Larry Chesterfield
Adding Aluminum to a New Anodizing Bath: The Math and Chemistry
Aluminum sulfate is the preferred buffer to help prevent burning of parts in an anodizing bath. Larry Chesterfield elaborates.
Read MoreSolving Corrosion on Black-Dyed 7000 Series Alloy
What caused corrosion on one shop’s black-dyed parts? Anodizing expert Larry Chesterfield offers troubleshooting advice.
Read MoreInstalling an Anodizing Line that Fits Your Needs
Q: Can you suggest the best process or processes that will give us the capabilities to meet as many customer requirements as possible? Anodizing expert Larry Chesterfield answers this question.
Read MoreCathode Materials and Cathode/Anode Ratios
Q. Can we use titanium as a cathode in our Type I, II and III anodizing tanks, and what are the guidelines for cathode to anode surface area ratios?
Read More“Snowflake” Corrosion on Anodized Aluminum Parts
Q. Our customer sent us some of its anodized aluminum extrusion samples that were exhibiting a condition that looked like small snowflakes all over the part. Is this is a metal condition, or something wrong in the anodizing process?
Read MoreHow to Carefully Maintain Your Alkaline Etching Bath
Q. What should be the maximum aluminum content in an alkaline etching bath to avoid galvanized appearance (spangling) when preparing 6063 T6 extrusions for Type II anodizing?
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Water Quality in the Anodizing Process
Q. I would like to know more about the physical and chemical parameters that are used to evaluate the quality of water used in the anodizing process.
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Anodizing Clinic: Sealing with Distilled Water
Q. Can distilled water be substituted for deionized water? Our facility can create a distilled water heated bath fairly easily because we already produce distilled water for another process. A DI water bath would be much more expensive.
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Anodizing Clinic: Painting Parts After Anodizing; Seal, or No Seal?
Q. In conversations with our anodizer on the best way to seal parts for adhesion prior to painting, he referred to a choice of either a final hot water immersion at around 120°F with no seal or a hot water seal at a much higher temperature. What is the difference between the two options and which one do you think is more advantageous for paint adhesion?
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Anodizing Clinic: Measuring Color of Coatings with a Colorimeter
Q. Recently, a company asked us to match its samples so we could do work for them. According to our method, we matched the samples, but they were rejected when they were sent to the company. We were told the samples were out of tolerance. We discovered the company used a different brand colorimeter with a different color scale to measure the color. Is there a set standard in the anodizing industry for measuring and matching colors?
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Anodizing Clinic: Anodic Coating Blistering on 7075 Alloy
Q. We have recently run into a surface condition when hard anodizing 7075 machined forgings. It seems to be present primarily on the end of the part, even down into the hole. Both of these areas are machined. The condition does not appear to be evident on other surfaces. I have not seen this condition before, but it appears to me to be rather unique and something recognizable.
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Anodizing: Corrosion on Hardcoat Anodized 7000 Series Forging
Q. I sent you photos of two parts that are alloy 7050 forgings. On these parts there are spots that appeared as a result of Type III (hardcoat) anodizing that were not present before anodizing. They look like corrosion of some sort, but the corrosion looks a little different on each part. What causes these spots to appear and what measures can be taken to prevent or eliminate them after they occur?
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