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0. CORROSION, COMPATIBILITY, CHOOSING A FINISH . . .
• Stainless steel grades suitable for very dilute salt water? - March 21
• What would make Brass magnetic? - March 20
• Electroplating onto phosphated steel parts - March 9
• Proper fastener material for Ti plate to Aluminum Extrusion?
- February 19
• Coloring Nickel Plating, like red or blue open Q. - January 26
• Matte black finish for mild steel rivets
- December 11
• Galvanic Corrosion between nickel & aluminum
open Q. - November 26
• Want black bolts with no oil on them - November 21
• Black finishes for bolts and hardware Q&A - November 17
• Copper weathervane staining aluminum church steeple open Q. - October 26
• SPCC vs. SGCC vs. SECC steel for computer cases open Q. - October 20
• Galvanic Corrosion between Galvanized Steel and Aluminum
- October 19
1. PREPARATION . . .
1a. MECHANICAL PREP [GRINDING, POLISHING, VIBRATORY FINISHING, BUFFING, HONING]
• De-rusting/De-scaling of Heat Treated Parts open Q. - February 28
• Difference between Ra and Rc - surface roughness - January 26
• Cracks in hard chromium platings not visible, but are deep in NDT open Q. - January 10
• Mechanical finishing of body jewelry and wires open Q. - December 25
• Surface finishes N1 thru N12 and their equivalents in Ra - November 27
• Polishing chromoly chandelier
- October 30
1b. PRETREATMENTS [CLEANING, PICKLING, ETCHING, PHOSPHATIZING, ACTIVATION]
• How to do Bright Dipping of Brass - March 22
• Turbulent flow in strip-line electrolytic cleaner? open Q. - March 9
• Need Macro-Etch Chemical Process Consultant RFQ: Ohio - March 2
• Electropolishing the inside of a long tube - February 27
• Zinc Phosphate coating problems & issues; Q&A's open Q. - February 11
• Boiling Diamonds in Acid to Clean Them open Q. - February 7
• Manganese Phosphate coating color uneven, and not taking in spots
- February 7
• Want good salt spray hours from phosphating without oil - February 6
• Pickling & passivating of welded carbon steel pipe open Q. - January 19
• Need details of 'the 7-tank process - January 16
• Coating Weight Specs. How to increase/decrease zinc phosphate coating weight
- January 4
1c. MASKING, RACKING, TAPING, PLUGGING, PHOTOSENSITIVE MASKS
• How to selectively patina copper (darken it) - March 2
• Best Masking Materials & Methods for Aluminum Anodizing - February 11
• Masking material / method for electroless nickel plating - February 8
• Need TURCO 5580-G masking product
- February 6
2. METALLIC & INORGANIC FINISHING . . .
2a. STAINLESS STEEL & TITANIUM PROCESSING
• Passivation Stains on 17-4 PH Stainless Steel
- March 9
• Electropolishing with citric acid - February 19
• Electrolytic etching of titanium - February 11
• Electropolishing/deburring of hypodermic needles - January 10
• Stainless steel laser etch and passivation Q&A - January 10
• Removal of Heat Treat Scale from Stainless Steel
open Q. - December 13
• Anodizing titanium black in color - December 8
• Haziness or Cloudiness on Type III Anodized Titanium - December 2
• Passivating long small dia., 316L SS tubing
- December 1
2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• Anodized Aluminium edges not taking dye very well
- March 20
• Problems achieving shiny/glossy anodizing - March 19
• "Neutralizing" sulphuric anodizing solution with nitric acid - March 5
• Bulk anodizing for aerospace
open Q. - March 2
• Need black anodizing that is UV-proof - March 1
• Bright dip stains the aluminum with grain pattern - March 1
• Roller for adhesion test for chromate conversion coating - February 26
• Problems in cold sealing of anodized aluminum - February 25
• Crazing/cracking of anodized Type II film during powder coating baking
open Q. - February 24
• Bending aluminum: best alloys and lubricants open Q. - January 19
• Aluminum anodizing: Constant current vs. controlling the voltage - January 11
• Thickness of Alodine/Iridite/Chemfilm on Aluminum - January 3
• MIL-DTL-5541 Chem film fails humidity test - January 2
• Burning problem in Hard Anodizing of Aluminum
open Q. - January 1
2c. ELECTROPLATING and ELECTROFORMING
• Partial Plating of Chrome on copper base cylinder
open Q. - March 20
• Chloride Nickel Plating is black and burned.
