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 1989-2024
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0. Choosing a finish, corrosion
354/05. Copper/Aluminum interaction and galvanic/hydrolysis problems - 12/12/24
617/67. Looking for the hardest, unscratchable finish for jewelry RFQ: Idaho - 12/4/24
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"
61723. Mirror polishing very small hardened steel components - September 25
61715. Shot blasting for acidic electroplating - August 21
61708. Spots on steel parts from tumbling
- August 19
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1b. CHEM PREP topics: "Cleaning, pickling, etching, phosphatizing, activation"
0960. Can phosphate coating be blackened with black chromate - 12/14/24
61776. Mixed metal pretreatment configuration - 12/9/24
1404. Electropolishing of silver - 12/3/24
61755. Anodic Electrocleaning vs electrolysis of rust - October 16
61745. Problem aluminum phosphating mild steel - October 11
61691. Zinc Phosphate - Coating Continuity Problem 2nd Request - September 23
53095. What is the best frequency range (28-40 HZ) for ultrasonic wax & degrease removal? - September 17
61728. Which chemicals for heat-treated Monel? - September 9
61707. Effective Replacement of HCl as Pickling Bath - August 19
9146. Chemical & Electropolishing of Brass: solutions, procedures, references - August 15
133/66. White Stain after Phosphating Die Castings - August 5
61701. Precleaning steel wire before plastic coating at high speed
- August 1
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1c. Capping, plugging, masking, taping
61747. Protective masking for stripping and re-anodizing - October 9
61735. Masking my CZ Shadow for Plating - September 22
27343. Masking for Nickel Plating
- September 2
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2. Metallic & inorganic finishes
2a. STAINLESS, TITANIUM, CORROSION-RESISTANT METALS PROCESSING
21437. "Rainbowing" and "Bluing" method for Stainless Steel - 12/14/24
9061. Passivating Laser Cut Stainless Steel Problem - 12/14/24
31541. Electropolishing stainless steel to a 'satin' finish - 12/6/24
33504. Anodizing Titanium for Wear Resistance & Anti-Galling - October 18
12146. Refinishing scratched stainless appliances - October 14
2629. Component burned all the way through from electropolishing - September 24
55376. Pickling & Passivating 410S stainless steel per ASTM A380? - September 9
44070. Durable black coatings for stainless steel - August 28
44070. Durable black coatings for stainless steel
- August 19
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2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
