The finishing.com HOTLINE public forum
New postings Thursday Oct. 21
0. CORROSION, COMPATIBILITY, CHOOSING A FINISH . . .
• Need gold plating directly on titanium (October 12) open Q.
• Need high resistivity biocompatible plating on nichrome (October 10) open Q.
• Convert anodizing line to another process (September 29) open Q.
• Acid resistant coating for aluminum (September 9) open Q.
• Powder Coating tiny blades for fishing lures open Q. (August 25)
• Chrome vs. Powder Coating of Motorcycle rims (July 24)
• Need scratch resistant, conductive, black coating on copper strip (July 5) open Q.
1. PREPARATION . . .
1a. MECHANICAL PREP [GRINDING, POLISHING, VIBRATORY FINISHING, BUFFING, HONING]
• Polishing Intricate Stainless Steel Spheres and Concave Mirrors (September 28) open Q.
• Need mirror finish on Socket & Philips screws (August 29) open Q.
• Polishing copper and brass (August 25) open Q.
• What media will allow tumble finishing in 30 minutes? (August 15)
• RMS vs Ra (July 9) open Q.
• Maximum groove depth in nickel plating with diamond cutting (July 5) open Q.
1b. PRETREATMENTS [CLEANING, PICKLING, ETCHING, PHOSPHATIZING, ACTIVATION]
• Black stripe on cleaned and annealed cold rolled coils (October 12) open Q.
• Loss of weight in acid pickling (October 9)
• How to make phosphating solution (September 27) open Q.
• Problems and solutions in zinc phosphating (September 27) open Q.
• Black Oxide vs Phosphate (September 18)
• Powdered metal parts rusting after pickling process (September 16) open Q.
• Chemical & Electropolishing of Brass RFQ Thane India (September 15)
• Electroplating without acid pickling (September 14)
• Degreasing copper cylinders for chrome plating (August 21) open Q.
1c. MASKING, RACKING, TAPING, PLUGGING, PHOTOSENSITIVE MASKS
• Need masking help for anodizing (September 25)
2. INORGANIC FINISHING PROCESSES . . .
2a. STAINLESS STEEL & TITANIUM PROCESSING
• Stainless steel etching -- How To (October 15)
• Cloudiness on Type III Anodized Titanium Med Screws (October 15)
• Problems & Solutions in Passivation of Titanium (October 12)
• Electrochemical Weld Cleaning on 316L Stainless Steel (September 24) open Q.
• Anodizing titanium with trisodium phosphate (TSP) (September 24) open Q.
• Passivation of 303SS with Nitric Acid Q&A, Problems & Solutions (September 20)
• Problems electropolishing stainless castings (August 30)
• AMS2488 Type II on Titanium: maximum touch-up area? (August 29) open Q.
• Electropolishing small 4xx / 400 series stainless steel parts (August 15) open Q.
• Stainless steel laser etch and passivating (August 9)
• Electropolish, Passivate, or Chemical Polish 4140 & 4340 Steel? (July 30) open Q.
• Stainless steel passivation color inconsistent (July 30)
2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
• Anodizing a Weldment of Different Aluminum Alloys (October 15)
• Anodizing A380 vs. A360 (October 12) open Q.
• Temperature limit for chromate conversion coating on aluminum (October 11) open Q.
• Where to get glass coated abrasive paper? (October 11) RFQ Denmark Inquirer often helps others, so especially deserves our help
• Big pits on big panels in boric-sulfuric acid anodizing open Q. (October 8)
• Anodizing problem on AA 5052 Alloy (October 7) open Q.
• Plating onto Aluminium without zincate or stannate (October 4)
• White corrosion spots/pits on chromated aluminum after 1-2 months (September 29)
• Anodizing is splotchy grey, not black (September 29)
• Plating or Anodizing of Aluminum Gears (September 28) open Q.
• Hard Anodize Type 6061 Aluminum: stains (September 27)
• Film on anodized parts: is black dye tank contaminated? (September 27)
• Chemical conversion coating on top of anodizing (September 27)
• Nitric acid drag-in to dye/seal tank (September 27)
• Dyed Anodizing Color Matching Q&A, Problems & Solutions (September 27)
• Alodine, Iridite, Chem-film not sticking / rubbing off (September 27)
• Silver Plating on Aluminum: Blister / Bubble Problems (September 25) open Q.
