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0. CORROSION, COMPATIBILITY, CHOOSING A FINISH . . .
• Coloring Nickel Plating, like red or blue open Q. - January 26
• Better corrosion resistance: zinc plating or zinc phosphating? - December 19
• 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]
• 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
• Grinding HVOF coatings open Q. - August 14
1b. PRETREATMENTS [CLEANING, PICKLING, ETCHING, PHOSPHATIZING, ACTIVATION]
• 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
• Manganese Phosphate coating is uneven, non uniform
open Q. - November 26
• Remove rust with muriatic acid (HCl / hydrochloric acid) open Q. - November 23
• Manganese phosphate coating: issues and answers open Q. - November 8
• History of Parco-lubrite, zinc phosphate, and manganese phosphate coatings open Q. - November 1
• Etching of Tungsten Problems & Solutions Q&A - October 31
• Need Pickle Inhibitors, Rodine and alternatives
- October 26
1c. MASKING, RACKING, TAPING, PLUGGING, PHOTOSENSITIVE MASKS
• Need TURCO 5580-G masking product RFQ Connecticut - January 12
• How to selectively patina copper (darken it) - November 14
• 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
2. METALLIC & INORGANIC FINISHING . . .
2a. STAINLESS STEEL & TITANIUM PROCESSING
• 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
• Aesthetic thermal browning of stainless steel open Q. - November 28
• Stainless Steel Discoloration when Heat Treating open Q. - November 26
• Electrochemical De-burring/Grinding of Micro Surgical Knife
- November 21
• Electropolishing defect in small area open Q.
- November 17
• Anodizing titanium to green color -- electrolytic pre-etch
open Q. - November 14
2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• 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
• Anodising thickness not being achieved - December 31
• Aluminum Anodizing Color Match Problems
- December 22
• Anodizing Discolorization "Leopard Spots"
- December 21
• MIL-C5541-Class 3 Question - December 20
• Chromic Acid Anodizing: Parts are too dark
open Q. - December 17
• Stains in Electrocolouring of aluminum
- December 6
2c. ELECTROPLATING and ELECTROFORMING
• Gold plating rubs right off! - January 28
• Very large black rack marks in Zinc-Nickel Plating
- January 26
• Alkaline Zinc Plating Q&A's, Problems & Solutions - January 26
• Nickel plated stainless steel batteries getting pinholes - January 26
• Plating time too long (acid zinc) - January 16
• Heavy parts chrome plate well; light ones don't open Q. - January 16
• Nickel plating Inconel Q&A: Bumps in low-stress nickel - January 14
• Silver plating delaminates from copper parts but not brass parts
- January 10
• Relationship of Plating Thickness to Current/Amperage - January 10
• ISO a Metal Plater with loooooooooong tanks! 2nd Rqst, open to all RFQ South Florida - January 7
• Why is chromium failing?
- December 25
• DI water stains Nickel plated surface
open Q. - December 23
• Nickel and Gold Plating onto Bronze Workpiece 2nd Rqst - December 19
• Nickel Electroplating is peeling off Stainless Steel - December 19
• RoHS Zinc Plating of Machine fasteners and Bolts - December 14
• Electroforming onto silicone forms/mandrels open Q. - December 12
• Zinc Plating / Electrogalvanizing Mild Steel Wire
- December 12
2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• 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
• Need help with electroless/immersion tin plating open Q. - August 21
• Electroless nickel-boron plating open Q. - August 9
2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
• 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
• 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
• Safety in a Zinc hot-dip galvanizing process open Q. - January 26
• Want pre-galvanized sheet with 720 hours salt spray resistance - January 19
• Can stainless steel be hot dip galvanized? open Q. - January 9
• Galvanizing flux bath has iron contamination - January 8
• Required Frequency of Zinc Dross Removal - December 30
• Sink roll in hot dip galvanized strip problems - December 20
• Hot-Dip Galvanizing Kettle: how to build or where to buy one RFQ - December 9
• Black/Gray Staining on Batch HDG
- November 15
• Temporarily weld/repair Galvanizing Kettle - September 21
• How to detect whether powder coating is on GI vs CRCA? - September 20
• Galvanizing flux bath has low pH & high iron - August 31
• Zinc consumption control in hot dip galvanizing - August 31
• How to reduce bottom dross in hot dip galvanizing line? open Q. - August 31
2g. BLACK OXIDE, BLUING, COLORING, PATINAS, NITRIDING
• 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
• Cold blackening on SS turns blue over time open Q. - September 6
• 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 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
• 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
• 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
• 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 silicon bronze open Q. - September 27
• How to make long lasting Dye Gold Plating on Imitation Jewelry open Q. - September 5
• Clearcoat for polished brass & copper bathtubs open Q. - June 27
• Water spot problem in CED open Q. - April 4
3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• 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
• PVC Insulation Coating Blackens Copper Wire & Cable open Q. - August 21
• Help, paint adhesion problem on HDPE open Q. - August 20
• 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
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]
• 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.