open Q. - March 20
• Some problems in Zinc-Nickel Plating
- March 20
• Zinc plating with chromate: is temperature causing the corrosion? - March 18
• Platinum plating on silver Q&A Problems & Solutions - March 18
• Brighteners used in Silver Plating bath open Q. - March 10
• Blisters in Nickel Plating after Heat Treatment open Q. - March 10
• Need Ductility in Nickel Electroplate - March 6
• Nickel Carbonate not Dissolving open Q. - March 2
• Wood's Nickel Strike Bath Analysis & Maintenance - March 2
• Brass plating peels off -- Q&A, Problems & Solutions - March 2
• Non uniform thickness problem in electroplating - March 1
• Gold isn't bright when plating leaded stained glass - March 1
• Chrome thickness variations on gravure cylinders
open Q. - February 26
• Choosing Plating Rectifier Voltage & Current - February 24
• Zinc plating thickness vs. salt spray resistance - February 23
• Nickel Electroplating is peeling off Stainless Steel
- February 19
2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• Plating Electroless nickel onto stainless steel powders - February 28
• Hydrogen Embrittlement vs. Electroless Nickel Plating - February 11
• Spray chroming with silver nitrate - January 3
• Can citric acid passivate a stainless tank used for electroless nickel plating? - October 26
• Palladium activation & Plating on Plastic - October 1
• Heat treatment of Electroless Nickel Plating open Q. - September 23
• Electroless gold plating (autocatalytic) open Q. - September 18
• Composite electroless nickel-PTFE plating open Q. - September 13
• Electroless Nickel Plating of Aluminum without Zincate - September 9
• Barrel plating on plastics/ABS - September 5
• A method for electroless brass plating? - September 3
2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
• PVD gold color control and matching open Q. - February 14
• PVD coatings: color control
open Q. - December 7
• Need base coats and top coats for vacuum metallizing RFQ South Africa - November 20
• How to make glass in colors? open Q. - November 15
• How to get Black PVD finish open Q. - September 2
2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
• Want to do Hot Dip Galvanizing Off and On - February 24
• Want pre-galvanized sheet with 720 hours salt spray resistance - February 21
• Zinc adherence defect on edges of galvanized steel sheet open Q. - February 19
• Galvanizing defects: black spots, lumps, streaks
open Q. - February 17
• Hot dip galvanizing flux Q & A's
- February 17
• Hand re-tinning of copper cooking utensils? open Q. - January 31
• Safety in a Zinc hot-dip galvanizing process open Q. - January 26
• Can stainless steel be hot dip galvanized? open Q. - January 9
• Galvanizing flux bath has iron contamination
- January 8
2g. BLACK OXIDE, BLUING, COLORING, PATINAS, NITRIDING
• Does black oxide on stainless fasteners improve resistance to galling? open Q. - February 9
• Blackening formulas for steel and cast iron - January 2
• How to do smut-free mid temp black oxide on wood screws - December 25
• Black Ox problems due to lot variations in type 300 SS? - December 20
• Black Oxide Coating Thickness - November 18
• Which oil BLACK OXIDE finish? open Q. - October 2
• Black oxide is salmon colored. Is copper the problem? - September 19
2h. OTHER INORGANIC FINISHING: Mechanical Plating, QPQ, Metal Spray, Zinc-rich Dip-Spin Coatings, Sherardizing, etc.
