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0. Corrosion. Compatibility, Choosing a Finish
Preparation:	1a. Mechanical Prep	1b. Pretreatments	1c. Masking & Racking
Inorganic Finishing:	2a. Anodizing & Light Metals	2b. Electroplating & Electroforming	2c. Electroless Plating	2d. PVD, CVD, Vacuum Processes
Inorganic Finishing:	2e. Galvanizing, Hot Dipping	2f. Black Oxide, Bluing, Coloring	2g. Other Inorganic Finishing Processes
Organic Finishing:	3a. Electropainting, Autophoretic	3b. Powder Coating	3c. Lacquers, Clearcoats	3d. Painting, Adhesives And Other Organic Coatings
Post-treatments:	4a. Chemical Post-treatments	4b. Baking & Non-chemical Post-treatments	4c. Stripping, Reworks, etc.
Supporting Issues:	5a. Analysis, Lab Technique, QA/QC	5b. Wastewater, Pollution	5c. Safety, Emissions, Toxicity	5d. Plant & Process Engineering
Supporting Issues:	5e. Software, Specs, Books, Stats	5f. World Wide Word Of The Week	5g. RoHS, E-O-L, etc.	5h. Mostly metallurgy
6a. Hobbyists, Enthusiasts, Artists		6b. Research, Thesis work	6c. K-12 Science Projects, Elementary to High School

4. POST-TREATMENTS

4a. CHEMICAL POST-TREATMENTS
[CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES]

49890. Best solution to clean Alkaline-Tin Plated Parts [South Dakota] (September 5)
49797. Difficulty detarnishing lead-based pewter [Indiana] (September 5)
49844. Chemical polishing / bright dipping of copper [Egypt] (September 2)
49777. Black Copper Oxide selective solar surface on steel, any methods? [Colombia] (August 26)
49743. Cleaning carbon brushes [India] (August 22)
49589. Protective coating for external copper cladding [India] (August 11)
48794. Coloring 18-8 stainless steel red [New Jersey] (August 11)
49600. Non toxic liquid anti-tarnish for jewelry [Philippines] (August 8)
49588. Copper desmut solution causes etching [Indonesia] (August 7)

4b. BAKING AND NON-CHEMICAL POST-TREATMENTS:
[HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]

49843. Soldering of galvanized iron wire [India] (September 2)
49433. Tarnish Prevention in low karat metals [New York] (August 15)
49487. Wetting and dewetting issues of C-Pins [Singapore] (July 31)

4c. STRIPPING, REWORKS, ETC.

49899. Home made chrome stripper/chrome activator [Cyprus] (September 8)
49889. Stripping nickel from brass [Turkey] (September 5)
49309. Stripping hard chromium from AISI 410 [Italy] (July 18)
49277. Replating of Brass Parts once plated with Tin; Can I replate with Nickel and Tin? [India] (July 10)

5. SUPPORTING ISSUES

5a. ANALYSIS, LAB TECHNIQUE, Q.A.

49898. Is this titration procedure correct? [Montana] (September 8)
49742. Hardness test [Kentucky] (August 30)
49450. Analysing why sodium cyanide solution is contaminated [Philippines] (August 20)
49644. UV/Vis Spectrophotometry methods [New York] (August 14)
49338. Determination of acidity in pickling and phosphatizing [Colombia] (August 11)
49095. I wish to know how to test free acidity of the bath [India] (August 11)
49219. How to check amount of metal in copper and silver plating baths? [Mississippi] (August 11)
49558. Coating thickness is wearing away when heated after coating nickel on copper [India] (August 7)
49449. Testing for correct concentrations in immersion coppering bath [India] (July 28)

5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL

49897. Temperature increase in cyanide treatment [Spain] (September 8)
49888. Regeneration of Cation Exchanger [India] (September 5)
49829. Gold recovery from old "jewelry bombing" solution [Florida] (September 3)
49809. Feed water for DM plant [India] (August 30)
49757. Waste classification/volume reduction of stripped paint waste solids [New York] (August 22)
49657. How to dry paint overspray collected in a water bath? [Canada] (August 15)
49656. pH of Deionized Water as related to Fusion Bonded Epoxy Coating [Texas] (August 14)
49307. Hydrofluoric acid disposal for small lab [California] (August 7)
49512. Reuse/recycle of rhodium plating solution [India] (August 1)

