We Provide Top Quality Anodizing in St. Paul, MN

Our metal finishing processes for our anodizing services include:

Multi-Color Anodizing (on one part)

Nor-Ell has a unique process of combining multiple colors (black, clear, gold, green, etc.) on the same part to create colorful, durable products, enhancing your product and brand recognition. This process can include from two-color to multi-color parts. This process is ideal for face plates, control panels, cover plates, labels, and decals. Even multicolor logos and graphics can all be anodized onto the same part creating striking, durable, and unique branding and labeling. For available samples that demonstrate the extensive possibilities for color and graphics, contact Nor-Ell.

Anodizing-Type II

Sulfuric anodize, referred to as Type II anodizing, is formed by using an electrolytic solution of sulfuric acid at room temperature and a current density of 15 to 22 Amps per square foot. The process can run for 30 to 60 minutes depending on the alloy used. This produces a clear coating, depending on sealing. Typically 1/2 of the coating thickness will build up per surface and 1/2 will be penetration.

Type II sulfuric anodizing provides several desirable qualities including:

  • Corrosion Resistance (336+ hours salt spray resistance per ASTM B117) 
  • Surface Durability 
  • Excellent Dye ability (yielding deep, rich colors) 
  • Electrical Insulation

Sulfuric anodize coatings can be sealed to enhance corrosion resistance, lock in dyes, or both. Hot water seals produce the clearest sulfuric anodize while sodium dichromate yields a yellow-green appearance. Sodium dichromate is generally a better seal.

There are hundreds of governmental, industrial, and commercial anodizing specifications in use, each with their own method of specifications for coating, seals, dyes. Anodizer will recognize the Type II designation indicating a sulfuric anodize, Class 1 to specify natural color or no dye, and Class 2 to indicate a dye. This anodizing meets Mil-A-8625.

Sulfuric anodizing is compatible with many aluminum alloys for anodizing with the exception of high-silicon die-cast alloys such as 380. The fewer alloying elements, the higher the clarity and depth of color of the anodized coating.

Color Anodizing

Nor-Ell can provide a wide variety of colors. Some colors include clear (aluminum) anodizing, black, red, green, and gold. If you have a special color to match, call us for professional assistance.