3. ORGANIC FINISHING [PAINT, POWDER COATING] . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
• Why does zinc & cathodic e-coat lose adhesion after humidity test? open Q. - March 8
• E-coating on anodized aluminum? - December 8
• Low pH Problem & Dropping Anolyte Level in CED Bath - December 1
• Excessive foam formation in UF1 dip tank
open Q. - November 23
• How to perform Acid MEQ of CED Bath manually? open Q. - November 3
• E-coating over Zinc or Zinc Cobalt Plating -- Problems & Solutions - September 27
3b. POWDER COATING
• Chromated & Powder coated ADC12 Aluminum doesn't pass 366-hour salt spray test open Q. - January 31
• Industry specs for powder coating thickness and testing methods? open Q. - January 9
• Sublimation heat transfer paper for powder coating? open Q. - November 15
• Powder coating burns during cutting & slotting of profiles - September 18
3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
• E-Coating Zinc Alloys -- Q&A; Problems & Solutions open Q. - March 6
• DFT problems in CED open Q. - February 18
• Clear coating silicon bronze open Q. - September 27
• How to make long lasting Dye Gold Plating on Imitation Jewelry open Q. - September 5
3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• Painting plastic imitation wicker furniture? open Q. - March 8
• Need Formula for NC Thinner & Auto Thinner open Q. - February 25
• Plastisol stays sticky after curing
open Q. - December 12
• Solar Heat Reflective Paint Consultant RFQ London U.K. - December 6
• Q&A on MIL-P-23377 primer - December 6
• Scratch marks are appearing in ABS Parts after painting open Q. - October 2
• Can You Paint a Car with House Paint? - September 16
4. POST-TREATMENTS
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
• Post-dip to improve color of imitation gold plating? - December 20
• Help with dye over zinc plating - December 2
• Yellow/gold Iridite leached to clear - October 12
• Answer to why Black Chromate turns green - July 15
• Is Zinc Plating with Chromate Conversion Coating RoHS compliant? open Q. - July 9
• Chromate conversion on cadmium not adhering open Q. - March 23
• Generic solution for chromating brass - March 22
• Bright Dipping of Brass: some shop problems open Q. - March 20
4b. BAKING AND NON-CHEMICAL POST-TREATMENTS [HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]
• Post Cadmium Plating Tarnish from Baking open Q. - March 2
• Reflow of Tin-Lead Solder open Q. - March 2
• Matte tin turns into bright with reflow open Q. - January 12
• Are tiny solid blobs of tin detrimental to PCB?
open Q. - January 4
• Hydrogen Embrittlement and the Lawrence Gauge - November 16
• Chrome plating and Hydrogen Embrittlement Relief - September 9
• How to improve the solderability of tin electroplating? open Q. - July 16
4c. STRIPPING, REWORKS, ETC.
• Removing chrome plating from plastic (ABS) parts open Q. - March 6
• Nickel plating on brass parts looks layered.
- March 3
• What chemical is safe, cheap & best to remove zinc coating? - February 12
• Stripping Tin / tinplate from Steel open Q. - November 18
• Can sulfuric acid be used to remove nickel plating from aluminum? open Q. - October 26
• What to use as anodize remover/stripper open Q. - October 14
• How to strip chromate from silver plated finish - October 14
• Removing rhodium plating electrolytically - September 8
• Removing TiN (Titanium Nitride) coatings - August 19
5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
• Controlling iron content in hydrochloric acid - March 21
• Hull Cell Test for Cadmium Plating
open Q. - March 13
• How to know 304 vs. 316 Stainless; tests & suggestions - March 1
• Can I use NaOH solution instead of NaCl in Salt Spray test? - February 21
• Silver plating: atomic absorption analysis of silver open Q. - February 19
• ASTM B117 Salt Fog Test Chamber Operational Q&As, Problems: Salt Spray Woes - February 10
• Determine % Nitric Acid. Titration? open Q. - February 6
• Taber ASTM D 4060: conditioning aluminum coupons open Q. - February 4
• Fluoride analysis in HF/Nitric (etch for titanium) - January 30
• Maintaining and Monitoring Acid Copper brighteners open Q. - January 17
• Analyze for iron content in hydrochloric acid
- January 4
5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• Cyanide Disposal/Destruction for school lab - March 11
• How to electrowin/recover copper (plating waste) open Q. - March 2
• Caustic & aluminum recovery from cleaning processes - February 21
• Recovery of copper from electroplating & etching solutions open Q. - January 19
• Recycling of Chrome Stripping solution (HCl) - December 30
• DM System Problem: Poor OBR, short SBA life open Q. - November 20
• TDS vs PPM vs. µS? - October 14
5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
• Remove Teflon coating from Visions & Pyrex Cookware - March 14
• Is corrosion in copper water vessel hazardous?
