Commercial Painting – Enamel Paint

Enamel Paints

Enamel alkyd paints are good, all-around paints that dry to a hard gloss.

common characteristics for these popular commercial paints are:

  • Fast drying
  • Flake and chip resistant
  • Resistant to dirt, abrasion and impact
  • Easy to apply

Enamel paints that offer these characteristics arise from the alkyd binders used in these paints. As you may recall from previous blogs, alkyds are derived from alcohols and organic fatty acids. Both paints use medium aliphatic hydrocarbon solvents.  We rely to the Commercial Enamel when conditions are a little more demanding.

Uses and Characteristics

These enamels can be used on metals (aluminum, steel, galvanized), masonry, concrete, plaster and wood. We use them in many industrial applications, including:

  • Interior walls and ceilings
  • Exterior surfaces
  • Machinery and equipment finishes
  • High performance architectural applications
  • Floors
  • Pipes, railings, and racks

These paints come in various colors, including a very useful high-gloss black. The Industrial Enamel lost only 180 mg in the ASTM D4060 abrasion resistance test (on a steel substrate), and registered 290 psi adhesion in the ASTM D4542 test. It resists dry heat to 200°F and passed the tests for exterior durability and flexibility.

Application

Remove surface contamination via washing or blasting. Sand glossy surfaces dull. Seal greasy stains, remove rust, fill drywall cracks, sand and fill wood, and allow new concrete to cure for at least 30 days (or try applying a concrete primer sooner). You should wipe down plaster with a vinegar solution followed by a water rinse. You need to remove any existing mildew — a bleach solution does the job.

As mentioned, priming is required before applying these paints as topcoats, with the exception of wood surfaces, where you can omit the primer. Start with heavy-duty filler on concrete block and sealer on concrete floors. For interior plaster and poured concrete walls, use a masonry primer. Caulk exterior gaps between doors, trim, windows and any other through-wall openings. Caulk gaps in interior walls, ceilings, crown molding and other trim pieces. You can apply interior caulking after the primer coat. Apply two coats of the enamel after the primer dries.

Application is pretty easy, which is one reason we like these paints. Do not apply A11 Series when the temperature is 50°F or less, but you can go down to 40°F for the B54Z Series. Relative humidity should not exceed 85 percent. Apply as follows:

  • Brush: natural bristle
  • Roller: 1/4- to 3/8-inch nap with lambswool cover and solvent-resistant core
  • Airless spray:
    • A11: 1,800 psi through a .017- to .019 inch tip, reducing the enamel up to 5 percent if needed
    • B54Z: 2,500 psi, .015-inch tip, no reduction
  • Conventional Spray (B54Z only): Binks 95 gun, #66 fluid nozzle, 63PB air nozzle, 50 psi atomization pressure, 20-25 psi fluid pressure, no reduction

You’ll want to stripe-coat crevices, sharp angles and welds. If spraying, aim for a 50 percent overlap on each pass, and cross-spray at right angles if necessary.

Aim for a coat thickness of 4 to 6 mils wet and 1.6 to 3 mils dry. You will get about 250 to 400 square feet of coverage per gallon. The paint should be dry to the touch in an hour or two, depending on temperature and humidity. You can recoat after 8 hours, and the paint fully cures in a week. An unopened can of the Sherwin Williams enamels should last 36 months if stored at moderate temperatures.

Clean up using mineral spirits.