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0. CORROSION, COMPATIBILITY, CHOOSING A FINISH . . .
• Max. Temp for plated silver Thanks! Resolved :-) - July 22
• Powder Coating vs. Liquid Paint - July 21
• Chemical resistance of nickel plating - July 18
• Which stainless steels are Magnetic - July 2
• Need Chicago screws in 3 colors RFQ Krakow, Poland - June 17
Coating for Spillway Gate Chains open Q. - June 16
• 202 SS or 304 SS for Baby Cutlery items open Q. - June 14
• Anti-corrosion coatings for Railway Track open Q. - June 13
Galvanic Compatibility of Aluminum & Stainless Steel - June 13
Why don't air conditioner condensers suffer galvanic corrosion from aluminum fins on copper tubing? - June 6
• Galvanic compatibility of aluminum guards on copper gutters open Q. - June 3
See more threads about "Corrosion, Compatibility, Choosing a Finish"
1. PREPARATION . . .
1a. MECHANICAL PREP [GRINDING, POLISHING, VIBRATORY FINISHING, BUFFING, HONING]
• Grinding hard Chrome with grinding oil vs water miscible open Q. - July 18
• Formula for polishing and buffing compounds - July 16
• Very High Bond tape doesn't stick to mirror polished stainless steel - June 21
• Is there any Roughness Standard under N1 / Ra 0.025 ? open Q. - May 24
• What VDI Finish is required for light pipes? open Q. - May 12
• How to dull a stainless steel finish - May 9
• Need to do Deburring of Titanium RFQ San Luis Obispo CA - April 27
• Problems with stainless steel cut wire media in magnetic tumbler Thanks! Resolved :-) - April 13
See more threads about "Mechanical Prep [grinding, polishing, vibratory finishing, buffing, honing]"
1b. PRETREATMENTS [CLEANING, PICKLING, ETCHING, PHOSPHATIZING, ACTIVATION]
• Oversize bore developed during phosphating open Q. - August 6
• Surface Activation for Phosphating open Q. - July 27
• Manganese phosphate coating: issues and answers open Q. - July 26
• Zinc Phosphate coating problems & issues on aluminum open Q. - July 18
• Additives to Anodic Cleaning Solutions - July 12
Sludge Issues in Zinc Phosphating - July 4
• Electrolytic cleaning: anode to cathode ratio - June 3
• Mn phosphating formula for couplings for pipes & treads open Q. - May 29
• Alternatives to Phosphating open Q. - May 27
Zinc Phosphating: Yellow Stain only on GI sheets open Q. - May 27
• Want to make alkaline ball burnishing compound open Q. - May 23
• Can't phosphate high carbon steel open Q. - May 23
• Bright dip for Fe-Cr-Al Alloy wire? open Q. - May 16
See more threads about "Pretreatments [Cleaning, Pickling, Etching, Phosphatizing, Activation]"
1c. MASKING, RACKING, TAPING, PLUGGING, PHOTOSENSITIVE MASKS
• Masking material / method for electroless nickel plating open Q. - July 25
• Etching problems with PCB tin resist open Q. - July 18
• How to mask glass bangles for PVD coating open Q. - June 18
Tape is causing Anodizing defects - May 12
See more threads about "Masking, Racking, Taping, Plugging, Photosensitive Masks"
2. METALLIC & INORGANIC FINISHING . . .
2a. STAINLESS STEEL & TITANIUM PROCESSING
• Electrical Properties of Passivated Stainless Steel - July 20
• Hydrofluoric acid vs. ammonium-bifluoride in cleaning & pickling - July 20
• Activation of stainless steel for plating open Q. - July 8
Dark frosty cloud dull finish in electropolishing open Q. - July 3
Stainless steel passivation problem: color inconsistent - June 28
• Stainless Passivation Temperature Ranges - Why is 90-120 °F excluded? - June 28
Titanium galling & anodize/oxidize wear resistance - June 28
• Electropolishing 304 stainless steel, or alternatives to it - June 21
Need titanium bolts & washers blackened RFQ: Tucson AZ - June 9
'Frosted marks' from electropolishing? open Q. - June 8
See more threads about "Stainless Steel & Titanium processing"
2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• Anodizing current stuck at 1/4 of what it should be open Q. - August 6
• Tin plating on Aluminum -- is intermediate layer of copper needed? - July 29
• Alkaline etch of aluminium prior to powder coating Thanks! Resolved :-) - July 27
• Anodizing on reflectors - July 23
• Spalling of sulphuric acid anodizing open Q. - July 23
• Remove dye but not electrocoloring from anodized aluminum open Q. - July 20
White Powder/Salts on Anodized Aluminum open Q.