- March 10
• Inhaled fumes from Bleach and C.L.R. accidentally mixed - February 26
• Is worn silverware a Health Hazard open Q. - February 2
• Does my silver plated flatware contain lead? open Q. - January 16
• Sick from welding galvanized steel - January 16
• Danger in Cast aluminum cookware? open Q. - December 5
• Yellow zinc hex nuts in arts and crafts projects
- November 28
• Safety of hibachi barbecue with yellow zinc screws and damper open Q. - September 22
• Permit requirements for powdercoating - September 13
• PTFE/Teflon Environmental Concerns - September 6
5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• Passivating electroless nickel tanks; anodic protection systems
- March 1
• FRP to protect "tub" from hot temperatures, pressure, rust and leaking? - February 28
• Chemical cleaning of boilers and inhibitors open Q. - February 26
• Concrete tank for zinc phosphate? - February 23
• Designing a Copper Refining Plant open Q. - February 19
• Hydrogen "Explosions" in Plating, Anodizing open Q. - February 8
• Titanium anode baskets get copper buildup in Rochelle Copper Plating - February 3
• Need design assistance on French process zinc oxide furnace So. Africa - January 16
• Avoiding Tank Overflows in Plating Shop - January 13
• 2% Sulphuric Acid in 316SS tank is turning green & smutty during Aluminium pickling - November 15
• Best way to remove lining from Chrome tank
- October 14
5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, ETC.
• Alkaline Anodizing Titanium per AMS 2488 open Q. - March 2
• International standards for phosphating processes open Q. - February 4
• BAC 5709 and Opening Oven Door to Load More Parts open Q. - December 12
• MIL-DTL-5541 Class 1A vs. Class 3 - October 8
• Phosphatizing standards -- MIL-DTL-16232 - August 9
• Is MIL-PRF-23377 equivalent to BMS10-11? open Q. - August 4
5f. W...W...W...WORD OF THE WEEK
• Thickness of CMS-02 or F4383 type T3? open Q. - March 15
• What is the Helodor 100 process open Q. - March 10
• Is there such thing as sterling silver plating? open Q. - August 30
• How Did Kitchen Zinc become Sink? open Q. - June 26
5g. MOSTLY METALLURGY; Heat Treatment
• Problems in Annealing of Copper Wire open Q. - January 26
• Is 6063 aluminum a precipitation hardening alloy? open Q. - January 11
• 316L Stainless is too spring-y - January 3
• How to decarbonize the surface of high carbon steel - December 22
• Does forging create mill scale? open Q. - September 8
• Hardening EN8 / EN9 parts. Q&A's, Problems & Solutions open Q. - August 10
5h. PRECIOUS METAL RECOVERY
• How can I produce rhodium sulfate in lab? open Q. - March 4
• Is this rock Rhodium?
open Q. - February 20
• Acid testing for silver & precious metals open Q. - February 19
• Specific gravity table for gold open Q. - January 16
• Why is broken catalytic converter honeycomb worthless as scrap?
open Q. - November 10
• Refining of silver chloride to silver metal open Q. - July 28
• Refining of Palladium and making its salt open Q. - July 16
• How to precipitate gold from HAuCl4 solution open Q. - July 12
6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
• Blackening stainless steel without using Potassium dichromate? - March 21
• Copper plating onto Silver - March 21
• What could be causing the pitting and corroding to chrome fixtures - March 15
• Stripping plating from welding clamps leaves them copper color - March 15
• How to turn 18-8 fasteners black? - March 13
• Need help painting brass! open Q. - March 10
• How to get beautiful galaxy-like vintage finish on pot lids?
