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0. The HEAD TABLE topic: "Choosing a finish, corrosion"
• Want gold colored finishes without use of gold - October 26
• 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
• Q&A about iPhone Finishes open Q. - September 13
• Internal hydraulic tank rust prevention open Q. - August 27
• What would make Brass magnetic?
open Q. - August 24
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1. The PREPPERS' tables
1a. MECH PREPPERS' topics: "Grinding, polishing, vibratory finishing, buffing, honing"
• Repair brushed stainless finish open Q. - October 31
• Stainless steel vibratory finishing Q&A
open Q. - August 6
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1b. CHEM PREPPERS' topics: "Cleaning, pickling, etching, phosphatizing, activation"
• Pickling solutions for copper & brass - November 25
• How to determine whether component is zinc phosphated or manganese phosphated open Q. - November 5
• Zinc phosphate coating is black and peels off 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
• Pickling and bright dipping of copper open Q. - September 23
• Parker Parcolubrite -- history of zinc & manganese phosphate open Q. - August 20
• Suitable sodium nitrite levels to inhibit corrosion - August 17
• Electropolishing of Tungsten Carbide
open Q. - August 14
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1c. THE NAYSAYERS' topics: capping, plugging, masking, taping
• How to mask workpiece holes in black anodizing?
- November 14
• Plating of stainless steel tube damages inside surface - October 27
• Masking/Stop off for anodizing on complex parts
RFQ: Kentucky - October 24
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2. The HARD stuff: metallic & inorganic finishes
2a. STAINLESS, TITANIUM, CORROSION-RESISTANT METALS PROCESSING
• 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: Miami - October 19
• Passivation for type 420SS stainless - October 15
• Electropolishing and Chemical Etching Processes for Cobalt Chromium - October 13
• Citric Acid vs. Nitric Acid Passivation - October 3
• Phosphoric acid & sulfuric acid electropolishing of stainless steel - September 18
• Procedure for electropolishing stainless steel - September 16
• Anodizing titanium to green color -- Q&A's
open Q. - September 6
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2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• Black rubs off anodized parts
- November 25
• Problems in Plating on Aluminum, including alloy selection - November 21
• Large Plate anodizing problems
open Q. - November 21
• Defect in shiny anodized product
- November 21
• Sealing Aluminum to prevent oxidation? - November 9
• Problems in cold sealing of anodized aluminum - November 9
• Problems achieving shiny/glossy anodized parts
- October 31
• 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
• Teflon Coating on Aluminum open Q. - October 2
• Anodizing supplier is RoHS compliant but not RoHS certified? open Q. - September 29
• Looking to permanently whiten aluminum open Q. - September 23
• Failed Taber testing on hard anodizing open Q. - September 18
• Two-step black color anodizing Q&A, Problems & Solutions open Q. - September 15
• Dissolving aluminum with caustic soda - September 15
• Reduce anodize thickness by leaving in tank with power off? - September 14
• Chromate Conversion Coating of Cast Aluminum: Problems & Solutions open Q. - September 14
• Gold hard anodising with anti-bacterial silver open Q. - September 14
• I need to to know exact chemical composition for MIL-DTL 5541 conversion coatings
- September 1
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2c. ELECTROPLATING and ELECTROFORMING
• Zn25 vs ZnNi12 - Expected lifetime for marine indoors open Q. - November 27
• Acid Zinc Plating turns gray in 3 months
- November 25
• Adhesion No Good for Nickel Plating on Neodymium open Q. - November 25
• Zinc-Nickel Plating and Chromating Problems & Solutions open Q. - November 21
• Carbon treating silver plating solution with activated carbon cartridges open Q. - November 21
• Zinc Plating has white & red rust without a cause open Q. - November 15
• Roughness in copper-nickel plating on zamak - November 13
• Tin Plated Parts are Turning Black open Q. - November 11
• Silver plating with Auxiliary Anodes
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
• Zinc plating thickness vs. salt spray resistance - October 26
• 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
• Black stain spots in satin chrome, plus burning open Q. - 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
• Alkaline zinc plating thickness - October 13
• It takes an hour to zinc barrel plate in ammonia chloride open Q. - October 11
• How to electroplate onto Tungsten-Carbide
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
• Nickel plating peeling problem - September 27
• 'Skip' problem when doing black passivation in stainless steel baskets
open Q. - September 26
• Formula for Woods Nickel Strike - September 21
• Yellow shade in decorative chrome plating - September 20
• Copper plating staining & oxidation problem, bright dip fails open Q. - September 19
• Nickel adhesion to silicone open Q. - September 7
• Zinc plate rubs off on thumb
- September 7
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2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• 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
• Epoxy separating from Electroless nickel after thermal stress exposure open Q. - September 14
• Need mirror finish electroless nickel plating on inner walls of holes - September 9
• ENIG (Electroless nickel / immersion gold) & ENAG Plating
open Q. - September 8
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2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
• 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
• Electroplating onto sputtered Titanium & Copper thin films pulls them off
open Q. - September 9
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2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
• 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
• Lead (Pb) in Hot Dip Galvanizing
open Q. - September 4
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2g. BLACK OXIDE, BLUING, COLORING, PATINAS, NITRIDING
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
• Paint ooze out in CED process
open Q. - November 21
• How to Increase DFT Paint Thickness in Cathodic Electrodeposition (CED) system? - November 11
• Rusty Anodes in CED (cathodic electrodeposition) / Troubleshooting Coating Process open Q. - November 10
• CED E-coat air pockets/air trapping
- October 2
• Electrodeposition/e-coating (CED) issues & problems
open Q. - August 17
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3b. POWDER COATING
• 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
• Cure time after lacquer process before salt spray test - September 27
• Need longer-lasting lacquer for gold plating open Q. - September 11
• Misc. problems in CED (cathodic electrodeposition) coating - August 5
• Electrophoretic lacquer as a gold substitute?
open Q. - July 27
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3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• How many micron thickness reduction after rub test on painted panel? open Q. - October 25
• Plastisol & Solvent Ink Formulas & Improvements open Q. - October 15
• Will paint withstand while moving a vehicle top of it open Q. - September 14
• FBE Pipeline Coating Issues open Q. - September 12
• PVDF Coatings. What are they composed of?
