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0. Choosing a finish, corrosion
61665. GI vs. CRCA for Office Metal Furniture - April 27
61629. Which coating is suitable to 1440 hrs SST - April 20
61630. Options for using tin plated terminals above the rated temperature? - March 7
19766. Galvanic Action between Galvanized and Stainless Steel? - February 8
37526. Want gold colored finishes without use of gold - February 5
20345. Salt spray or CASS hours for electrophoretic lacquer on PVD on nickel plating - January 24
16945. Need to know steel mill that produces Corten Steel open Q. - January 10
61618. White flow marks caused by new PT line
- January 5
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1. Preparation
1a. MECH PREP topics: "Grinding, polishing, vibratory finishing, buffing, honing"
38491. Microfinish comparator finishes, visual roughness guide - April 25
6053. Stainless steel vibratory finishing Q&A
open Q. - March 1
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1b. CHEM PREP topics: "Cleaning, pickling, etching, phosphatizing, activation"
48600. Phosphating: Can't dissolve zinc oxide in phosphoric acid open Q. - April 28
168/27. Zinc Phosphating: Improving the Formula - April 23
34052. Manganese phosphate coating: issues and answers open Q. - April 22
15596. Rinsing a Cleaner that contains Sodium metasilicate open Q. - April 5
61654. Manganese (II) Oxide and manganese phosphate coating open Q. - March 27
61650. Testing the concentration of titanium phosphate bath - March 20
61646. Dry Acid salt for brass and Zamak parts open Q. - March 3
61599. Zinc phosphate coating is black and peels off - February 5
56325. Removing carbon layer from mild steel - February 2
61625. Electrocleaning of Nickel
- January 4
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1c. Capping, plugging, masking, taping
61590. Masking/Stop off for anodizing on complex parts
- January 24
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2. Metallic & inorganic finishes
2a. STAINLESS, TITANIUM, CORROSION-RESISTANT METALS PROCESSING
20840. 303 Stainless Steel Passivation Problems - April 15
14182. Frosted, etched, or burnt passivated parts - Type 303 stainless steel - April 14
5358. Algae, fungus, bio-fouling in plating tanks? - April 4
51990. Parts turn black in Wood's Nickel Strike - March 21
11047. Should electropolishing voltage/amperage be ramped? open Q. - March 21
61643. Must welding tint be removed before passivation - March 7
26187. Stainless tank with NaOH at 360 °C at 128 bar - February 27
47682. Electropolishing and Chemical Etching Processes for Cobalt Chromium - February 5
14697. Chatter-like marks after electropolishing?
- February 2
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2b. ANODIZING AND LIGHT METAL TREATMENTS (Aluminum, Magnesium)
61664. Magnesium corrosion with TCP treatment - May 3
14851. Salt Spray Results vs. Panel Preparation - April 20
41531. Cleaning anodized parts with acetone and ultrasonics stains them open Q. - April 14
48664. Wet Tape Adhesion Test per MIL-DTL-5541 open Q. - April 3
61656. DI Water is Etching Anodized Aluminum in the Cleaning Line open Q. - April 3
61653. Shot Peening & Anodization to Maximize Fatigue & Corrosion Resistance of 6082-T6 open Q. - March 21
37317. Hexavalent chrome in surface of chromic acid anodized parts open Q. - March 21
61636. Black Marks on Extruded Aluminum I-Beams open Q. - March 20
9142. High Thermal Emissivity for Aluminum Electronics Boxes open Q. - March 19
34822. Temperature limit for chromate conversion coating on aluminum open Q. - March 19
56977. Mirror polishing thin aluminum sheet on both sides without warping - March 10
26894. Problems in cold sealing of anodized aluminum - March 2
61637. Halo spot in Hard Coating 6061-T6 Aluminum - February 22
43248. Two-step" black anodizing has reddish powder on it open Q. - February 19
61626. Trouble with Iridite 14-2 only on 2024 - February 19
61639. White patches only when anodizing 60xx open Q. - February 19
51573. Hard anodizing chiller sizing - February 15
3437. Anode to Cathode Ratio, Size, Spacing, Placement in Anodizing - February 12
61239. Dye keeps flaking off along with some of the anodize open Q. - February 2
61633. Methods for evaluating surface preparation steps during the anodizing process open Q. - January 29