• Only one of the parts on the rack Hard Anodizes (September 24) open Q.
• Crazing/Cracking problem in anodizing (September 22) open Q.
• Lines appear on aluminium profiles (September 19)
• What hardness/abrasion resistance from anodizing? (September 16) open Q.
• Mixing two different part sizes in the anodizing bath (September 13)
• Sulfuric Acid Anodize: Cl, F, Sulfide Limits (September 9)
• White powder on anodized finish (September 7)
• Zincating on Aluminum: Problems with 6000 series (September 6) open Q.
• Anodizing 0.003" 5052 aluminum? RFQ Palmdale CA (September 6)
• How to Chromate Conversion Coat ADC12 Aluminum (September 5) open Q.
• White dots on an anodised finish (August 23) open Q.
• Thermal conductivity of conversion coatings on aluminum (August 20)
• Anodising rectifier and power requirements (August 10) open Q.
• Problems with Color of Hardcoat Anodize (August 7)
• How to anodize 6061 T6 aluminum and what do I need? (August 7) open Q.
• Iridite 17P and RoHS compliant alternates? (August 5) open Q.
• How to eliminate anodizing appearance variations (August 5)
• Anodizing on 7000/7XXX aluminum is chipping at edges (August 5)
• Burning problem in Hard Anodizing of Aluminum (August 4)
• Can't get proper black color on hardcoat anodizing (August 3)
• Nickel Plating on Aluminum Adhesion Problem (July 30) open Q.
• Special light & glasses to reveal whether aluminum is anodized (July 24) open Q.
• Alodine is not properly coating some aluminum alloys (July 22) open Q.
• De-smutting/De-Oxidizing of aluminum (July 21)
• Anodized aluminum is inadvertently scrubbing N2O gas (July 13) open Q.
• Minimum anodizing thickness for good dark black? (July 13) open Q.
• Horizontal anodizing of aluminum sheets (July 10)
• Aluminum Anodizing flakes off when heated to 125 °C (July 7) open Q.
• Black spots in anodized aluminum profile (July 2) open Q.
• Anodized surface is powdery (July 2)
2c. ELECTROPLATING and ELECTROFORMING
• Problem of white spots after Zinc Plating (October 21) open Q.
• Granules form when acid copper plating? (October 19)
• Can we improve our tin plating Salt Spray results? (October 19) open Q.
• Nickel plating anticipated salt spray test hours (October 18) open Q.
• Pitting during use on Hard Chrome plated roller (October 15) open Q.
• What should be exact distance from hard chrome anode to cathode? (October 12) open Q.
• Maximum allowable thickness of nickel plate under silver plating (October 11) open Q.
• Zinc plating defects (Quality of metal finishing) (October 10)
• Pitting & Bubbles in Hard Chrome Plating (October 9) open Q.
• Problems with tin plating over copper or brass (October 9) open Q.
• Metal plating of babbitting (October 5) open Q.
• Our copper plating anodes are turning black (September 30) open Q.
• Conductivity of the zinc plating with chromate conversion coating (September 29) open Q.
• Want more brightness & hardness, and better LCD coverage, in HEEF-25 Chrome Plating (September 29) open Q.
• Rose gold plating is rusting (September 27) open Q. 2nd Rqst
• Acid Copper Plating Problems (September 25)
• Differences between chloride (acid) and alkaline zinc plating (September 25)
• HCl causes parts to blister (September 24) open Q.
• Nickel plating plus rhodium as substitute for silver plating (September 23) open Q.
• Very early rusting of zinc-nickel plated screws (September 23) open Q.
• Need tin plating on 100 aluminum chain saw pistons RFQ WA Australia (September 21)
• Cyanide copper solutions temperature and anodes (September 19)
• Hard chrome plating troubleshooting (September 18) open Q.
• Hard Chrome Plating on Hydraulic Cylinders Scratched by Seals (September 18) open Q.
• Need Plating onto Tungsten Powder RFQ Cohasset MA (September 15)
• Need brass plating on aluminum frames RFQ Overland Park KS (September 14)
• Nickel striking of stainless steel (September 9) open Q.
