Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
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The authoritative public forumfor Metal Finishing 1989-2025
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0. Choosing a finish, corrosion
172/59. Gold Plating a Kalash - 1/7/25
617/67. Looking for the hardest, unscratchable finish for jewelry RFQ: Idaho - 1/6/25
354/05. Copper/Aluminum interaction and galvanic/hydrolysis problems - 12/12/24
106/55. Tantalum Coating Processes - November 23
617/72. Choosing a metal finishing process - November 15
121/17. Deposition of Aluminum onto Steel then Anodizing - October 30
241/10. PVDF / Kynar® vs. Powder coating - October 29
277/02. Corrosion of silver caused by ZDDP (zinc based lubricant additives) - October 28
617/60. Zinc Plate vs E-Coat - October 22
221/43. 316 Stainless Shaft Gets Grooved by Radial Seals - September 25
451/29. Anodizing vs. Powder Coating of Aluminum? - August 28
617/05. Matching Finishes between Aluminium and Copper Parts
- August 24
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1. Preparation
1a. MECH PREP topics: "Grinding, polishing, vibratory finishing, buffing, honing"
525/93. Best Buffer RPMs for Polishing Aluminum? - 12/22/24
617/23. Mirror polishing very small hardened steel components - 9/25/24
617/15. Shot blasting for acidic electroplating - 8/21/24
617/08. Spots on steel parts from tumbling
- 9/19/24
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1b. CHEM PREP topics: "Cleaning, pickling, etching, phosphatizing, activation"
09/60. Best way to blacken zinc phosphate - 12/30/24
340/52. Manganese phosphate coating: issues and answers - 12/29/24
617/76. Mixed metal pretreatment configuration - 12/9/24
14/04. Electropolishing of silver - 12/3/24
617/55. Anodic Electrocleaning vs electrolysis of rust - October 16
617/45. Problem aluminum phosphating mild steel - October 11
616/91. Zinc Phosphate - Coating Continuity Problem 2nd Request - September 23
530/95. What is the best frequency range (28-40 HZ) for ultrasonic wax & degrease removal? - September 17
617/28. Which chemicals for heat-treated Monel? - September 9
617/07. Effective Replacement of HCl as Pickling Bath - August 19
91/46. Chemical & Electropolishing of Brass: solutions, procedures, references - August 15
133/66. White Stain after Phosphating Die Castings - August 5
617/01. Precleaning steel wire before plastic coating at high speed
- August 1
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1c. Capping, plugging, masking, taping
617/47. Protective masking for stripping and re-anodizing - October 9
617/35. Masking my CZ Shadow for Plating - September 22
273/43. Masking for Nickel Plating
- September 2
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2. Metallic & inorganic finishes
2a. STAINLESS, TITANIUM, CORROSION-RESISTANT METALS PROCESSING
12/53. Electrical Properties of Passivated Stainless Steel - 1/6/25
460/41. Electropolishing 4xx / 400 series stainless steel - 12/31/24
309/65. Can't remove old plastic protection film from stainless steel - 12/27/24
85/05. How to smoothly etch stainless steel materials - 12/26/24
214/37. "Rainbowing" and "Bluing" method for Stainless Steel - 12/14/24
90/61. Passivating Laser Cut Stainless Steel Problem - 12/14/24
315/41. Electropolishing stainless steel to a 'satin' finish - 12/6/24
335/04. Anodizing Titanium for Wear Resistance & Anti-Galling - October 18
121/46. Refinishing scratched stainless appliances - October 14
26/29. Component burned all the way through from electropolishing - September 24
553/76. Pickling & Passivating 410S stainless steel per ASTM A380? - September 9
440/70. Durable black coatings for stainless steel
- August 28
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2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
339/33. Masking/stripping when chromate conversion and anodizing on same part - 1/20/25
617/75. Aluminum in the 1930's: "Deplated Finish" - 12/27/24
432/48. "Two-step" black anodizing w/tin sulphate: Q&A - 12/21/24
617/89. Removing calcium & zinc from rinse water on aluminum anodizing line Inquirer often helps others, so especially deserves our help - 12/20/24
617/87. Anodizing: missed one tapped hole; how to re-do? - 12/18/24
137/75. How to Chromate Conversion Coat ADC12 - 12/7/24
295/19. How to Mask for Hardcoat Anodize - 12/4/24