5c. SAFETY ISSUES, EMISSIONS, TOXICITY

49673. Plating Tank Disposal [Minnesota] (September 2)
49448. Cement finisher for 30 years why the blisters on the back of my hands [Washington] (August 29)
49633. Determining appropriate PPE for an anodizing line [Idaho] (August 28)
49632. Is it hazardous to sand chrome? [Oregon] (August 13)
49587. Copper sulfate's long-term effect on human brain [Michigan] (August 8)
49511. Toxicity of Chromium in stainless steel - Hexavalent vs Trivalent [Australia] (August 1)

5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION

49887. HCI tank mating flange gasket material? [Malaysia] (September 5)
49842. Workshop floor is slippery [UK] (September 4)
49859. Physical Properties of Cadmium Plating Solutions [Pennsylvania] (September 3)
49756. Need blue prints for Hanson-Van Winkle-Munning [Tennessee] (August 28)
49576. Reel to reel electroplating dummy [Singapore] (August 26)
49689. How can someone separate mill scale from a retention pond. [North Carolina] (August 18)

5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, INDUSTRY STATISTICS, ETC.

49886. Are there standards available outlining EDGE Card PCB thickness requirements? [Washington] (September 5)
49755. SAE AMS QQ-A-416 [New Jersey] (August 22)
49655. ASTM A380 copper sulfate MSDS [Minnesota] (August 15)
49510. NIDI 9012 - Finishes for Stainless Steel [Malaysia] (August 1)
49493. Is there a Mil-spec limit on surface area that can be brush plated? [The Netherlands] (August 1)
49422. A layman's explanation for the difference in NUC AP and NADCAP? [Georgia] (July 25)

5f. WORLD WIDE WORD OF THE WEEK
[LINGO, TRADE NAMES, TRANSLATIONS]

49796. What is Omega Plating [Israel] (August 29)
49715. In search of Root Coating Process [India] (August 26)
49616. In wood finishing: is "pickled" the same as "decapé"? [Italy] (August 12)
49531. MIL-F-14072 M228 [Pennsylvania] (August 11)

5g. CHROMATE REPLACEMENT & THE EUROPEAN END-OF-LIFE DIRECTIVE; Cd, Ni, Pb, Cr REPLACEMENTS.

49896. Can we comply with ROHS without doing trivalent plating [India] (September 8)
49858. Alternative process to chemical conversion coating [Turkey] (September 3)
49701. Are we meeting RoHS norm with hexavalent chromating? [India] (August 22)
49672. Testing for Clear Trivalent Chromate [Minnesota] (August 15)
49582. Analysis of Hexavalent versus Trivalent Chromate on Zinc Plating [Iowa] (August 7)
49475. I want to retain RoHS complaint from brass with nickel plated parts [India] (July 30)

5h. MOSTLY METALLURGY

49432. Cutlery mfgr wants better stainless to avoid rusting [Turkey] (July 30)
49243. Aluminium baffle damage [UK] (July 9)
49170. Stress relieving thin stainless steel deep drawn components [India] (July 1)

6a. ARTISTS, HOBBYISTS, CAR BUFFS, HOME OWNERS, ETC.

49895. Removed chrome from aluminum wheels, how to fill severe pitting? [Massachusetts]

(September 5)
49894. Ratio of sulphuric acid to water for anodizing [Montana]

(September 5)
49885. Wood window frame is embedded in stucco. How can we prevent rot? [Canada]

(September 5)
49884. Lightening oil-rubbed bronze finish [Washington] (September 5)
49883. Chlorine turned my wedding ring from gold to copper looking [Florida] (September 5)
49882. A product to paint the aluminum sides of my above ground pool which is starting to pit [Michigan]

(September 5)
49881. Sandblasting aluminum rims [Texas]

(September 5)
49880. Aluminum horse trailer corrosion protection [Texas]

(September 5)
49879. Sensitivity to Rhodium plated Jewelry [Texas] (September 5)
49857. Problems relacquering an alto sax [Connecticut] (September 5)
49856. Durable jewelry finishes [Michigan]

(September 5)
49855. Details on my ring seem to have been lost in re rhodium plating [Tennessee] (September 5)
49696. Rolled Steel Countertop has become a mess [Arizona]

(September 5)
49865. How to do gold plating [Mauritius] (September 4)
49854. Brush plating solutions [Croatia]

(September 3)
49841. Need clips for wire shelves in Geneva Cabinets [Massachusetts]