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
13775. How to Chromate Conversion Coat ADC12 - 12/7/24
29519. How to Mask for Hardcoat Anodize - 12/4/24
613/75. Chromate Conversion Coating as Paint/Powder Prep - 12/3/24
41531. Ultrasonic cleaning of anodizing leaves white stain 2nd Rqst - 12/3/24
53357. Slime/algae on surface of anodizing tank - 11/27/24
61775. Aluminum in the 1930's: "Deplated Finish" - 11/26/24
61774. Anodizing: Small Area That Doesn't Dye - November 23
61770. Simultaneous etch-passivation solution for aluminium pretreatment - November 18
14462. Spot type seal check for black anodized aluminum - November 14
61764. Skin products affecting dyed anodizing? - November 1
33883. Problems in Plating on Aluminum (ADC-12) - October 30
61762. Delay between Aluminum Chromate & Powder Coating - October 24
61744. Black Anodize Blemishes & Spots - October 14
61751. Problem dying anodized aluminum green - October 11
61737. Is Discoloration an Etching Problem? - October 11
61726. Black dust on dyed black anodized aluminium - September 28
27990. Anodizing is Flaking Off of 7075 Aluminum Parts - September 28
61700. Need titanium anodizer for multi-color sheets for kitchen cabinets RFQ: London UK - September 25
60068. Aluminum sheet shows stripes after chromate conversion coating - September 23
61736. Affect of water on 6061 anodized aluminum - September 21
617/41. Aluminum certified as the same etches differently - September 18
24236. Epoxy primer not adhering to conversion coated aluminum (failing bend test) - September 9
51573. Anodizing rectifier & chiller sizing - August 28
42362. What were the two types in the old Mil-C-5541 spec? - August 27
61716. Odd porosity on anodized threads AFTER sealing - August 26
43484. Low Anodizing Thickness in Gap between Plates - August 26
61529. Anodized Aluminium edges not taking dye very well - August 12
6784. Need 0.5 Ra after Anodizing - August 6
40035. Desmut can't remove black coloration from etching - August 5
61699. Alloy wheels: is chrome plating or anodizing better?
- August 1
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2c. ELECTROPLATING and ELECTROFORMING
559/01. Gold plating color change - tarnish problem - 12/21/24
61784. Nickel & Chrome Plating Rusts in 8 Hours - 12/21/24
61734. Cleaning Porous Pot Cathodes - There's gotta be a better way! Inquirer often helps others, so especially deserves our help - 12/20/24
61781. Zinc plating & trivalent black chromate gives poor salt spray hours - 12/19/24
32783. Replating chrome onto existing chrome - 12/18/24
49009. Chrome Bath Help: Chrome to Acid Ratio - 12/14/24
12637. Zinc plating on copper Q&A, Problems & Solutions - 12/12/24
15809. Zinc plating with black Trivalent Chromate Fails Salt spray - 12/7/24
3892. Ti-Cd: Bath concentration okay, but weight percentage of Ti in plating is low - 12/3/24
54061. Copper Pyrophosphate Plating for DMM Recording Disks - 11/28/24
61647. Complete Process for Cleaning, Cu, and Ag Barrel Plating - 11/28/24
28851. Zinc-nickel plating makes metal dust when crimping - 11/27/24
61725. Hard chromium plating rate is way low Inquirer often helps others, so especially deserves our help - 11/27/24
61768. Cyanide Copper & Stannate Tin Process Questions - 11/25/24
23632. Tin Plating Problems: black spots - 11/25/24
323/63. Acid zinc plating Anodes Q&A - November 19
61771. Cadmium Density vs. Plating Speed Inquirer often helps others, so especially deserves our help - November 15
61761. Nickel-Cobalt Electroplating - October 31
61703. Tri-chrome chloride bath stain - October 30
31816. Electroplated gold turns red - October 30
61749. Need parts plated to GM-6164M RFQ: Jackson, MI - October 15
14461. Hard Chrome Plating Peels Off of Inconel - October 14
42447. Egg Albumin Is Staining Nickel Electroforms - October 13
61752. Cyanide copper plating on zinc diecast - October 13
61748. Purple Color on Filter of Gold Cyanide Plating Bath - October 9
61740. Can We Chrome Plate Super Duplex S32760 - October 9
61686. Zinc Plating Peels Off Stainless Steel During Crimping Process - October 9
55225. Alkaline zinc plating problem: Black dots/spots - October 8
12879. Rack mark / jig mark problems in electroplating - October 8
34023. Nickel-Chrome plating on Brass Problems - September 29
61720. Hard Chrome VI plating throwing power problem Inquirer often helps others, so especially deserves our help - September 23
61615. Zinc plating with blue passivation is yellowish at holes - September 23
61603. Zinc Plating has white & red rust without a cause - September 23
13356. Zinc Plating of 12L14 Leaded Steel - September 23
61738. Acid Zinc Plating Bath White Appearance - September 21
59181. Need Electroplating on 3D Printed Jewelry RFQ: San Diego, CA - September 17
61729. Is This a Chrome Plating Defect? - September 17
12243. Black Spots when Tin Plating Brass - September 9
61722. Lead plating of umbrella wires/tubes - September 7
17311. How to do copper plating on aluminum roller? - September 5