613/75. Chromate Conversion Coating as Paint/Powder Prep - 12/3/24
415/31. Ultrasonic cleaning of anodizing leaves white stain 2nd Rqst - 12/3/24
533/57. Slime/algae on surface of anodizing tank - 11/27/24
617/74. Anodizing: Small Area That Doesn't Dye - November 23
617/70. Simultaneous etch-passivation solution for aluminium pretreatment - November 18
144/62. Spot type seal check for black anodized aluminum - November 14
617/64. Skin products affecting dyed anodizing? - November 1
338/83. Problems in Plating on Aluminum (ADC-12) - October 30
617/62. Delay between Aluminum Chromate & Powder Coating - October 24
617/44. Black Anodize Blemishes & Spots - October 14
617/51. Problem dying anodized aluminum green - October 11
617/37. Is Discoloration an Etching Problem? - October 11
617/26. Black dust on dyed black anodized aluminium - September 28
279/90. Anodizing is Flaking Off of 7075 Aluminum Parts - September 28
617/00. Need titanium anodizer for multi-color sheets for kitchen cabinets RFQ: London UK - September 25
600/68. Aluminum sheet shows stripes after chromate conversion coating - September 23
617/36. Affect of water on 6061 anodized aluminum - September 21
617/41. Aluminum certified as the same etches differently - September 18
242/36. Epoxy primer not adhering to conversion coated aluminum (failing bend test) - September 9
515/73. Anodizing rectifier & chiller sizing - August 28
423/62. What were the two types in the old Mil-C-5541 spec? - August 27
617/16. Odd porosity on anodized threads AFTER sealing - August 26
434/84. Low Anodizing Thickness in Gap between Plates - August 26
615/29. Anodized Aluminium edges not taking dye very well - August 12
67/84. Need 0.5 Ra after Anodizing - August 6
400/35. Desmut can't remove black coloration from etching - August 5
616/99. Alloy wheels: is chrome plating or anodizing better?
- August 1
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2c. ELECTROPLATING and ELECTROFORMING
617/91. Gold Plating thickness variation - 12/28/24
429/81. Cost of Metal Plating - 12/22/24
559/01. Gold plating color change - tarnish problem - 12/21/24
617/84. Nickel & Chrome Plating Rusts in 8 Hours - 12/21/24
617/34. Cleaning Porous Pot Cathodes - There's gotta be a better way! Inquirer often helps others, so especially deserves our help - 12/20/24
617/81. Zinc plating & trivalent black chromate gives poor salt spray hours - 12/19/24
327/83. Replating chrome onto existing chrome - 12/18/24
490/09. Chrome Bath Help: Chrome to Acid Ratio - 12/14/24
126/37. Zinc plating on copper Q&A, Problems & Solutions - 12/12/24
158/09. Zinc plating with black Trivalent Chromate Fails Salt spray - 12/7/24
38/92. Ti-Cd: Bath concentration okay, but weight percentage of Ti in plating is low - 12/3/24
540/61. Copper Pyrophosphate Plating for DMM Recording Disks - 11/28/24
61647. Complete Process for Cleaning, Cu, and Ag Barrel Plating - 11/28/24
288/51. Zinc-nickel plating makes metal dust when crimping - 11/27/24
617/25. Hard chromium plating rate is way low Inquirer often helps others, so especially deserves our help - 11/27/24
617/68. Cyanide Copper & Stannate Tin Process Questions - 11/25/24
236/32. Tin Plating Problems: black spots - 11/25/24
323/63. Acid zinc plating Anodes Q&A - November 19
617/71. Cadmium Density vs. Plating Speed Inquirer often helps others, so especially deserves our help - November 15
617/61. Nickel-Cobalt Electroplating - October 31
617/03. Tri-chrome chloride bath stain - October 30
318/16. Electroplated gold turns red - October 30
617/49. Need parts plated to GM-6164M RFQ: Jackson, MI - October 15
144/61. Hard Chrome Plating Peels Off of Inconel - October 14
424/47. Egg Albumin Is Staining Nickel Electroforms - October 13
61752. Cyanide copper plating on zinc diecast - October 13
617/48. Purple Color on Filter of Gold Cyanide Plating Bath - October 9
61740. Can We Chrome Plate Super Duplex S32760 - October 9
616/86. Zinc Plating Peels Off Stainless Steel During Crimping Process - October 9
552/25. Alkaline zinc plating problem: Black dots/spots - October 8
128/79. Rack mark / jig mark problems in electroplating - October 8
340/23. Nickel-Chrome plating on Brass Problems - September 29
617/20. Hard Chrome VI plating throwing power problem Inquirer often helps others, so especially deserves our help - September 23
616/15. Zinc plating with blue passivation is yellowish at holes - September 23