- September 2
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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? - September 3
• 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.
• 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
• 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
• IGA/EGP testing to ASTM F2111
- September 18
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5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• Change Hexavalent to trivalent chrome? Chrome Reduction process - October 11
• Wastewater treatment issues: Cyanide destruction questions open Q. - September 14
• Ion Exchange / DM plant calculations open Q. - September 6
• pH of DM water is a mystery - August 30
• Mixed bed De-ionization: How to separate cation resin from anion 2ND REQUEST - August 17
• Table of Water Resistivities open Q. - July 27
• Can RO water be used in manufacturing phosphatizing chemicals?
open Q. - July 20
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5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
• 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
• RoHS -- is the chromium in 6061 / 5052 aluminum hexavalent? open Q. - August 29
• How to remove chrome stains from hands & arms? - August 24
• Can Trivalent Chromium degrade into Hexavalent Chromium?
open Q. - August 1
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5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• 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
• Heating open-top tanks Q&A - September 2
• Does DM water have lesser heat transfer properties?
open Q. - September 1
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5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, HISTORY, ETC.
• 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
• What is the meaning of MFZn2-E open Q. - October 17
• Verifying a Bond Path Analysis equation? open Q. - September 26
• Zinc Plating specification QQ-Z-325 open Q. - September 16
• Hanson Van-Winkle Munning (H-VW-M) memories & memorabilia
open Q. - September 10
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5f. W...W...W...WORD OF THE WEEK
5g. MOSTLY METALLURGY; Heat Treatment
• 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 rhodium sponge?
- November 21
• Recovery of fine floating gold open Q. - November 9
• Can gold be reclaimed from old ceramic dishes with gold trim - October 17
• Acid testing for gold, silver & precious metals open Q. - October 8
• Extracting gold from copper - August 24
• Refining silver from smithing, plating, mine sludge
open Q. - August 18
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6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
• 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
• Chrome over Black Chrome or vice-versa for highlighting open Q. - September 19
• "Frosted Duco" Finish" / National Resophonic 'Duolian' - September 18
• Model railroading: Effect of oxidation of nickel silver on its conductivity? open Q. - September 18
• Can I un-polish my polished ring? open Q. - September 18
• Restore Silver damaged by bleach ... toothpaste is the answer - September 14
• Removal of clearcoat on copper cookware - September 14
• Pewter cleaning, finishing & polishing - September 13
• How can I make copper turn black?
- September 7
• Silver polish (Tarn-X) stained my stainless steel sink - September 6
• How to Give Aluminum an Aged Look?
open Q. - September 4
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6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
• Electroplating on complex geometry, a microlattice structure
- November 27
• Achieve uniform thickness in Cobalt-platinum electroplating
open Q. - September 12
• Electrodeposition of Bismuth, Bismuth Plating Baths open Q. - July 29
• How to make potassium gold cyanide
open Q. - July 29
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6c. K-12 Science Projects, Grammar & High School Student Questions
• 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
• Hand painted art on a vehicle open Q. - September 11
• How to clean/restore C Jere metal sculpture
open Q. - September 9
• Corten sculpture/art & landscaping Q&A
open Q. - August 2
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7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
• 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
• How to identify and learn about antique wrought iron lamp?
- November 11
• Paidar Barber Chair Restoration: Q&A's and Successes - November 9
• Antique icebox Q&A's, Problems & Solutions
- November 9
• Maker's mark on Spanish gothic chandelier
open Q. - November 9
• Stiffel lamp Q&A's
- November 9
• Toxic effects of boric acid on feral cats open Q. - November 7
• Home Comfort Parts Needed RFQ: California - October 27
• Monarch Stove Parts Needed RFQ: Kentucky - October 27
• FB Rogers engraved silver plated pitcher open Q. - October 22
• Black Powder Cannons
open Q. - October 17
• Identifying rings/hallmarks
open Q. - October 15
• Boric acid, etc. for dog ear infections - October 14
• Bleach (sodium hypochlorite) attacking steel hull boat open Q. - October 7
• Why is this penny silver?
- September 16
• Need Sweet Spirits of Nitre (the traditional folk medicine) - September 1
• Unexpected color change in acid solution for soil digestion open Q. - August 24
• Sedgwick Residential Elevators Parts & Maintenance RFQ open to all Massachusetts - August 20
• Restoration of Vintage Soda Fountain open Q. - August 20
• Can't remove old plastic protection film from stainless steel - August 17
• I have a 1998 penny that looks silver
open Q. - August 16
• Rewiring a lamp with no access
- August 1
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Note: For 2 weeks RFQs are reserved for Advertisers.
If no advertiser responds in 2 weeks the RFQ is open To all readers.