44778. Hard Anodizing Defects: stains, flow marks - January 27
43777. White spotting on black (and red) anodising open Q. - January 11
59981. Calculating required aluminum anodizing time - January 11
53012. Electrolytic Etching of Aluminum
open Q. - January 10
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2c. ELECTROPLATING and ELECTROFORMING
37167. Nickel plating: Can't Get Enough Thickness - May 3
12243. Black Spots when Tin Plating Brass open Q. - April 27
61662. Stannous sulfate turns brown in storage open Q. - April 21
26738. Need Silver Plating to stay bright at high thickness open Q. - April 13
2454. Gold potassium cyanide gets cloudy below 3.9 pH - April 13
58336. Cadmium Cyanide Plating is Yellow instead of Olive Drab - April 12
61657. Electropurification (dummy) methods for electroplating tanks - April 6
58298. Oil mark issue in satin nickel plating - April 5
2797. Nickel Striking/plating on stainless steel problems - March 24
52562. Color gold/color gilding: Rose/pink/brown gold plating methods & issues open Q. - March 20
55624. Zinc plate steel wire then draw it, or draw it then plate it? open Q. - March 20
30106. Zinc plating thickness vs. salt spray resistance open Q. - March 10
61647. Complete Process for Cleaning, Cu, and Ag Barrel Plating on Stainless Steel - March 3
61645. Classification for evaluating corrosion in salt-laden atmosphere open Q. - March 1
0350. Nickel & Gold Plating peels off of Tungsten-Carbide - March 1
61615. Zinc plating with blue passivation is yellowish at holes - February 29
61634. Voltage spikes and amperage drops in Cu-Sn plating - February 27
39520. Copper exposed on parts that are supposed to be nickel open Q. - February 26
61640. Spotted cadmium open Q. - February 19
40169. Tin plate Blistering - February 19
48074. Hard chrome plating problems - February 19
61603. Zinc Plating has white & red rust without a cause - February 19
25163. Expired Lead Frame effect on Plating Quality open Q. - February 2
9144. Scratches on Hydraulic Cylinders: Mechanical Damage or Plating Defects? - February 1
38475. Alkaline Non-Cyanide Zinc accumulates Zinc oxide or other material at bottom of tank open Q. - January 29
28127. Alkaline zinc plating thickness - January 28
61621. Blue spot/growth on a silver plated component open Q. - January 16
61587. Black stain spots in satin chrome, plus burning open Q. - January 14
61628. Surface Area Calculations for Rough Castings
- January 4
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2d. ELECTROLESS PLATING, PLATING ON PLASTICS, IMMERSION PLATING, CHROME-LOOK SPRAYS, LIQUID METAL COATINGS
52480. Yellow Stains on Electroless Nickel Plating Inquirer often helps others, so especially deserves our help open Q. - March 21
4726. Nickel-Chrome Plating on ABS Plastics open Q. - March 19
44444. Silvering formulas using silver nitrate
- March 3
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2e. PVD, CVD, ION IMPLANTATION, VACUUM PROCESSES
61651. ZrN has sufficient salt spray test resistance but TiN doesn't - March 23
40590. Need TiN coated stainless sheets
RFQ open to all: Las Vegas NV - February 20
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2f. GALVANIZING, ALUMINIZING, HOT TIN DIPPING
55564. Titrating for the concentration of HCl in galvanizing flux open Q. - April 14
54149. Top Dross is growing since we started filtering open Q. - March 20
49192. Galvanizing buildup on MIG wire weld areas - March 11
51659. How much hydrogen peroxide to treat flux tank? - March 11
56867. Spotting, Staining, Blackening of Hot Dip Galvanized Finish - March 10
61641. Having trouble heating the flux bath - March 1
49328. Cost to open a hot dip galvanizing business? - February 20
49271. Zinc ammonium chloride requirements for galvanizing flux - February 19
20172. How tough is galvanneal steel? Will it rust if the coating is penetrated?
- February 5
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2g. BLACK OXIDE, BLUING, COLORING, PATINAS
59418. Passivation after black oxide? - March 29
54394. Black Oxide on stainless steel: problems open Q. - March 21
61635. Hot Black Oxide Issue- brownish-green parts and black spots/streaks
- February 12
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2h. OTHER INORGANIC FINISHING: Mechanical Plating, Nitriding & QPQ, Metal Spray, Zinc-rich Dip-Spin Coatings, Sherardizing, Rust Preventatives, etc.