• 7075-T6 Poor anodising appearance related to minor differences in composition? - June 23
• Need Phosphoric acid anodize ASTM-D-9399 RFQ: Thailand - June 17
• Discoloration of MIL-5541 Alodine - June 13
• Can chem-film resist ultrasonic cleaning? - June 12
• Problems with Alodine/Iridite/Chem-film and Blind Holes - June 9
• Salt spray test hours for anodized aluminum - June 3
• Aluminum Alloy Rotogravure Cylinder Problems & Solutions open Q. - June 3
2c. ELECTROPLATING and ELECTROFORMING
• Hard chrome plating has high coefficient of friction, not low open Q. - August 6
• Residue when Drawing a Tinned Copper Wire open Q. - August 4
• Plating time too high in alkaline non-cyanide zinc plating open Q. - July 29
• Precipitating stannic ion from tin bath open Q. - July 29
• How to specify Conductive Black Zinc open Q. - July 28
• Cadmium plating and trivalent chromate - July 27
• Immersion gold plating Q&A's, Problems & Solutions - July 20
Really bad adhesion and lack of shine in Hard Chrome plating open Q. - July 19
Nickel plating over copper flash history - July 16
• True that cast iron can't be Zinc Plated? open Q. - July 16
• Copper plating on Inconel adhesion problem open Q. - July 15
• Discoloration of bright acid tin plating - July 12
• Platinised titanium (or niobium) anodes for hard chrome plating? open Q. - July 12
• Effect of Temperature on Alkaline Zinc Plating Operation - July 4
2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• Electroless nickel-boron plating open Q. - August 9 yesterday
• A method for electroless zinc plating using ionic liquid - open Q. - August 7
• Need help with electroless/immersion tin plating open Q. - July 20
• Immersion gold plating vs. electroless gold plating - July 9
• EN Plating on Aluminum shrunk the parts but increased hole diameters - July 4
• Palladium activation & Plating on Plastic open Q. - June 26
• 'Contact' plating questions open Q. - June 21
• open Q. - August 7 >• Stability Problems with Electroless Palladium Solution open Q. - June 17
• Heat treatment of Electroless Nickel for 400-500 Vickers - June 6
• Poor adhesion of Electroless Nickel Plating onto steel - June 2
• Electroless Nickel Plating for wet sour service open Q. - June 2
• Electroless nickel plating is turning black, tarnishing open Q. - May 2
• Chrome plating peels off of ABS+PC - April 5
2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
PVD coatings: color control - July 22
• How to get Black PVD finish - May 22
• Masking in PVD process open Q. - March 25
• Need to patch up the leakage in vacuum chamber open Q. - March 22
Diamond Like Carbon (DLC) Coating Coming Off After Steam Autoclave - March 16
• Pinholes in base coat for vacuum metallizing on ABS (February 7)
2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
• Hot dip galvanizing: what is reasonable dross & ash material loss? open Q. - August 9 yesterday
Spotting, Blackening of Hot Dip Galvanized Fasteners open Q. - July 16
• Pickling/galvanizing 304 stainless steel - July 9
• Need re-galvanizing of metal shelving RFQ Limpopo, So. Africa - July 9
• Lifespan of galvanized sheet metal? - June 24
• Continuous Sheet Galvanizing: wrinkling/creases/heat buckling problem open Q. - June 16
• Some Galvalume Panels Are Turning Black open Q. - June 8
• Types of zinc used for galvanizing: PWZ vs.GOB for solar profiles - June 2
• Surfactants used in preflux and blanket flux Thanks! Resolved :-) - May 30
• Spinning and rolling to clean threads after galvanizing - May 27
Galvanizing defects: black patches open Q. - May 20
• What is an Ash Box (in Hot Dip Galvanizing) - April 24
See more threads about "Galvanizing, Aluminizing, Hot tin dipping"
2g. BLACK OXIDE, BLUING, COLORING, PATINAS, NITRIDING
• Black Oxide process: removing dust efficiently open Q. - July 27
• Mid temperature blackening smut issue open Q. - June 13
Rust on black oxide parts open Q. - June 12
• Black oxide problems on 4340 steel open Q. - May 13
• Steam Homo Treatment vs Black Oxide Treatment - April 6
• Black oxiding of hardened steel is brown open Q. - March 3
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
E-coating over Zinc or Zinc Cobalt Plating -- Problems & Solutions open Q. - August 9 yesterday
• Water spots & water or paint flow marks after curing - July 16
Chalky, ashy CED (cathodic electrodeposition) coating - July 12
• Need CED coating service in Chennai RFQ Chennai India - June 16
• Random adhesion failure in Electrodeposition coating open Q. - April 15
3b. POWDER COATING
• Blisters/ Peeling of Powder Coating on Zinc Plating open Q. - June 23
• Powder Coating Galvanized Steel open Q. - May 17
Necessity for primer with powder coatings? open Q. - April 19
• How to prevent corrosion of dully powder coated CRCA panels from acid fumes? - March 29