• 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
• Can't strip chrome from copper gravure cylinder open Q. - October 3
• 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
• Maintaining and Monitoring Acid Copper brighteners open Q. - January 17
• Analyze for iron content in hydrochloric acid - January 4
• Analysis of Nitric Acid in the presence of Hydrofluoric Acid open Q. - December 13
• ASTM B117 Salt Fog Test Chamber Operational Q&As, Problems: Salt Spray Woes - December 7
• MIL-DTL-5541 Chromate Conductivity Testing - November 27
• Analyze tin metal left in electroless tin solution open Q. - November 2
• Test if Alodine 1200 clear was actually done - October 17
• Determine % Nitric Acid. Titration? - September 29
• How to Analyze Resin Impregnation of Aluminum open Q. - August 14
• Distilled water good enough for analysis? - August 14
5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• 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
• Trivalent Chromium vs. Hexavalent -- what are the differences? - August 31
• Recycling of chrome sludge open Q. - August 14
• Ferrous Chloride vs. Ferric Chloride for reducing H2S levels open Q. - August 6
• 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
• 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
• Boric Acid as Eye Wash open Q. - August 31
• Mixed bleach with acid and inhaled it - August 14
• Safety of Galvanized Steel in home-made DIY smokehouse - July 16
5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• Need design assistance on French process zinc oxide furnace So. Africa - January 16
• Avoiding Tank Overflows in Plating Shop - January 13
• How to prevent contamination of Nickel Strike by copper from bus bars? - - January 1
• 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
• Need Anode Baskets for Silver Plating RFQ Watertown TN - September 7
• 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
5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, ETC.
• 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
• 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
• Is there such thing as sterling silver plating? open Q. - August 30
• 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
• 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 open Q. - August 10
• Hardening EN8 / EN9 parts. Q&A's, Problems & Solutions open Q. - April 1
• 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
• Specific gravity table for gold open Q. - January 16
• Is this ore/rock Platinum, Palladium & Rhodium?
open Q. - December 11
• 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
• 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
• Removing Teflon non-stick coating from Glass Cookware open Q. - January 26
• Dishwasher ruined shiny aluminum
- January 26
• Clear coating to protect rust patina finish 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
• Chrome redipping for wheel open Q. - January 16
• Copper plating of lead bullets, cheap & simple open Q. - January 14
• Chemical removal/stripping of chrome from bicycle parts open Q. - January 11
• Karat gold (10k-18k) electroplating using dissolving donor anode open Q. - January 11
• Making aluminum look like copper
- January 10
• Where to find ZAP professional restorer open Q. - January 9
• Which metal is safest for fireplace heat exchanger? open Q. - January 9
• How To Rust Metal like Jingle Bells & Safety Pins - January 6
• Sealing lightly corroded aluminum engine parts with crude oil
open Q. - January 4
• Painting a car with house paint open Q. - January 2
• Damaged finish on copper table
open Q. - January 1
• Penny Floor Problems & Solutions
- January 1
• Is black Hard Chrome as hard as White?
open Q. - December 26
• How to make polyresin coated real flowers
- December 25
• Thru-hull fitting w/brass hose barb & bronze valve
open Q. - December 24
6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
• 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
• 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
• 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
7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
• Theda Sterling Silver Medals, Crosses, Jewelry Q&A
- January 11
• Sedgwick Residential Elevators Parts and Maintenance
open Q. - January 10
• Cook Stoves: Where to find parts and how to restore
- January 7
• Looking for a Magnet That Attracts Gold
- January 5
• About sweet spirits of nitre
- December 31
• National Cash Registers: How to Restore & Refinish
- December 20
• Identifying rings and hallmarks: "Haven"?
open Q. - December 17
• Ribbon Speakers: Where to find conductive paint / epoxy, ribbons? open Q. - December 7
• How did copper protect ships against WWII attacks?
open Q. - November 27
• Remove plastic film (& adhesive) from stainless steel, brass?
open Q. - October 17
• Copper Sulphate as Swimming Pool Algae Remedy? open Q. - October 14
• "Living locket" -- any info available? Lock of hair keepsake - September 29
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If no advertiser responds in 2 weeks the RFQ is open To all readers.