• Black spots on brass and copper plating (September 6) open Q.
• Zinc plating problem (August 29)
• Vermeil jewelry is tarnishing (August 12)
• Zn blue passivation turns yellowish (August 12)
• Tin Plating Problem (August 12)
• How to plate copper wire with lead (August 7) open Q.
• Electroforming onto silicone forms RFQ Woodland CA (August 6)
• Hard Chrome plating of zinc die castings (August 5) open Q.
• How to "Distress" Chrome Plating RFQ Cambridge UK (August 2)
• Reducing chloride concentration in acid copper bath (July 30) open Q.
• Titanium-Cadmium Plating Q&As (July 27)
• Unplated area inside blind holes is rusting (July 19) open Q.
• Alkaline Zinc Plating Q&A's, Problem: White Patches After Chromating (July 19) open Q.
• Cadmium Plating Is Peeling from Nickel Plating (July 18) open Q.
• Potassium Chloride Shortage for Zinc Plating Is there an alternative? (July 18) open Q.
• Tin plating anode problems (July 16) open Q.
• Tin plating discolors (turns yellow) (July 16) open Q.
• Zinc-Iron Plating with Trivalent Chromate fails 240-hour salt spray (July 15) open Q.
• Zinc plating failing 48-hour salt spray? (July 12)
• Bleed-out from seams after zinc plating (July 9) open Q.
• Zinc-plating appearance problems (July 5)
• Conductivity of Zinc-Nickel Plating & Chromating (July 5) open Q.
• Troubles with rose gold plating (July 4) open Q.
2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
• Electroless nickel plating testing with UAN solution (October 14)
• Electrical conduction properties of electroless nickel plating (October 14) open Q.
• Sodium Hypophosphite alternate chemical? (October 5) open Q.
• Screen printing onto Electroless nickel Plating (September 27)
• Electroless nickel to prevent high temperature oxidation of copper (September 18) open Q.
• Factors affecting Electroless Nickel deposit rate (September 6)
• Can Electroless Nickel Plating be Machined? (July 18) open Q.
• Formula for electroless nickel plating solution (July 2) open Q.
2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
• Aluminum PVD on PC Temperature Endurance (October 2) open Q.
• PVD coatings: color control Q&A's (September 18) open Q.
• Coating & Finishing of Titanium for Biomedical (August 21) open Q.
• Vacuum Cad plating adhesion problem on 13-8 stainless (July 17) open Q.
2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
• Rough & lumpy low quality galvanizing (October 15) open Q.
• Spotting, Staining, Blackening of Hot Dip Galvanized Finish (October 14) open Q.
• Aluminium addition to Galvanising Kettle (October 10) open Q.
• GP concertina wire rusts only when sent to some cities (October 10) open Q.
• Risk to galvanizing kettle from low zinc level? (September 28)
• White patches on new hot dip galvanized poles (September 23)
• Hot-Dip Tinning Problem: Crystals in molten tin tank (September 13) open Q.
• Chrome-free galvanized pipe gets black spots (August 23)
• Galvanizing kettle furnace and burner design (August 21)
• Black spot problem on hot dip galvanized mesh (August 18)
• Excessive generation of dross in zinc kettle startup (August 10)
• Get zinc out of 5000 lb mold after cooling (August 10)
• Finish on zinc coated steel coil for prefabricated housing (July 2) open Q.
• Pimples on hot dip galvanizing (July 2)
2g. BLACK OXIDE, BLUING, COLORING, PATINATING, NITRIDING
• Black oxidation layer went off after shooting test (August 5) open Q.
• Testing the quality of blackening coating (July 16)
2h. OTHER INORGANIC FINISHING: Mechanical Plating, QPQ, Metal Spray, Zinc-rich Dip-Spin Coatings, Sherardizing, etc.
• Dacromet coating questions (July 23) open Q.
3. ORGANIC FINISHING PROCESSES . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
• Misc. problems in CED (cathodic electrodeposition) coating (September 26) open Q.
• Foaming in phosphate tank causes CED defects (August 10)
• Emissivity of e-coating vs. powder coating (August 8)
• Pin holes in CED e-coating (July 4) open Q.
3b. POWDER COATING
• Powder coated steel is blistering (October 18) open Q.