(September 2)
49840. Equipment needed for sink and elevator resurfacing business? [Colorado]

(September 2)
49839. Can a fireplace insert be used as a stand alone wood stove? [Massachusetts] (September 2)
49828. Chrome plating over a stainless steel, Springer front end [New Zealand] (September 2)
49794. Removing firecoat after silver soldering [California] (September 2)
49779. What is the base metal for silver plated trays? [South Carolina] (September 2)
49766. How difficult is it to plate a piece of jewelry with rhodium [Illinois] (September 2)
49827. Pitted Bathtub Chrome [Arizona] (August 30)
49788. Can a cracked clearcoat be abrasively removed with minimal damage to the base coat? [Georgia] (August 30)
49631. Can't remove tarnish from old brass lamp in this lifetime [France] (August 29)
49808. Electroforming Classes for Artists? [Tennessee]

(August 29)
49795. Polishing painted aluminum [Canada] (August 29)
49793. Sulphuric acid stains on an aluminum kitchen sink [Canada] (August 29)
49778. Need help with separating my gold, platinum and copper dust [Canada] (August 28)
49787. Thin rust like streaks on Kitchen Aid Stainless Refrigerator [California]

(August 28)
49752. Strange corrosion of copper by vinegar/salt/ammonia [Texas] (August 27)
49780. Want to put nickel plated wheels on 1938 Buick [Massachusetts]

(August 27)
49754. Muriatic acid treatment okay with Kids in the house? [Wisconsin] (August 22)
49753. Coloring aluminum for metalcast art [Texas] (August 22)
49741. Digital camera with battery corrosion [Michigan] (August 22)
49740. Seeking to repaint gold jewelry [California] (August 22)
49739. How to chemically remove weld seam marks from stainless steel? [Portugal] (August 22)
49738. Improving quality in gold plating and better way to do 1 gm [India] (August 22)
49737. Corrosion resistance of hard chrome vs. QPQ [Minnesota] (August 22)
49700. Gold wrinkle paint on glass for spool cabinet restoration [Florida]

(August 21)
49698. Recovering Gold from Mercury [Texas] (August 21)
49729. Can I Tungsten Carbide plate a white gold ring? [California] (August 21)
49697. Corrosion of stainless steel piping and utensils in new house [India] (August 20)
49366. How do I deplate silver off old broken silverware? [New York] (August 20)
49598. Simple help on setting up copper electrolysis [Alabama] (August 19)
49699. Help with original zinc die cast finish (how to restore) [The Netherlands] (August 19)
49670. In need of colored metal with coloring blended into the metal [California] (August 18)
49625. How to rhodium plate and not get steely grey [India] (August 18)
49681. Restore a Peoria Oak 1900s stove body [California] (August 15)
49653. How to protect an outdoor carbon steel forge from corrosion? [Virginia] (August 15)
49651. D-I-Y alternative to electroplating for motorcycle engine? [New Jersey] (August 15)
49629. Need to braze aluminum boat hull, but can't get it to tin [California] (August 15)
49671. How thick is layer of gold on plated craft wire? [Romania] (August 15)
49556. Preserving cement statue of Snow White and the 7 Dwarfs [Pennsylvania] (August 14)
49551. What paint type should I use to paint my car? [Canada] (August 14)
49549. Never do cleaning if you have Rhodium Jewelry! [Canada] (August 14)
49527. FDA approved finish for cement serving dishes? [Indiana] (August 14)
49505. What is the black coating on steel? [New York] (August 14)
49504. Restoring old wood burning inbuilt stove [Australia] (August 14)
49654. Reverse electroplating using salt water [Minnesota] (August 14)
49652. Any way to darken the finish of sealed wood cabinets other than stripping? [Texas]

(August 14)
49650. Bending Aluminium 6060T5 extrusion [Australia]

(August 14)
49643. Primer needed for aluminum gutters? [Georgia] (August 13)
49630. Want to do minor repair to Powder Coated railings [New Jersey] (August 13)
49628. Is odd looking black stuff sprayed on inside of tanker desk asbestos? [Canada]

(August 13)
49627. Aluminum wheel polishing help [New York]

(August 13)
49626. Found a buried ring, marked 14K but brown in color [Louisiana]

(August 13)
49470. How to prep aluminum or stainless classic auto trim parts for chrome plating? [Missouri] (August 12)
48729. My GM dealer says the peeling chrome wheels on my G6 are MY FAULT!!!