616/03. Zinc Plating has white & red rust without a cause - September 23
133/56. Zinc Plating of 12L14 Leaded Steel - September 23
617/38. Acid Zinc Plating Bath White Appearance - September 21
591/81. Need Electroplating on 3D Printed Jewelry RFQ: San Diego, CA - September 17
617/29. Is This a Chrome Plating Defect? - September 17
122/43. Black Spots when Tin Plating Brass - September 9
617/22. Lead plating of umbrella wires/tubes - September 7
173/11. How to do copper plating on aluminum roller? - September 5
526/02. Grayish black spots over time in zinc plating - 8/28/24
617/17. Separating copper and nickel for optics - 8/28/24
617/13. Accidentally Put Dechrome in Chrome Plating Tank - 8/21/24
617/10. Fluoborate Copper plating process - 8/21/24
617/09. Plating blisters observed on tin finish after annealing - 8/21/24
617/02. Zinc-Nickel Plating -- Dark Deposit in LCD Area - 8/5/24
15/03. Platinum Plating: How to Determine Replenishment
- 8/3/24
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2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
168/97. Electroless nickel plating onto stainless steel - 12/12/24
584/27. "Water spots" on electroless nickel plated parts - 11/25/24
617/63. Electroless nickel plating: white marks - October 31
345/41. Electroless Nickel with PTFE Plating Problems - September 9
617/24. Silver mirroring puddles on glass, oxidizes at the edges - September 8
617/11. Need Cosmichrome in California RFQ: California - August 21
616/08. Electroless copper plating onto wax - August 1
536/23. Electroless Plating onto LCP Engineering Plastic
- August 1
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2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
617/90. Need to TiN coat a circular blade, 90 mm dia x 2 mm thick - 200 pcs RFQ: Murfreesboro, TN - 12/23/24
607/71. High Temperature PVD Coatings - 12/14/24
78/46. PVD coatings: color control Q&A's, Problems & Solutions - August 26
285/27. Vacuum Metallizing Gets Hazing as soon as Top Coated
- August 5
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2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
449/78. Galvanizing kettle furnace and burner design - 1/10/25
492/71. Galvanizing flux: Ammonium chloride requirements and analysis - 1/10/25
61798. Galvanizing: Product Quality Issue with Shipped Containers - 1/7/25
616/98. Planning a small HDG plant - 1/6/25
568/67. Spotting, Staining, Blackening of Hot Dip Galvanized Finish - 12/31/24
613/16. Hot-Dip Tinning Problems & Solutions: hard tin crystals - 12/6/24
617/43. Galvanizing Vats Overheated ... Need supplies, lab equipment, etc. RFQ: Angola - 10/13/24
617/41. Agitation of Galvanizing Flux Inquirer often helps others, so especially deserves our help - 9/28/24
453/09. White spots left by coolants on galvanized steel - 8/19/24
382/05. Galvanizing problem: Excessive aluminum in zinc
- 8/12/24
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2g. BLACK OXIDE, BLUING, COLORING, PATINAS
617/73. Black spots on chemically blackened brass - November 15
117/76. Standards for Oiling of Black Oxided Parts - October 15
362/14. Formula for cold blackening / cold black oxide - October 6
11/50. How to Get Clear Coat Look from Gun Bluing?
- August 3
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2h. OTHER INORGANIC FINISHING: Mechanical Plating, Nitriding & QPQ, Metal Spray, Zinc-rich Dip-Spin Coatings, Sherardizing, Rust Preventatives, etc.
286/21. Geomet 750 Hp galvanizing - August 6
553/66. Ferritic Nitrocarburizing has red color to it? - June 15
526/75. Process Comparison for Tufftriding and Nitriding - March 20
401/39. Rust spots on pickled coil after a few days - September 1
3. ORGANIC FINISHING [PAINT, POWDER COATING] . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
456/18. E-coating over Zinc or Zinc Alloy Plating - 1/10/25
617/82. E-coat throwing power, coverage inside tubes
- 12/11/24
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3b. POWDER COATING
524/55. Actual costing of powder coating in India - October 6
617/04. Powder Coating on Zinc Plating with White Rust
- August 20
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3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
226/74. Want anti-pit solvent for Electrophoretic Lacquer - 12/4/24
54/18. Clear Coating Black Oxided Stainless Steel?