• Powdercoating stainless steel Q&A's, Problems and Solutions (October 12) open Q.
• Powder coating on zinc die-castings (August 16) open Q.
• Touching up powder coating (August 10)
• Mixing powder coating colors to get a new color (August 10)
• Alternatives to powder coating (July 27) open Q.
3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
• Coatings for metal spectacle frames (August 30)
3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
• Poor adhesion between epoxy primer and urethane top coat (October 6) open Q.
• Fire and vandal-resistant coatings for rolling stock (September 20) open Q.
• Seeking Rainbow Coating on Fish Hooks (September 15) open Q.
• Candy apple coating for brushed steel (August 26) open Q.
• Training on plastisol chemistry and application? open Q. (July 7)
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
• Conductivity of olive drab chromate on cadmium (September 22) open Q.
• White colored spots on chromated zinc plating (July 23)
4b. BAKING AND NON-CHEMICAL POST-TREATMENTS [HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]
• Standards for Hydrogen Embrittlement Relief after Zinc-Nickel Plating (September 6) open Q.
• Soldering issue when using a Silver-bearing Soldering Alloy (July 9) open Q.
4c. STRIPPING, REWORKS, ETC.
• Stripping Silver Plating from brass (musical instruments, etc.) (September 25)
• Stripping the glass from a glass-to-metal seal (August 9) open Q.
• Stripping aluminum with caustic soda (July 27) open Q.
• Removal of tin plating from copper (July 14) open Q.
5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
• How to make 0.1N sulfuric acid (October 14)
• Cyanide Brass/Copper plating Solution Analysis (October 11)
• Q-Panel Envelopes...Where to buy them? (October 10) open Q.
• Determine % Nitric Acid. Titration? Conversion factor? (October 8)
• Salt Spray Test -- ASTM B117 Operational Problems (October 4)
• Titrimetric/spectrographic method for iron & copper in chrome bath (September 29) open Q.
• How to measure amount of Gold used and left in the plating bath? open Q. (September 28)
• Procedure for chromic acid and sulphate determination (September 24) open Q.
• Converting Baumé to Concentration (September 9)
• Soak Cleaner / Degreaser: Alkalinity test & oil content (September 2) open Q.
• Gravimetric analysis of gold plating bath (August 29)
• Electrical Resistance Testing of MIL DTL-5541 Chromate (August 26) open Q.
• How to Analyze/Titrate a Hardcoat Anodizing Tank (August 20) open Q.
• Caustic Etch Analysis -- aluminium anodizing (August 14)
• Converting percent by volume to oz/gal (August 9)
• How to test hard chrome without copper sulphate (July 19) open Q.
• Guidelines & best practices for purchasing a salt spray chamber (July 13) open Q.
• Dubpernell test method for chromium plating (July 10) open Q.
• Determination of sulfuric acid in chromium bath (July 5) open Q.
• Correlation between accelerated weathering & natural weathering (July 1) open Q.
5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
• Recovery of tin from waste plating solutions (September 30) open Q.
• Wastewater Treatment: Sulphate Removal from Anodizing Wastewater (September 24) open Q.
• Floating Sludge Problem in Wastewater Treatment (September 24) open Q.
• Wastewater Flow Meter Needed (August 2) open Q.
• Chromium in my Anodizing Waste? (July 18)
• Ion Exchange / DM plant calculations (July 13) open Q.
5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
• How poisonous is Potassium gold cyanide? (October 2)
• Danger from galvanized planting boxes? (September 18) open Q.
• What happens when one inhales sulfamic acid dust? (September 13) open Q.
• Stainless pot left on the burner; are the fumes dangerous? (September 7)
• Does drinking milk really help with metal fume fever? (August 29) open Q.
• How toxic is chrome plating on my faucet (August 2)
5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
• Buffer pads for McClary Easy Polisher Scrubber (October 19) RFQ Ontario
• Removing dummy cathode from nickel tank knocks the copper back in (October 19) open Q.
• Hard chrome plating: Amperage increases although Voltage is constant (October 18) open Q.
• Linear Positioning Systems for Programmed Hoists (October 11)
• Separate nitric acid from mixture of nitric & sulphuric acid (October 10) open Q.