• Powder coat adhesion problem on zinc plate - February 20
• Powder coating on cast iron calipers open Q. (February 3)
3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
• Clear coating brass, copper and bronze open Q. - July 3
• Clearcoat for polished brass & copper bathtubs open Q. - June 27
Water spot problem in CED open Q. - April 4
• Need electrophoretic lacquer on alligator clips RFQ Akron OH (February 7)
3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• Repairing damaged PVDF Coating open Q. - July 29
• How to make wrinkle paint open Q. - July 20
• Sublimation coating formula for ceramic mugs - July 16
• Need custom tins for liquor company RFQ Jacksonville FL - July 2
Eliminate Pin Holes on Painted Wheels open Q. - June 27
• Plastisol Mixing Formulas and Improvements open Q. - June 6
• How to produce plastisol ink, pvc ink, and water based ink - May 29
• Paint moisture problem open Q. - May 14
• Hologram-like defect in automotive paint - April 25
• "Passivating" carbon steel using Citric Acid open Q. - April 12
• Can You Paint a Car with House Paint? open Q. - April 11
• Zinc rich primers in submerged service on steel ships open Q. - March 20
See more threads about "Painting, Printing, Adhesives and Other organic coatings"
4. POST-TREATMENTS
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
• 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]
• How to improve the solderability of tin electroplating? open Q. - July 16
4c. STRIPPING, REWORKS, ETC.
• How to remove conversion coating used as maskant when anodizing? - August 6
• Cleaning Tin Stain from Nickel-plated Aluminum open Q. - July 29
• Chemical to remove nickel plating from silver or brass jewelry? - May 12
• How to remove gold from copper? open Q. - March 23
• Stripping tin from copper (tin resist on PCB won't maintain normality) - February 17
• Stripping Nickel From Invar open Q. (February 11)
• Stripping nickel electroplate from Kovar open Q. (February 1)
5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
• Simple test for presence of clear chromate - July 27
• Soak Cleaner / Degreaser: Alkalinity test & oil content - July 27
• Distilled water good enough for analysis open Q. - June 25
• Thickness measurement of gold & EN on copper open Q. - June 7
• Analyze Chrome Plating Bath; Determine Sulfates open Q. - June 6
• Chem filmed panels fail salt spray test - May 30
• Platinized titanium anodes for electroplating: buying, making, testing open Q. - May 29
• Analyze cobalt and nickel metal separately open Q. - May 26
• Making sulfuric acid anodizing solution Thanks! Resolved :-) - May 13
• Measuring equipment for silver plating brightener? open Q. - April 18
• Method to identify tin plating versus nickel plating - April 12
See more threads about "Analysis, Lab technique, QA, Salt spray testing"
5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• Ferrous Chloride vs. Ferric Chloride for reducing H2S levels open Q. - August 6
• Trivalent Chromium vs. Hexavalent -- what are the differences? open Q. - July 27
Defects on test panel left in the water - June 2
• Can Trivalent Chromium degrade into Hexavalent Chromium? - May 3
• Dangers of drinking deionized water open Q. - April 19
• Methods for pH measurement in D.I. water - April 15
5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
• Safety of Galvanized Steel in home-made DIY smokehouse - July 16
• Mercury Poisoning from thermometers open Q. - May 31
• Metallic taste when wearing copper bracelet open Q. - May 24
• Is chrome plated drain cover poisoning my cat? - May 15
• Chromate poisoning from concrete work - April 10
• Fumes from Nichrome wire? - March 23
• I'm allergic to gold - March 12
Fumes from stainless pot left on burner sickened me - February 25
5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• Materials of construction for pump for zinc phosphate - July 18
• Looking for small custom titanium anode baskets RFQ: Guatamala - June 7
• Sludge buildup in phosphating piping - June 3
• Heating/cooling coil material for chrome plating - May 20
• Sodium hypochlorite (bleach) piping problems - May 19
• Maximum safe watt density for zinc plating solution heating - May 10
• Passivating electroless nickel tanks; anodic protection - May 3
• Heating and Cooling of Chrome Plating Tanks RFQ: SP, Brazil - May 2
• Ideal Sequence for Alkaline Zinc Plating - May 2
• Hard Anodize Tank Design - March 25 Inquirer often helps others, so especially deserves our help
• Sodium Dichromate Seal Tank Liner Materials and a compatible filter (February 9) Inquirer often helps others, so especially deserves our help
• Water Evaporation Estimates at Sub-freezing Temperature (February 3)
5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, ETC.