52675. Process Comparison for Tufftriding and Nitriding open Q. - March 20
40139. Rust spots on pickled coil after a few days open Q. - September 1
26940. Sursulf Processing Q&A, Problems & Solutions open Q. - April 4
3. ORGANIC FINISHING [PAINT, POWDER COATING] . . .
3a. ELECTROPAINT PRIMING, AUTOPHORETIC COATINGS
32574. Ra Increase Caused by CED Coating
open Q. - April 5
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3b. POWDER COATING
41802. Will Tin Plating survive a Powdercoating fluidized bed? open Q. - April 30
52690. Powder Coating has roughness/bumps under it open Q. - April 22
61658. Powder Coat Paint issue -- missed areas, fisheyes? open Q. - April 16
42644. Pinhole problems in powder coating - February 13
39593. L.a.b. CIELAB color issues: gloss variation, matching different finishes, etc. - February 4
61627. Powder Coating of "Black Annealed" CRS
- January 3
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3c. LACQUERS, CLEAR COATS, ELECTROPHORETIC TINTING, ANTI-TARNISH
47125. Electrophoretic lacquering for costume/imitation jewelry open Q. - April 27
61193. Protecting metal surface with thousands of tiny grooves that trap dirt - March 1
23047. Solvent name for reducing the pH of electrophoretic bath
open Q. - February 2
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3d. PAINTING, PRINTING, ADHESIVES AND OTHER ORGANIC COATINGS
40308. Gluing Stainless steel to chrome/copper/alloy plate - March 5
46505. Sublimation Coating Introduction, FAQs and Q&A open Q. - February 23
15909. Plastisol & Solvent Ink Formulas & Improvements - February 5
6926. Painting anodized aluminum
- February 1
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4. POST-TREATMENTS
4a. CHEMICAL POST-TREATMENTS [CHROMATE CONVERSION COATINGS, RUST PREVENTATIVES, PATINAS, COLORIZING]
NNNNN. Chromating of Zinc-Nickel Plating Q&A open Q. - April 27
37772. Can zinc plated parts go on for zinc phosphating? - February 4
34323. Verifying anti-tarnish for copper plating
open Q. - January 13
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4b. BAKING AND NON-CHEMICAL POST-TREATMENTS [HYDROGEN EMBRITTLEMENT AND DE-EMBRITTLEMENT, ANNEALING, WHISKERS, SOLDERING, REFLOWING]
334/31. How to improve the solderability of tin electroplating? Peel-off & Blistering - April 27
28294. Post plate baking of EN coatings
- June 25
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4c. STRIPPING, REWORKS, ETC.
61648. How to strip nickel from copper plate open Q. - March 5
33203. Need paint stripper not harmful to plastic open Q. - March 3
22156. Stripping electrophoretic CED coatings
open Q. - February 2
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5. SUPPORTING ISSUES
5a. ANALYSIS, LAB TECHNIQUE, Q.A., SALT SPRAY TESTING
8904. Salt Spray Hours vs. real life exposure - May 3
44485. XRF and Plating Thickness Measurement open Q. - March 7
50132. ASTM B117 Salt Fog Test Chamber Operational Q&As, Problems: Salt Spray Woes open Q. - March 3
0644. Copper Sulphate Test on Gold Plated Part open Q. - March 1
35573. Acceptance criteria after salt spray test - February 19
61638. Need lab SOPs for electroplating shop - February 16
36184. Is titration the best method to analyse copper content of ore? - February 5
41654. Determine % Nitric Acid. Titration? Conversion factor? open Q. - January 29
6060. Test for Type 316 vs. 304 Stainless Steel open Q. - January 9
18778. Analyzing acid tin baths -- bright and matte open Q. - January 9
61619. Salt Spray and Cyclic Corrosion Test for Assembled Parts
January 4
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5b. WASTE & WASTEWATER TREATMENT, POLLUTION CONTROL
59691. Sodium Metabisulfite and its reaction with water open Q. - March 26
7063. Recovery of copper from electroforming solution
- January 7
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5c. SAFETY ISSUES, EMISSIONS, TOXICITY, ENVIRONMENTAL IMPACTS
54906. Stainless pot left on burner; are the fumes dangerous? - April 23
61661. Strange taste & throat closing while wire sanding mystery metal - April 23
55787. Has anyone been diagnosed with Parkinsons after working in the chrome plating industry? open Q. - March 10
19953. What is the toxic effects of mixing muriatic acid and bleach? - March 4
6852. Cyanide Poisoning Issues - February 2
47195. Toxic Lead & chrome in coffee makers & espresso machines?
- January 13
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5d. PLANT & PROCESS ENGINEERING, CONSTRUCTION
27638. Production of silver potassium cyanide from silver nitrate
open Q. - January 23
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5e. QUESTIONS ABOUT SOFTWARE, SPECS, BOOKS, EDUCATION, INDUSTRY STATS, HISTORY, ETC.