• Is filtration required for acid zinc plating? (October 10) open Q.
• Acid etch (ammonium bifluoride) solids handling RFQ Toronto (October 9)
• Copper Plating Issue: Uneven distribution (September 29) open Q.
• M.O.C. for nitric-sulfuric tank for stripping silver (August 19) open Q.
• Chrome plating mist /fume control (August 12) open Q.
• Hard anodizing chiller sizing for 5-gallon tank (July 30)
• Tank material for hard chrome plating (July 9)
5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, ETC.
• Can I do MIL-DTL-16232 phosphatizing on galvanized items? (October 15) open Q.
• Penetrant inspection per ASTM E-1417 (October 6) open Q. 2nd Request
• Good Reference Books for Electroplating (September 21)
• Meanings of plating spec abbreviation: MFZnIII (August 31) open Q.
• Industry specs for powder coating thickness (July 29) open Q.
• NADCAP & NADCAP Audits (July 20) open Q.
5f. W...W...W...WORD OF THE WEEK
• What is Continuous Gold Plating (July 2) open Q.
5g. MOSTLY METALLURGY; Heat Treatment
• Must copper wire be annealed for drawing? (October 14) open Q.
• Need copper masking & carburizing (October 4) RFQ Chennai India
• How to anneal mild steel (September 18) open Q.
• Cast Aluminum Cookware: What Alloy is Best? (August 26) open Q.
• Post treatment of steel after quenching process (August 14) open Q.
• Inconel 718 turns black during pickling only if heat treated (August 5) open Q.
• How to separate copper from silver (July 13) open Q.
5h. PRECIOUS METAL RECOVERY
• Finding the purity of silver in silver alloys (October 16) open Q.
• Is this ore/rock Platinum, Palladium & Rhodium? (September 30) open Q.
• Want to sell a 4-pound chunk of 20% iridium (September 22) open Q.
• Cleaning gold that has been burned (August 29)
• Problems in recovering gold from soil (August 28)
• Separation of Gold metal from Immersion Gold Solution (August 23) open Q.
• How much gold in a pound of computer memory sticks (August 12) open Q.
6. CONSUMER, RESEARCH, & STUDENT ISSUES
6a. ARTISTS, HOBBYISTS, CAR BUFFS, HOME OWNERS, ETC.
• Stumbled onto good metallizing method for electroforming (October 20) open Q.
• Copper sink turned black (October 20) RFQ Underwood ND
• How to make wood finish wrinkle paint (October 15) open Q.
• Cleaning the interior of an air compressor tank (October 12) open Q.
• Finish for a copper radiator/heatsink. Cleaning copper & solder (October 12) open Q.
• Antiquing Paint / Faux Wood Finishes (October 5) open Q.
• Can Cast Aluminum be Anodized? (October 5)
• Can citric acid clean a catalytic converter? open Q. (October 4)
• Nickel plating before acid copper? (October 2)
• Designing a plating setup to plate 2" diameter plastic coins (September 30) open Q.
• Protective coating for brass elevator doors (September 30)
• Anodizing titanium to blue color (September 30)
• Chroming carbon fiber/plastic (September 28) open Q.
• Chromating carburetors/diecastings (September 21)
• Scratched and Dull Surface on Stainless Steel Refrigerator Door (September 20) open Q.
• Painting cast iron fountains / restoring rusty fountains (September 20) open Q.
• Anodizing of Aluminum Screws and Threads (September 19)
• RIT dye for dyeing? (September 16) open Q.
• Rusted sheet metal HVAC ducting (September 15) open Q.
• Painting copper gutters (September 15) open Q.
• How to darken aluminum (September 14)
• How to remove stove polish so wood stove can be painted? (September 14) open Q.
• Electroforming a complex shape in thick copper (September 9)
• Why Noxon Brass and Silver Polish Disappeared (September 8)
• Copper remains on welding clamps despite muriatic acid bath (September 6) open Q.
• Nickel plating musical instrument valves (September 5) open Q.
• How to strip Powder Coating from steel? (September 4)
• Help, my yellow brass turned pink (September 3)
• Desperately Need Gillespie Antique Restorer (September 2)
• Looking to refinish my 1950s Chambers cooktop RFQ Louisville MS (September 1)
• Strip newer paint on Geneva Metal Kitchen Cabinets to reveal original (August 31) open Q.
