How To Coat Engine and Small Parts for Rust Prevention with Black Oxide

Black Oxide Coating Engine and Small Parts for Rust Prevention
Black Oxide Coating Engine and Small Parts for Rust Prevention

When it comes to working on old cars, the battle against rust is never-ending.

In this Hagerty DIY video short, Davin Reckow walks you through blackening your steel and cast-iron parts with black oxide in order to add a layer of protection against rust and corrosion.

What is Insta-Blak 333

Insta-Blak 333 is an immersion/swab-on blackening solution that results in a smooth satin black finish on tools, steel and cast-iron surfaces.

Use Insta-Blak 333 to:

  • Coat metal items with a glossy, grey-black finish
  • Blacken metal parts at room temperature in only 1–5 minutes
  • Achieve clean, smut-free finishes and dimensional stability
  • Reduce heating and energy costs
  • Avoid hazardous caustic fume
  • Blacken cold- and hot-rolled steels, cast iron, powdered metals, tool steels, and sterling silver

Insta-Blak 333 is a black-oxide process designed to make in-house blackening simpler, faster, and more effective while still achieving an aesthetically pleasing black finish.

One gallon of un-diluted Insta-Blak 333 concentrate can coat approximately 400–500 sq. ft. of metal part surface.

EPi offers 2-liter trial kits and 5-gallon short-run production kits for short-term projects. Learn more about what is included in the trial kit and the short-run production kit.​

More info on the Insta-Blak 333 product here: https://www.epi.com/black-oxide/steel/room/insta-blak-333/

Using Insta-Blak 333 to Blacken Steel and Cast Iron

How To Blacken Steel and Cast Iron Using Black Oxide Coating

  1. Clean

    In a steel container, thoroughly clean the parts in a 10% by volume solution of E-Kleen SR 148-E and 90% by volume of water. The cleaning time will depend upon the type and degree of soil present on the metal surfaces and the concentration and temperature of the E-Kleen SR-148-E solution.

  2. Rinse

    Using a plastic container, rinse the parts for 1-2 minutes in clear running room temperature water.

  3. Activate (optional)

    Using a plastic container, activate the surface of the parts in a 20% by volume E-Prep 258 solution and 80% by volume water for 2 minutes for optimal activation at room temperature.

  4. Rinse (if Activated)

    Using a plastic container, rinse the parts for 1-2 minutes in clear running room temperature water.

  5. Blacken

    In a plastic container, blacken the parts in a 10% by volume solution of Insta-Blak 333 and 90% by volume of water at room temperature for 2-5 minutes.

  6. Rinse

    Using a plastic container, rinse the parts for 1-2 minutes in clear running room temperature water.

  7. Seal and Finish

    In a steel container, seal the finish and enhance the depth of blackness.

    Option 7a. For an oily finish: use E-Tec 501
    Option 7b. For a slightly oily to a semi-dry finish: use E-Tec 503
    Option 7c. For a soft, non-tacky, dry-to-the-touch finish: E-Tec 504 or E-Tec 505+

    Place the blackened parts into the E-Tec solution of your choice, and agitate 6-12 times up and down (about 1-2 minutes).

    Air dry for 15-30 minutes.

    Typically, 24 hours later, the part will be blacker as the oil absorbs into the blackened finish

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