- November 18
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3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
617/94. Putting plastisol on zinc plated parts - 12/29/24
617/30. Epoxy ink fisheyeing on TGIC-polyester powder coating
- September 10
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4. POST-TREATMENTS
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
372/55. Restoring the yellow dichromate finish on automobile carburetors - 1/19/25
385/77. Need Iridite 17p RFQ: California
- September 7
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4b. BAKING AND NON-CHEMICAL POST-TREATMENTS [HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]
4c. STRIPPING, REWORKS, ETC.
297/78. Stripping chrome plating Q&A, Problems & Solutions - 12/23/24
617/54. Zinc Phosphate stripping for coating weight - 11/25/24
114/99. Stripping TiN (Titanium Nitride) Coating from Titanium
- 10/31/24
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5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
617/97. Need Lab Help with Stainless Product Development - 1/7/25
442/93. On line analysis of chrome concentration? Inquirer often helps others, so especially deserves our help - 12/21/24
547/76. Caustic Etch Analysis -- aluminium anodizing - 12/18/24
328/38. Analyze Chrome Plating Bath; Determine sulphates - 12/9/24
45510. Analysis of potassium carbonate in cyanide plating bath - 12/3/24
329/52. Diphenylcarbohydrazide Trivalent/Hexavalent Chrome Testing - November 23
617/78. Need to create pitting corrosion on stainless steel - November 23
21/83. Can you reliably measure nitric acid concentration with specific gravity gauge?
- October 13
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5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
617/85. Spot test for cyanide in waste water - 12/15/24
617/46. Determining if WWT sludge is hazardous? - October 9
123/75. Remove Copper from Plating Waste - September 23
617/14. Sludge from ETP plant
- August 21
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5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
110/17. Safety of Drinking D.I. Water - 12/18/24
617/83. Safety of "Chrome" Vinyl Wrap - 12/15/24
208/58. Toxicity of nickel silver punch bowl - November 1
406/57. Inhaled fumes from Bleach and C.L.R. accidentally mixed - September 20
617/27. Popping Popcorn in Galvanized Buckets -- is it safe? - September 8
329/77. Diatomaceous Earth and Shellfish Allergies?
- August 21
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5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
617/93. Learn more about automatic electroplating production lines - 12/28/24
617/79. Ideas for heating an alkaline zinc bath? - 11/25/24
599/93. Exhaust method & calculations for plating tanks - November 18
391/55. Stripping plastisol from plating racks - November 12
617/57. Ideas for heating an alkaline zinc bath - October 21
114/65. Sludge buildup on heating coils in phosphating tank - October 10
123/73. Zinc oxide production by French process? - September 19
617/33. Heating Chrome tanks with Hot Water in Lieu of Steam - September 16
617/21. Titanium Grade for Aluminum Anodizing Jigs - September 7
435/15. Air Agitation of HCl Pickle Tank
- August 14
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5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, HISTORY, ETC.
618/00. Meaning of "Zinc electrolyte plating + leaching"? - 1/16/25
461/40. Boeing Chloride Limits for Nickel Sulfamate Plating Bath? - 12/3/24
342/14. MIL-DTL-5541 Adhesion tape testing with 3M #250 discontinued - November 23
617/69. ASTM B700, Type II, Grade D, Class N vs. Class J? - November 18
617/53. What is Phosphate Treatment 5.1.3.3 from spec 1.9.3? - October 30
617/58. Did Wahl Clippers Have Cadmium Plating in the 1970s? - October 21
616/32. Does MIL-C-5541 forbid a "Do Not Etch" instruction? - September 17
423/62. MIL-C-5541 Chemical Conversion Coat -- Legacy Q&A's
- August 26
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5f. W...W...W...WORD OF THE WEEK
5g. MOSTLY METALLURGY; Heat Treatment
617/77. 3d printed Inconel 718 part turns blue in vacuum heat treatment
- November 16
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5h. METAL RECOVERY
418/91. Recover gold from gold plated stainless steel wire - 1/14/25
50/48. Extracting Gold from Computer Circuit Boards? - 1/5/25
319/63. Remove tin plating from copper pots, trays, cookware, etc. - 12/15/24