- March 10
• Geneva Metal Kitchen Cabinets: Painting, Removing Dents, Parts open Q. - March 9
• Remove tin plating from copper pots, trays, cookware - March 6
• Best type of clearcoat for wheel application? open Q. - March 6
• Clear coat sealer/varnish safe for birds? - March 5
• Brown heat mark on refrigerator
open Q. - March 4
• How to paint screw heads - March 2
• Damaged finish on copper table
- February 19
• Dishwasher ruined shiny aluminum
- February 19
• Restoring a black & copper "japanned" antique finish - February 10
• How To Rust Metal like Jingle Bells & Safety Pins - February 10
• Restoring rusty cast iron wood stove, painting it open Q. - February 8
• Sealing lightly corroded aluminum engine parts with crude oil
- February 6
• Clear coating to protect rust patina finish - February 2
• Carburetor re-plating / re-coloring open Q. - January 30
• Magnetic, silver-color, 1998 penny
open Q. - January 30
• Removing Teflon non-stick coating from Glass Cookware open Q. - January 26
• Restoring the yellow dichromate finish on automobile carburetors open Q. - January 20
• D-I-Y Yellow gold engagement ring to white gold? open Q. - January 20
• Solving an electrolysis problem in home plumbing open Q. - January 18
• Acid copper plating is not responding to brightener
open Q. - January 18
6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
• Electrodeposition of Molybdenum - March 21
• Why can we copper plate iron/steel in alkaline solution but not acid? - March 14
• Nickel plates okay in one barrel, but not another
- March 14
• How do I make citric-based copper plating smooth open Q. - March 10
• Trouble with Concentration Calculations - February 20
• Electroless Nickel: need intro and technical info - January 31
• Electrodeposition of titanium remains a bust :-( - October 28
• Procedure for electropolishing stainless steel - October 26
• Silver paste on PZT blisters after firing open Q. - October 12
• Electroplating Copper onto PVD/Sputtered Gold Substrate - September 8
• Recovery of Metallic Magnesium from Magnesium Citrate. Is It Possible? - June 13
• Electrolytic Passivation of Nickel Plating - June 7
• Electroplating on 3D Printed & Stereolithography (SLA) models open Q. - June 6
6c. K-12 Science Projects, Grammar & High School Student Questions
• Why does tarnished penny weigh less than shiny one - January 28
• Science project: To rust and trust - January 6
• Copper sulphate reaction with a nail or steel wool - November 11
• Rusting in distilled water vs. saltwater - October 3
• Why can't we store electricity in water? - June 14
• How many mL of water must be added to 10 grams of NaOH to make a 0.50 molar solution? Thanks! Resolved :-) - May 23
6d. The Artists' Corner
• Repaint Cast Iron Statue from "The Little Chapel" in Guernsey
- February 28
• Can print maker prevent ink discoloration on etching plates? open Q. - December 6
• Long ridges on copper electroform
- October 17
• How to clean/repair C. Curtis metal sculpture open Q. - September 7
• Can't restore bright finish to bare aluminum piece - September 1
• Painting cast iron fountains / restoring rusty fountains - August 9
• Archival painting on brass and copper open Q. - July 29
7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
• Identifying rings/hallmarks: JA and nothing else open Q. - March 20
• "Red Mountain" Cast Iron Cook Stoves: restoration hints plus where to find parts & info
open Q. - March 11
• Stiffel lamps repair Q&A's
- March 7
• Theda Sterling Silver Medals, Crosses, Jewelry Q&A
- March 4
• About sweet spirits of nitre (the traditional folk medicine)
- February 25
• Brass Finishers in the 1800's open Q. - February 23
• Best pipe for natural gas lines: Copper vs. steel, plastic, CSST, etc. - February 19
• Barber Chair Restoration Q&A's and Successes
open Q. - February 13
• Mother of pearl button collection molding away.
open Q. - February 9
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