[West Virginia] (August 12)
49615. Black chrome radiator hoses [Michigan] (August 12)
49614. Translucent black paint for tail lights? [New York]

(August 12)
49613. How to durably finish teak for a floor [Pennsylvania] (August 12)
49612. Weatherizing new copper to match existing panels [Connecticut] (August 12)
49611. Why does topcoating of chrome-like paint causes yellowing? [Indonesia]

(August 11)
49580. Shoe bronzing question [France] (August 11)
49573. Preserving copper bartop of busy gulf pub [Florida] (August 11)
49509. Recovery of Gold from Potassium Gold Cyanide [Georgia] (August 11)
49599. Best Chemical Solution for brush coating [Canada] (August 8)
49581. Can't unscrew chromalloy bike peddles from aluminum crank arm [Michigan] (August 8)
49586. How can a shiny satin nickel plating be dulled? [Virginia]

(August 7)
49555. How do you stamp the weight into an ingot of silver or gold [North Carolina] (August 7)
49574. How to avoid yellowing of chemically deposited silver when I apply transparent topcoat? [Mexico]

(August 6)
49557. Candle wax stains on Granite Headstone [Pennsylvania] (August 6)
49554. Shower enclosure restoration options [Michigan] (August 6)
49553. Want to change exterior brass hardware to pewter color [Texas] (August 6)
49552. Protecting gold plated tapware [Australia]

(August 5)
49550. I want to purify my 80% gold ingot [Yemen]

(August 5)
49488. Plating a spiral staircase for Better Homes & Gardens contest winner [Florida] (August 5)
49482. Plating linkages 'as assemblies'? [South Africa]

(August 5)
49469. Problems activating Electroless Nickel plated parts [Scotland] (August 5)
48860. Protective coating for aluminum exposed to high pressure oxygen [New York] (August 5)
49508. What nails should I use for an outdoor railing cap? [New York] (August 4)
49506. How to paint Fiberglass Steps? [Maine] (August 4)
49503. Barrel wear from lead filled full metal steel jacket bullets. [Nevada] (August 4)
49530. Artist needs powder coated finish attracted by a magnet [California] (August 4)
49464. Cleaning up cement dust from sanding of concrete floor [Canada] (August 1)
49507. Electric Polishing of Brass [Australia] (August 1)
49474. Rust protection for antique iron fixture [Maryland] (July 31)
49472. Want a dark stainless steel finish for anchor chafing plate [California] (July 31)
49471. What type grade of stainless steel plates and size for a hydrogen engine project? [Wisconsin] (July 31)
49468. Cleaning service needs help removing fingerprints from mirror finished plastic reflectors [California] (July 31)
49089. Copper Electro-refining: All I get is copper powder/no adhesion to cathode [Indiana]

(July 31)
29955. Trying to restore copper ornamental dome on historical building [Wisconsin] (July 30)
49473. Chemistry math for cleaning die cast zinc parts [Texas] (July 30)
49431. Reverse electroplating silver is it possible? [West Virginia] (July 29)
49420. Bending of body jewelry wire [Texas] (July 29)
49407. Looking for a cannon [California] (July 29)
49344. Need Help with a small powder coating repair issue [New Jersey] (July 29)
49303. Recreating French Bronze [Canada]

(July 29)
49265. Refinishing an enamel bowl with food-safe coating [California] (July 29)
49249. Cleaning vintage sterling caps over mother of pearl rosary [Texas] (July 29)
49064. Refinishing a blue toilet [California] (July 29)
49014. Vegetative Growth in Acid Copper [Pennsylvania]

(July 29)
48938. Clean black gunk from pitting on bowie knife [New York] (July 29)
49419. EN coating the inside of a diesel fuel tank [New Jersey] (July 25)
49418. What primer for painting anodized windows inside? [Australia] (July 25)
49166. How is a steel or SS outboard motor shaft masked so that hard chrome plating occurs in specific area only [Massachusetts] (July 25)

6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS

49792. Best stainless steel/finishing to handle molten NaCl [Singapore] (August 30)
49826. Electropolishing solution for porous nitinol material? [Florida]

(August 29)
49825. Basic information about CED? [India]

(August 29)
49824. Electroless nickel for oil industry valves [Iran]

(August 29)
49791. Analyzing amount of silver removed from silver cyanide by AAS? [Malaysia]

(August 29)
49790. Extraction of silver from silver nitrate liquid [India]