52602. Grayish black spots over time in zinc plating - 8/28/24
61717. Separating copper and nickel for optics - 8/28/24
61713. Accidentally Put Dechrome in Chrome Plating Tank - 8/21/24
61710. Fluoborate Copper plating process - 8/21/24
61709. Plating blisters observed on tin finish after annealing - 8/21/24
61702. Zinc-Nickel Plating -- Dark Deposit in LCD Area - 8/5/24
1503. 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
16897. Electroless nickel plating onto stainless steel - 12/12/24
584/27. "Water spots" on electroless nickel plated parts - 11/25/24
61763. Electroless nickel plating: white marks - October 31
34541. Electroless Nickel with PTFE Plating Problems - September 9
61724. Silver mirroring puddles on glass, oxidizes at the edges - September 8
61711. Need Cosmichrome in California RFQ: California - August 21
61608. Electroless copper plating onto wax - August 1
53623. 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 - 12/21/24
60771. High Temperature PVD Coatings - 12/14/24
7846. PVD coatings: color control Q&A's, Problems & Solutions - August 26
28527. Vacuum Metallizing Gets Hazing as soon as Top Coated
- August 5
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2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
568/67. Spotting, Staining, Blackening of Hot Dip Galvanized Finish - 12/21/24
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
616/98. Planning a small HDG plant - 8/16/24
382/05. Galvanizing problem: Excessive aluminum in zinc
- 8/12/24
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2g. BLACK OXIDE, BLUING, COLORING, PATINAS
61773. Black spots on chemically blackened brass - November 15
11776. Standards for Oiling of Black Oxided Parts - October 15
36214. Formula for cold blackening / cold black oxide - October 6
1150. 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.
28621. Geomet 750 Hp galvanizing - August 6
55366. Ferritic Nitrocarburizing has red color to it? - June 15
52675. Process Comparison for Tufftriding and Nitriding - March 20
40139. Rust spots on pickled coil after a few days - September 1
3. ORGANIC FINISHING [PAINT, POWDER COATING] . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
3b. POWDER COATING
52455. Actual costing of powder coating in India - October 6
61704. Powder Coating on Zinc Plating with White Rust
- August 20
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3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
22674. Want anti-pit solvent for Electrophoretic Lacquer - 12/4/24
5418. Clear Coating Black Oxided Stainless Steel?
- November 18
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3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
61730. 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]
38577. 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.
61754. Zinc Phosphate stripping for coating weight - 11/25/24
11499. 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
44293. On line analysis of chrome concentration? Inquirer often helps others, so especially deserves our help - 12/21/24
54776. Caustic Etch Analysis -- aluminium anodizing - 12/18/24
32838. Analyze Chrome Plating Bath; Determine sulphates - 12/9/24
45510. Analysis of potassium carbonate in cyanide plating bath - 12/3/24
32952. Diphenylcarbohydrazide Trivalent/Hexavalent Chrome Testing - November 23
61778. Need to create pitting corrosion on stainless steel - November 23
2183. Can you reliably measure nitric acid concentration with specific gravity gauge?
- October 13
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5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
61785. Spot test for cyanide in waste water - 12/15/24
61746. Determining if WWT sludge is hazardous? - October 9
12375. Remove Copper from Plating Waste - September 23
61714. Sludge from ETP plant
- August 21
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5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
11017. Safety of Drinking D.I. Water - 12/18/24
61783. Safety of "Chrome" Vinyl Wrap - 12/15/24
20858. Toxicity of nickel silver punch bowl - November 1
40657. Inhaled fumes from Bleach and C.L.R. accidentally mixed - September 20
61727. Popping Popcorn in Galvanized Buckets -- is it safe? - September 8
32977. Diatomaceous Earth and Shellfish Allergies?
- August 21
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5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
61779. Ideas for heating an alkaline zinc bath? - 11/25/24
59993. Exhaust method & calculations for plating tanks - November 18
39155. Stripping plastisol from plating racks - November 12
61757. Ideas for heating an alkaline zinc bath - October 21
11465. 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
61721. Titanium Grade for Aluminum Anodizing Jigs - September 7
43515. Air Agitation of HCl Pickle Tank
- August 14
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5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, HISTORY, ETC.