• New silver plated euphonium changed color almost immediately open Q. (August 30)
• Stainless steel flatware with mirror finish scratches too easily (August 30) open Q.
• Thai mid-century bronze flatware (August 26) open Q.
• Home anodizing-Truths from the experts? (August 26) open Q.
• Ruined my brass cabinet handles with vinegar (August 25) open Q.
• Melting old gold to make new jewelry (August 25) open Q.
• Paint not sticking to Ospho (August 23)
• Dark brown or dark copper patina for Nickel/Iron weld (August 20) open Q.
• How to Remove Varnish from Brass (August 19) open Q.
• Recipe for red patina on brass & copper (August 15) open Q.
• Determine & control copper concentration in acid copper plating (August 14) open Q.
• Help with unwanted rainbow hues in clearcoat (August 12)
• Need to make a silver ring look gold without using gold (August 10) open Q.
• Fastener systems for aluminum pool cages (August 9) open Q.
• Want to remove the paint from my new refrigerator (August 8) open Q.
• Help with a knife blade turned black (August 8) open Q.
• How to paint this metal mailbox? (August 7) open Q.
• Protecting metal tools from corrosion (August 7)
• Need springs for Antique baby carriage (July 29)
• Is 0.05µ gold plating "good quality"? open Q. (July 29)
• Repair discolored copper awnings RFQ Chicago IL (July 27)
• Damaged the finish on copper table -- HELP! (July 26) open Q.
• Restore gold plate/wash on sterling silver cup (July 26)
• What to to paint burners on propane stove with? (July 26)
• How to identify if old lamp is brass, copper, bronze, or cast iron? (July 21) open Q.
• Why black line on face from gold jewelry? (July 18) open Q.
• Problems & solutions in copper electroforming (July 12)
• Need shotgun barrel blued RFQ Wooster OH (July 9)
• Restoring old copper washing basin (July 8) open Q.
• Want silver plating instructions (July 7) open Q.
• Q&As about Gold Plated Flatware (July 5) open Q.
• Seeking finishing suggestions on vintage receiver restoration (July 2) open Q.
6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
• Arc coating with powders and liquids (October 15) open Q.
• Was cyanide ever used in hard chrome plating? open Q. (September 22)
• How to electrodeposit PbO2 (lead dioxide) (September 10)
• Anodized aluminum has microscopic black dots on its surface (August 30) open Q.
• Manganese electroplating (Electrodeposition of Manganese) (August 14) open Q.
• Plating onto Carbon Fiber: applications, methods, Q&As (July 30) open Q.
• Producing hardened concrete nails (July 30) open Q.
• Teflon coating of stainless steel (July 29)
• History of iron electroplating (July 19)
• When to replace magnesium electropolishing solution, or how to analyze? open Q. (July 7)
6c. K-12 SCIENCE PROJECTS, GRAMMAR & HIGH SCHOOL STUDENT QUESTIONS
• What part does voltage play in electroplating? (October 16)
• Zinc Electroplating with vinegar and salt (October 15)
• Sodium Hydroxide: How to make to 0.5 M strength (October 11)
• Building a really cheap electric arc furnace (July 12) open Q.
7. DRIFTED OFF FINISHING, BUT INTERESTING TO SOME OF US :-)
• Cost and availability of iridium (October 21)
• Hanson Van-Winkle Munning (H-VW-M) memories & memorabilia (October 16)
• Repair of barber chairs (October 13) open Q.
• Identifying rings: Marking system for rings (October 10) open Q.
• Coating tables and bar tops with thick clear pourable plastic (October 9) open Q.
• Best pipe for natural gas lines: Copper vs. steel, plastic, CSST, etc. (October 5) open Q.
• Strong welding fumes in bathroom (September 27) open Q.
• Cleaning Dirilyte Gold-tone Flatware (August 15)
• Hazmat transportation requirements & exclusions (July 21)
• Drawn platinum wire as a hinge pin on bracelets & earrings (July 15) open Q.
• Markings indicating real gold on jewelry (July 12) open Q.
RFQs reserved for Advertisers for 2 weeks, and colored Red.
Thereafter RFQs become Open To All.