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3M™ Cavity Wax Plus

Protect your customers’ investment. Protect your shop.

  • In collision repair, effective car corrosion protection is critical. Applying three coats of 3M™ Cavity Wax Plus to all internal areas at risk of corrosion is a great way to protect your customers’ investment, your shop and your reputation. Cavity Wax Plus applies easily from a convenient aerosol can, and will not crack, chip, or peel. It is also self-healing – it reflows into cracks and crevices for continuously reliable coverage. For applying even coats inside narrow and hard-to-reach cavities, use the 3M™ Cavity Wax Plus Applicator Wand Kit. All automotive OEMs recommend applying corrosion protection material to internal portions of repaired or replaced metal panels. Three quick coats of Cavity Wax Plus is all you need to help ensure that your work meets these OEM specifications, and can save you thousands of dollars in costly comebacks.

Corrosion Protection You Can Trust

Without Cavity Wax Plus

  • Cavity wax results

    Without Cavity Wax Plus

    This is what happens to steel panels when they are exposed to salt fog during industry testing. Corrosion like this can quickly form inside unprotected automotive parts such as doors or frame rails. Since these areas are out of sight, it can easily spread. The result: a very costly comeback, and a tarnished reputation for you and your shop.

With Cavity Wax Plus

  • How to prevent rust on vehicles

    With 3 coats of Cavity Wax Plus

    3M™ Cavity Wax Plus 08852 has been tested according to ASTM B117 and SAE J2334 industry test methods. Steel panels coated with Cavity Wax Plus withstood 1500 hours of continued exposure to salt fog (ASTM), as well as environmental cycle testing under SAE J 2334 conditions with no significant corrosion.

Consistent Protection for Hard-to-Reach Areas

  • Cavity wax how to video
    Watch It in Action

    Nearly all automotive OEMs require cavity wax after repair, including in commonly overlooked areas such as narrow channels and hidden welded flanges. Watch how the 3M™ Cavity Wax Plus Applicator Wand Kit makes it fast and easy to apply 3 even coats of cavity wax inside blind cavities.

  • Cavity wax is just a part of effective corrosion protection for your shop. View our operating procedures (SOPs) – both video and in printable form – for applying cavity wax, seam sealers, undercoating and anti-chip coatings, plus technical tips which are especially important when matching OEM seam bead appearance.

Where do you apply cavity wax?

  • Where to apply cavity wax on vehicle

    • How much cavity wax should you use?

      For a typical mid-size sedan, you might expect to use the following amounts based on three coats of 3M™ Cavity Wax Plus:

      • Upper frame rail: about 1/3 to ½ of a can (volume varies by make & model)
      • Sectioning areas: about 1/3 can (volume varies by repair)
      • Lower frame rail (full replacement): about 3/4 to 1-1/2 cans (volume varies by make & model)
      • A, B and C pillars: about 1/3 of a can (volume varies by make & model)
      • Rocker panel: about 1 -1/3 cans

  • Best places to apply cavity wax on vehicle

    • How much cavity wax should you use?

      For a typical mid-size sedan, you might expect to use the following amounts based on three coats of 3M™ Cavity Wax Plus:

      • Hood perimeter: about 1/2 of a can
      • Outer door panel perimeter: about 1/3 of a can
      • Deck lid perimeter: about 1/3 of a can
      • Fender wheel arch: about 1/10 of a can
      • Quarter panel wheel arch: about 1/8 of a can

3M™ Cavity Wax Plus Featured Products

  • This non-hardening, self-healing coating will not chip, peel or crack, and is designed to cover and protect internal joints, hem flanges and compromised e-coats where corrosion can form. A convenient aerosol spray can eliminates the need for bulk spray equipment.

  • Corrosion protection is especially important in places like internal door panels and structural frame rails. This kit features 24” and 34” wands with 360-degree applicators to make it fast and easy. An additional 8” wand is great for flooding and sealing more accessible joints.

Tech Tips for 3M™ Cavity Wax Plus

3M™ Cavity Wax Plus is designed to be easy to use and to incorporate into your existing collision repair processes. To make it even easier, here are some commonly asked questions that we’ve heard from technicians and shop owners who are successfully using Cavity Wax Plus in their operations.

  • A: 3M™ Cavity Wax Plus Applicator Wands are designed to last for multiple uses. After each use, simply invert the can and spray into a clean towel to clear excess material from the wand.

  • A: As a collision repair shop, there is no way to replicate the complex multi-bath e-coating processes that OEMs use to protect against corrosion. Furthermore, common repair processes such as grinding and welding will compromise the e-coat applied by the OEM. This makes the proper application of cavity wax critical for protecting against internal corrosion and costly comebacks.

    All automotive OEMs recommend applying corrosion protection material to internal and unprotected panels following repair and replacement procedures.

  • A: 3M™ Cavity Wax Plus was tested according to ASTM B117-97 specifications – a test where metal samples treated with Cavity Wax Plus were subjected to 1500 hours of continuous exposure to salt fog in a controlled corrosive environment. These treated panels showed no significant corrosion.

    Also, 3M™ Cavity Wax Plus features a thick but non-hardening formula that will not chip, crack or peel and adheres to surfaces regardless of orientation. This material is self-healing, meaning it adapts as the metal in the vehicle expands and contracts. This maintains a protective film regardless of environmental conditions on the outside of the vehicle for reliable coverage that lasts.

  • A: In accordance with nearly all OEMs, 3M recommends applying at least three coats of Cavity Wax Plus to all unprotected metal surfaces. This ensures the self-healing material will provide adequate coverage for the life of the vehicle.

    Another helpful guideline for using 3M™ Cavity Wax Plus is to estimate approximately. ¼ can per standard quarter panel, ¼ can per door panel, and less than half of a can for a lift gate.

  • A: The 24” and the 34” wands included in the 3M™ Cavity Wax Applicator Wand Kit feature small applicators built in at the ends which distribute the material evenly in a 360-degree radius. This ensures coverage on all sides of the cavity, regardless if you are able to visually inspect it. The additional 8” wand included in the kit delivers a powerful stream that is excellent for flooding and sealing joints.

  • A: 3M™ Cavity Wax Plus has been tested in environments near spray booth application areas with no effect on the painting application process. It has also been tested with no adverse effects on freshly painted panels that have been properly baked following paint company guidelines. If you anticipate the cavity wax will remain in contact with cured paint for an extended period, you should test it first in an inconspicuous area or mask off to prevent potential damage to the finish.
    To clean cavity wax from paint, it is best to wipe off the surface using a mild solvent such as mineral spirits or a VOC-approved cleaner. Air dry paint system results may vary.

  • A: 3M™ Cavity Wax Plus should be applied after the paint repair has been completed and during the final assembly process. This ensures access to areas that may not be accessible later.

  • Important Note
    There are of course many factors and variables that can affect an individual repair, so the technician and repair facility need to evaluate each specific application and repair process, including relevant vehicle, part and OEM guidelines, and determine what is appropriate for that repair.

Need More Information on Corrosion Protection?

If you have additional questions about 3M™ Cavity Wax Plus, corrosion protection or anything related to collision repair, we’re happy to help. To contact us, or to view more information about 3M™ Collision Repair products and solutions, click to the right. We look forward to working with you!