336/16. Gold Recovery for Dummies - September 28
278/14. How to Recover Platinum from Catalytic Converters
- August 2
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6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
565/54. Acid Zinc Plating Brightener Q&A - 1/18/25
268/45. Chip on Gloss Black Gas Stovetop - 1/15/25
02/83. Finishing of Kenrick 19th century cast iron - 1/14/25
611/46. Dumbbells have white corrosion on them - 1/14/25
617/99. Hobbyist Copper Plating on 3D Plastics: Help Fine-Tuning It - 1/8/25
617/96. Electroplating bath plates Nickel or Copper depending on voltage - 12/30/24
617/95. Need food-safe pliers - 12/30/24
12/15. Lead-free Antiquing Wears Right Off - 12/28/24
209/88. Restore silver damaged by peroxide - 12/28/24
309/65. Can't remove old plastic protection film from stainless steel - 12/27/24
344/65. Pre-coating for sublimation transfers onto ceramic - 12/27/24
611/11. Brass Threshold Turned Silver from Polishing - 12/12/24
236/53. Model railroading: Effect of oxidation of nickel silver on its conductivity - 12/6/24
617/80. Preparing Part for Replating with Chrome - 11/27/24
339/56. How to darken aluminum. Want golden yellow look on aluminum - November 16
202/40. Penny isn't copper color - what do I have? - October 29
185/19. Cleaning & polishing gold plated flatware - October 24
617/56. Anodizing aluminum: dye is splotchy - October 21
289/63. What could be causing the pitting and corroding to chrome fixtures - October 8
26/62. Preserving heat coloring of copper when clear coating - October 6
443/80. Nickel plating, how much SLS for wetting agent? - October 6
301/86. Lime-Away Damaged Stainless Steel Sink - September 19
331/43. Stiffel Lamps: need screws that hold laurel leaves - September 10
229/03. Ospho prep left tacky film - September 8
617/18. Barbell discolored in storage - September 2
191/05. Found a silver penny - August 29
163/04. Need 29 Emtek Brass Door Knobs Refinished RFQ: Texas - August 28
386/28. Gold plating of lead - August 28
128/41. Arcing, Popping & Hydrogen "Explosions" in Plating - August 27
381/37. How to Paint Bathtub Jets - August 19
372/05. Sterling silver vs. silver plate -- How to tell? - August 11
106/64. Touching up powder coated aluminum outdoor furniture (Tropitone) - August 10
559/51. Home nickel plating with vinegar and salt - August 1
85/75. Remove Water Stain from Teak - August 1
601/91. Restoring black exterior door hardware - August 3
166/99. Want Geneva Metal Kitchen Cabinets RFQ: New York
- August 2
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6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
00/98. Electroplating (Electrodeposition) of Niobium - 12/26/24
617/86. Adding Fe/Cu to Hard Chrome Plating Bath as DOE? - 12/15/24
617/39. Electroplating V, Zr and Ti - September 28
617/19. Electroplating: Role of a chemist - September 10
288/89. Measuring the pH of air - August 24
617/12. Galvanic Issues with Nickel-Plated Aluminum vs. Stainless?
- August 21
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6c. K-12 Science Projects, Grammar & High School Student Questions
6d. The Artists' Corner
65/07. Benzotriazole and substitutes for brass corrosion control - November 16
617/50. Forcing a white patina on zinc for watch dials - October 11
240/61. Finish for Bare Steel -- linseed oil?
- August 10
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7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
190/39. Need Legs for Martin Wood Stove - 1/15/25
293/70. "Art Deco" cocktail Ring - 12/28/24
128/73a. Removing Silica Water Stains - 12/27/24
258/52. Fixing scratched glass - 12/18/24
238/97. How to identify old brass, copper, bronze, cast iron lamps? - 12/7/24
324/13. Need sweet spirits of nitre (the traditional folk medicine) - 12/4/24
190/39. Need Door for Kalamazoo Stove RFQ: New Jersey, USA - 12/3/24
143/42. Is it a Stiffel? - 11/28/24
128/73a. Removing Silica Water Stains - November 23
304/79. Copper corrosion and blue water in residential water system - November 18
441/90. Problem related to cyanide addition - November 13
617/65. Is Spirits of Nitre or Paregoric good for your nerves? - October 31
268/01. Solving an electrolysis problem in home plumbing - October 25
22/59. High Temperature Adhesive for Mica to Silicone Rubber - September 23
238/97. Identify this unique lamp - August 18
617/06. Kitchen Floor Stained by Glue Trap
- August 18
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