51970. Need specification QQ C-320 "Electrodeposited Chromium" open Q. - April 27
443/76. Boeing finish codes Q&As open Q. - April 17
61642. What is Alcoa Alumilite Black 326R1? open Q. - March 1
26629. What is the meaning of MFZn1-SC open Q. - February 16
61632. Does MIL-C-5541 forbid a "Do Not Etch" instruction? - January 26
61506. FAIR 9102 Question re. Chromating & Anodizing
- January 19
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5f. W...W...W...WORD OF THE WEEK
57140. Procedures QF-09-162 & QF-09-163 for nitric & chromium analysis?
- March 30
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5g. MOSTLY METALLURGY; Heat Treatment
25525. Tin/nickel interdiffusion Q&A - April 23
12545. Annealing 316 Stainless Steel Tubing
- March 1
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5h. PRECIOUS METAL RECOVERY
14022. Recover gold from gold plated rims open Q. - April 12
43983. Is this ore/rock Palladium & Rhodium open Q. - March 1
20033. Recovery of fine floating gold open Q. - January 27
50167. How to separate copper from silver
- January 11
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6. NON-INDUSTRIAL ISSUES
Hobbyists, DIY, Around Home
8937. How to refinish cast iron and cast bronze fireplace surrounds - April 27
372/05. Sterling silver vs. silver plate -- How to tell? - April 27
11988. Cleaning an old copper kettle for apple butter open Q. - April 25
38061. Silver polish (Tarn-X) stained my stainless steel sink - April 23
61663. Mustard Stripped the Copper Plating from Tart Pan - April 22
61659. Vintage Kerosene Lamp: cleaning Copper Plating & Japanning - April 16
25553. Nickel plating of copper cooking utensils - April 14
34076. Artistic copper plating from hydrochloric acid - April 14
7229. How to refinish brass lamps - April 6
20967. Gold/Silver plating of natural objects Q&A - April 5
20193. Chroming carbon fiber/plastic - March 30
21868. Rings Made from U.S. Coins - March 29
0338. Zinc plating & chromating of Carburetors - March 26
30965. Can't remove old plastic protection film from stainless steel - March 21
52028. Staining on anodized aluminum window frames - March 21
26845. How to paint a stove top - March 20
61649. Electroplating as forge welding prep - March 20
62644. Oxide Finishing - March 3
23897. Brass lamp seems to be brass plated copper - February 12
56879. Have Blue Gun, Want it Chrome appearance open Q. - February 8
4148. Ruined the finish on my stainless steel fridge - February 8
61631. How to Remove Zinc Phosphate from Frying Pan - January 20
41214. Sticky surface after anodising - January 19
21595. Remove black antiquing from my Citadel class ring open Q. - January 18
38108. Jewelry cleaner took finish off ring - January 7
21437. "Rainbowing" and "Bluing" Stainless Steel
- January 7
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6b. RESEARCH, THESIS TOPICS, UNIVERSITY & POST-GRAD STUDENTS
61652. Coating stainless steel part using PTFE dispersion open - March 26
52366. Hard chrome plating: Volts, Amps, Anode-to-Cathode Distance - March 21
3795. Achieve uniform thickness in Cobalt-platinum electroplating
- February 15
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6c. K-12 Science Projects, Grammar & High School Student Questions
0865. Brass electroplating for amateurs and students - April 20
53795. Which chemicals can produce power? open Q. - April 5
28434. Electroplating with copper sulphate for science project
- February 24
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6d. The Artists' Corner
50348. How to Make Stainless Appliances a Champagne Gold Color - April 16
61624. Antique French cast metal lamp figurine is what metal? - January 14
0085. Copper electroforming is too red
- January 4
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t
7. DRIFTED OFF FINISHING, BUT INTERESTING :-)
9941. Why is this penny silver? open Q. - April 25
61660. How to fix/weld this lamp metal open Q. - April 21
1178u. How to remove silver tarnish - April 14
18481. Is our sulfur well water safe for our dogs? open Q. - April 14
10153. Sedgwick Residential Elevators Parts and Maintenance? open Q. - April 13
32413. About sweet spirits of nitre (the traditional folk medicine) - April 13
61655. Stovetop Cast Iron Trivet Maker and History? open Q. - March 29
41759. Where to get replacement leg caps for vintage chrome dinette - March 25
11377. Taking antique brass beds apart open Q. - March 22
44464. Who invented words? - March 21
13393. Remove Brown "Varnish" (periostracum) from Shells open Q. - March 7
60399. Bleaching Saguaro (Cactus) Skeletons - February 22
11284. Normal weight 2015d nickel shrunk to size of a penny open Q. - February 2
29370. Is 'P star M' ring that's marked 14K actually solid gold? - January 29
29370. Identifying rings/hallmarks - January 27
33143. Stiffel lamp Q&A's open Q. - January 22
20323. Brass Finishers in the 1800's / 19th century
open Q. - January 13
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