• Phosphatizing standards -- MIL-DTL-16232 - August 9 yesterday
• Is MIL-PRF-23377 equivalent to BMS10-11? open Q. - August 4
• Meaning of plating spec abbreviation MFzn8S open Q. - June 12
• How to Make Artificial Sweat and Conduct Testing? open Q. - June 2
• Swedish Standard St2 / St3 open Q. - May 2
• MIL-C-5541: Will It Work On Copper - April 13
• Cadmium Plating spec QQ-P-416 and clear chromate - March 23
• Galvanic Corrosion Test for Titanium Anodize (AMS 2487) open Q. (February 16)
• Looking for "Theory and Practice of Pulse Plating" (February 15)
• Zirconium Coating Daimler Standard open Q. (February 6)
5f. W...W...W...WORD OF THE WEEK
• How Did Kitchen Zinc become Sink? open Q. - June 26
• Definition of "passivated" in regards to metal finishing, plating, and stainless steel - March 13
5g. MOSTLY METALLURGY; Heat Treatment
• Hardening EN8 / EN9 parts open Q. - August 10 TODAY
• Hardening EN8 / EN9 parts. Q&A's, Problems & Solutions open Q. - April 1
• 316L Stainless is too spring-y open Q. - March 4
• Silver brazing flies out of gap between copper surface and nickel plated surface open Q. (February 9)
• Pinholes / blowholes in cast aluminum components open Q. (February 1)
5h. PRECIOUS METAL RECOVERY
• 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
• Why is broken catalytic converter honeycomb worthless as scrap? open Q. - May 21
• Best and Easiest way to refine gold dust open Q. - April 21
• Extracting Silver From Photographic Fixer open Q. - April 18
• Recovery from AP waste solution open Q. - March 8
• Strip and recover silver from silver plated tableware open Q. - March 8
• Gold recovery with zinc - February 21
6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
• Dishwasher ruined shiny aluminum -- How to fix it? - August 6
• Need to find Hawes Lemon Oil - August 4
• Problems and solutions in copper electroforming - July 29
• How to Fix mercury damage to gold jewelry - July 29
• Could ashes from our bonfire have ruined the paint on neighbor's car? - July 27
• Sulfur springs turned my silver jewelry black. How to fix? - July 24
Lime-Away damaged stainless steel sink - July 24
• Acid copper sulphate plating problem: copper concentration is growing - July 23
Cleaning/restoring vintage tin humpback trunk - July 18
Cleaning corroded pennies and coins - July 18
• Questions & Answers about Zinc or galvanized countertops open Q. - July 9
• 18K gold ring turned my finger black - July 8
• Kenrick 19th century cast iron open Q. - July 4
• Refinishing bronze table legs - July 4
6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
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
• White Bronze Plating, an alternative to nickel? - May 30
• Acid Zinc Plating Brightener Q&A open Q. - May 14
• Electroplating Copper Chromium Alloy Deposit? - May 13
• Reaction between hot aqua regia and sulphur open Q. - April 1
Electroplating Copper onto PVD/Sputtered Gold Substrate - March 30
• Ni-W coatings with high W content crack open Q. - March 29
• Zinc stopped plating out when voltage got high - March 28
• Ruthenium use in iPhone open Q. - March 25
• Electroplating of copper onto sputtered gold open Q. - March 22
See more threads about "Research, Thesis topics, University & Post-grad students"
6c. K-12 Science Projects, Grammar & High School Student Questions
• 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
Painting cast iron fountains / restoring rusty fountains - August 9
• Archival painting on brass and copper open Q. - July 29
Dark Reddish Spots when Bronze Casting - June 7
What do black spots on aluminum sculpture tell art student? - May 25
Strange reaction of copper BB on a bronze sculpture - May 2
Protecting Metal Birds in the Tropics - April 23
How to clean/repair C Jere metal sculpture open Q. - March 21
7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
• Want to heat homes with chemical energy - August 6
• Muriatic Acid for fiberglass shower/tub - August 6
Repair of barber chairs open Q. - July 29
Fixing Brown Rusty Water (Excess Iron) in Swimming Pool Water - July 28
• Cast Iron Cook Stoves: Where to find parts and how to restore open Q. - July 27
• WW2 Naval Ship used Silver wiring open Q. - July 24
Antique baby carriage restoration open Q. - July 23
• Copper Sulphate as Swimming Pool Algae Remedy? - July 18
Sweet Spirits of Nitre - July 12
Identifying rings and hallmarks open Q. - July 12
• Looking for a Magnet That Attracts Gold RFQ: Jeffersonville IN - July 9
• How to make bronze / History of bronze - July 2
• Hoyt Metal Co of Great Britain thermometer - July 2
Making homemade acid stains for concrete open Q. - June 30
See more threads about "Drifted off Finishing, but Interesting"
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