(August 29)
49784. We need to apply "brown gold" deposit [Italy] (August 29)
49764. Sn immersion for pcb substrates? [Philippines] (August 29)
49751. Is White Bronze a good alternative to nickel plating? [UK] (August 22)
49750. Alloy Digest Sourcebook: Stainless Steel [China] (August 22)
49749. Chemicals which are found in galvanization mist [Turkey]

(August 22)
49728. How to remove chloride from silver cyanide bath [India] (August 22)
49668. Electroless Nickel Boron Coating [India] (August 20)
49714. Non-plated light reflective surface [California] (August 19)
49695. Surface energy of chrome? [Indiana]

(August 19)
49694. Protection for outdoor plaster/concrete sculpture [Alabama]

(August 19)
49687. Grey finish on 2024 Aluminum [Florida]

(August 18)
49669. Argon or vacuum more inert for high temperature treatment? [UK] (August 18)
49667. Science project: Production of Sulfuric Acid [Malaysia] (August 18)
49649. How to melt ore particles of gold with chemicals or acids but not by heating [India] (August 18)
49688. Issue on no coat on tip [Philippines] (August 15)
49680. Is 7075 Aluminum Compatable with Limonene? [Pennsylvania]

(August 15)
49624. Effect on pH of the system with increasing Cu2+ concentration [UK]

(August 13)
49610. How can I get HCl 20% to 30%? [India]

(August 11)
49609. Leaching gold 24 hours...how about electro motor? [Indonesia]

(August 11)
49608. FDM Rapid prototyping question [Malaysia]

(August 11)
49594. 10% Nitric acid stored in aluminum tank [Florida] (August 11)
48912. Platinum plating for high voltage (~1000V) electrophoresis [Canada] (August 11)
49597. Shelf life determinants of electronic PCBs [Pakistan]

(August 8)
49596. Jewelry business research: Rhodium [New York]

(August 8)
49595. Aluminum okay material of construction for food dehydrator? [Canada]

(August 8)
49593. How to buy rhodium so I can make rhodium plating solution? [Iran]

(August 8)
49529. Reaction between HNO3 and ferrous sulfate [Iran] (August 8)
49585. Recovery of rhodium from spent pen-plating solution [Turkey]

(August 7)
49584. DI water and Aluminum reaction releases gas !! [Georgia]

(August 7)
49579. Why black precipitate during electrochemical machining? [India]

(August 7)
49547. Carbon treatment of copper plating bath [Minnesota] (August 6)
49548. Anti pit agent for watts bath? [Iran]

(August 5)
49546. Is RoHS compliance the only method to state that the material is non hazardous? [India] (August 5)
49405. Increase the whiteness of rhodium plating [India]

(August 5) 2nd Request
49490. Electroforming micro gas turbine components [Utah] (August 5)
49447. Nickel Chloride from nickel hydroxide? [California] (August 5)
49495. Welding nickel plated steel tubing [Canada] (August 1)
49150. Electrodeposition of Ruthenium 20 microns thick [UK] (July 31)
49467. Nickel (steel) plating of aluminum profiles [India] (July 31)
49446. Is there any alterantive to inhibitors for pickling, and regarding surface finish [India] (July 28)
49430. Corrosion detection on inside of the shell cs shell of titanium lined urea reactor [India]

(July 25)

6c. K-12 SCIENCE PROJECTS, GRAMMAR & HIGH SCHOOL STUDENT QUESTIONS

49623. A Titanic situation... [Australia] (September 5)
49823. Potassium iodide reaction with iron(III) chloride? [Malaysia] (August 29)
49781. The Best Penny Cleaners? [Georgia] (August 29)
49772. Rusty nails [Florida] (August 26)
49693. Silver Nitrate Solution [Australia] (August 19)
49607. What is in citrus fruits, and how does it affect pH of saliva? [Australia]

(August 11)
48959. How does pH affect rust [Australia] (August 5)
49502. School project on energy transformers [Australia]

(August 1)
49429. Separation technologies for obtaining 100% gold? [Macedonia]

(July 25)

More Letters?

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0. CORROSION, COMPATIBILITY, CHOOSING A FINISH . . .

1. PREPARATION . . .

2. INORGANIC FINISHING PROCESSES . . .

3. ORGANIC FINISHING PROCESSES . . .

4. POST-TREATMENTS

5. SUPPORTING ISSUES