1
• Recovery of fine floating gold open Q. - January 27
• How to separate copper from silver - January 11
• Can gold be reclaimed from old ceramic dishes with gold trim - December 14
• Recover Gold from Vintage Italian Murano Gold Infused Lamp open Q. - December 2
• Acid testing for gold, silver & precious metals
open Q. - October 8
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6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
• Electroplating as forge welding prep - March 11
• Oxide Finishing - March 3
• Brass lamp seems to be brass plated copper - February 12
• Have Blue Gun, Want it Chrome appearance open Q. - February 8
• Ruined the finish on my stainless steel fridge - February 8
• How to Remove Zinc Phosphate from Frying Pan - January 20
• Sticky surface after anodising - January 19
• Remove black antiquing from my Citadel class ring open Q. - January 18
• Jewelry cleaner took finish off ring - January 7
• "Rainbowing" and "Bluing" Stainless Steel - January 7
• Bright Dipping of Brass Q&A - December 21
• Need to reapply silver / gold rims onto crystal stemware - December 21
• Removing Paint from Vintage Chandeliers & Candelabras - December 19
• Repair enamel coated steel tea kettle? open Q. - December 11
• Need Rechroming of Drum Hoops & Lugs RFQ open to all: Lufkin, TX - December 8
• Electroforming with Brass - November 27
• How to Dull Bright WW2 German Dagger open Q. - November 25
• Silver tarnishing -- is body chemistry responsible? open Q. - November 20
• F.B. Rogers Silverplate Q&A's? - November 11
• Painting cast iron fountains / restoring rusty fountains open Q. - November 10
• Wearing gold rings & jewelry turns my skin black - November 8
• Pre-coating for sublimation transfers onto ceramic open Q. - November 1
• Brass is Pink not Yellow - October 27
• Can't color Zinc/Zamac/Pot Metal gun parts open Q. - October 24
• How to Rust corrugated steel open Q. - October 24
• Removing Silica Water Stains open Q. - October 24
• Remove rust with muriatic acid (HCl / hydrochloric acid) open Q. - October 21
• Cleaning copper roofs - October 15
• Metal Gaming Chair Finish open Q. - October 14
• Washing machine broken aluminum spider arm? What coating needed? open Q. - October 14
• Need Noxon 7 Metal Polish - October 14
• Not succeeding with ultra-black Ruthenium plating open Q. - October 12
• Plating leaded stained glass open Q. - October 11
• Damaged finish on copper table
open Q. - October 3
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6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
• Achieve uniform thickness in Cobalt-platinum electroplating - February 15
• Electroplating with copper sulphate for science project - December 26
• Electroplating on complex geometry, a microlattice structure
December 4
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6c. K-12 Science Projects, Grammar & High School Student Questions
• Electroplating with copper sulphate for science project - February 24
• To rust and trust -- school science experiments with rust - November 21
• How Much Does a Penny Weigh? open Q. - August 18
• How to convert from v/v to w/v if specific gravity is given?
- August 13
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6d. The Artists' Corner
• Antique French cast metal lamp figurine is what metal? - January 14
• Copper electroforming is too red - January 4
• Hand painted art on a vehicle open Q. - September 11
• How to clean/restore C Jere metal sculpture
open Q. - September 9
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7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
• Who invented words? - March 14
• Remove Brown "Varnish" (periostracum) from Shells open Q. - March 7
• About sweet spirits of nitre (the traditional folk medicine) - February 22
• Bleaching Saguaro (Cactus) Skeletons - February 22
• Normal weight 2015d nickel shrunk to size of a penny open Q. - February 2
• Identifying rings/hallmarks - January 27
• Is 'P star M' ring that's marked 14K actually solid gold? - January 29
• Stiffel lamp Q&A's open Q. - January 22
• Brass Finishers in the 1800's / 19th century open Q. - January 13
• Barber Chair doesn't go up or down open Q. - December 29
• Need iron in diet -- will steel water bottles do it? - November 20
• What chemical would a master plumber use that would cause heat when in contact with water? open Q. - November 11
• Theda Sterling Silver Medals, Crosses, Jewelry Q&A - November 11
• Antique icebox Q&A's, Problems & Solutions - November 9
• Maker's mark on Spanish gothic chandelier open Q. - November 9
• Toxic effects of boric acid on feral cats open Q. - November 7
• Home Comfort Parts Needed RFQ open to all: California - October 27
• Monarch Stove Parts Needed RFQ open to all: Kentucky - October 27
• FB Rogers engraved silver plated pitcher open Q. - October 22
• Black Powder Cannons open Q. - October 17
• Boric acid, etc. for dog ear infections - October 14
• Bleach (sodium hypochlorite) attacking steel hull boat
open Q. - October 7
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