46140. Boeing Chloride Limits for Nickel Sulfamate Plating Bath? - 12/3/24
34214. MIL-DTL-5541 Adhesion tape testing with 3M #250 discontinued - November 23
61769. ASTM B700, Type II, Grade D, Class N vs. Class J? - November 18
61753. What is Phosphate Treatment 5.1.3.3 from spec 1.9.3? - October 30
61758. Did Wahl Clippers Have Cadmium Plating in the 1970s? - October 21
61632. Does MIL-C-5541 forbid a "Do Not Etch" instruction? - September 17
42362. 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
61777. 3d printed Inconel 718 part turns blue in vacuum heat treatment
- November 16
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5h. METAL RECOVERY
319/63. Remove tin plating from copper pots, trays, cookware, etc. - 12/15/24
33616. Gold Recovery for Dummies - September 28
27814. How to Recover Platinum from Catalytic Converters
- August 2
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6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
61111. Brass Threshold Turned Silver from Polishing - 12/12/24
23653. Model railroading: Effect of oxidation of nickel silver on its conductivity - 12/6/24
61780. Preparing Part for Replating with Chrome - 11/27/24
33956. How to darken aluminum. Want golden yellow look on aluminum - November 16
20240. Penny isn't copper color - what do I have? - October 29
18519. Cleaning & polishing gold plated flatware - October 24
61756. Anodizing aluminum: dye is splotchy - October 21
28963. What could be causing the pitting and corroding to chrome fixtures - October 8
2662. Preserving heat coloring of copper when clear coating - October 6
44380. Nickel plating, how much SLS for wetting agent? - October 6
30186. Lime-Away Damaged Stainless Steel Sink - September 19
33143. Stiffel Lamps: need screws that hold laurel leaves - September 10
22903. Ospho prep left tacky film - September 8
61718. Barbell discolored in storage - September 2
19105. Found a silver penny - August 29
16304. Need 29 Emtek Brass Door Knobs Refinished RFQ: Texas - August 28
38628. Gold plating of lead - August 28
12841. Arcing, Popping & Hydrogen "Explosions" in Plating - August 27
38137. How to Paint Bathtub Jets - August 19
37205. Sterling silver vs. silver plate -- How to tell? - August 11
10664. Touching up powder coated aluminum outdoor furniture (Tropitone) - August 10
55951. Home nickel plating with vinegar and salt - August 1
8575. Remove Water Stain from Teak - August 1
60191. Restoring black exterior door hardware - August 3
16699. Want Geneva Metal Kitchen Cabinets RFQ: New York
- August 2
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6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
61786. Adding Fe/Cu to Hard Chrome Plating Bath as DOE? - 12/15/24
61739. Electroplating V, Zr and Ti - September 28
61719. Electroplating: Role of a chemist - September 10
28889. Measuring the pH of air - August 24
61712. 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
6507. Benzotriazole and substitutes for brass corrosion control - November 16
61750. Forcing a white patina on zinc for watch dials - October 11
24061. Finish for Bare Steel -- linseed oil?
- August 10
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7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
25852. Fixing scratched glass - 12/18/24
29370. Marking system for rings, Hallmarks - 12/15/24
23897. How to identify old brass, copper, bronze, cast iron lamps? - 12/7/24
32413. Need sweet spirits of nitre (the traditional folk medicine) - 12/4/24
19039. Replacement for Asbestos in Wood Cook Stove - 12/3/24
19039. Need Door for Kalamazoo Stove RFQ: New Jersey, USA - 12/3/24
14342. Is it a Stiffel? - 11/28/24
12873a. Removing Silica Water Stains - November 23
30479. Copper corrosion and blue water in residential water system - November 18
44190. Problem related to cyanide addition - November 13
61765. Is Spirits of Nitre or Paregoric good for your nerves? - October 31
26801. Solving an electrolysis problem in home plumbing - October 25
2259. High Temperature Adhesive for Mica to Silicone Rubber - September 23
23897. Identify this unique lamp - August 18
61706. Kitchen Floor Stained by Glue Trap
- August 18
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