Application of a protective coating to a car

Stone Chip and Underbody Protective Coatings

Stone chip protection and underbody protection coatings can be easily applied with 3M technology

In every body shop, there is sometimes the need to apply higher viscosity materials such as high build primers or functional coatings. This process is usually not very user-friendly and involves a high amount of cleaning work - and cleaning is a task that can't be invoiced for.

  • Application of a protective coating using 3M Accuspray

    See how to apply protective coatings with our 3M™ Accuspray™ Pressurised HGP Spray Gun

    • 3M™ Accuspray™ Pressurised HGP Spray Gun and 3M™ PPS™ Pressure Cups are designed for the easy application of high viscosity coatings such as underbody protection, high build primers and stonechip. With the ability to control thickness and finish, the system allows for minimal waste in product and time, making it both efficient and effective - and additionally, any cleaning work is reduced to a minimum.

      The 3M™ Accuspray™ atomising heads / nozzles, pressure and material flow, allows for different textured coatings to be applied, meaning you can easily match several different OEM textures to get the finish you need. The 3M™ PPS™ Pressure Cup takes air vented from the spray gun and pressurises it to ensure high viscosity material can be sprayed evenly. Pressurising the pot helps the bag to collapse and release the material in the required texture with the 3M™ Accuspray™ Pressurised HGP Spray Gun and 3M™ PPS™ Pressure Cups.

      Click the play button in the image to watch the video

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Benefits of using 3M™ Accuspray™ Pressurised HGP Spray Gun for protective coatings.

  • Stone-chip protective coating
    Reduce spray time to boost productivity
    • No repeat layering of coating - just select the right setting.
    • Achieve the required finish quickly, reducing the application time and allowing more jobs to be completed.
    • Quick and easy cleaning, thanks to the easily removable and disposable nozzle.
  • Accuspray HGP in use
    Reduce costs by minimising waste
    • The 3M™ Accuspray™ HGP provides greater control for the application of coatings versus the conventional Schutz style gun, therefore reducing material waste.
    • Minimal overspray.
    • Less solvent is needed to clean up, thanks to disposable, removable parts (nozzle and liner).
  • 3M Accuspray Gun
    Improve finish
    • Fluid control allows you to select the texture and thickness you want.
    • The gun design and pressurised pot aids complete and even coverage.
    • Controllable spray pattern.
    • Paintable stonechip (we recommend the stonechip coatings to be primed prior to basecoat application).

    Please always consult national regulations for suitable Personal Protective Equipment (PPE) for use against hazards, including isocyanates. PPE shown may not be adequate or suitable for your specific application or substances used.

Stone chip and underbody protection products

Discover our range of stone chip and underbody protection products to help achieve high quality, efficient repairs in your bodyshop.

How to set-up the 3M™ Accuspray™ HGP gun

Step-by-step process guide to get set-up and ready to apply your protective coatings

  • Attaching air regulator to the Accuspray gun

    Step 1 - Attach the air regulator

  • Attaching nozzle to the Accuspray gun

    Step 2 - Attach the nozzle

    • Choose your 3M™ Accuspray Atomising Head / Nozzle based on the finish you want to achieve.

      • 1.4mm Atomising Head / Nozzle for Flat / Fine Coatings.
      • 1.8mm Atomising Head / Nozzle for Flat and Medium Textured Coatings.
      • 2.0mm Atomising Head / Nozzle for Medium and Heavy Textured Coatings.

      Pull the trigger back on the gun and hold. Put the nozzle in place and ensure the release buttons are aligned with the latch openings. The double click signals that the nozzle is fully engaged.

      Recommended products:

      3M™ Accuspray™ nozzles

  • Attaching pressure cup to the Accuspray gun

    Step 3 - Prepare and attach the pressure cup

    • Place the 3M™ PPS™ liner in the 3M™ PPS™ pressure cup and pour the required amount of coating into the liner. Once the liner is filled, pull the filter tab and remove it from the 3M™ PPS™ lid. Attach the lid to the liner and push it into place to ensure it’s secure. Screw the black 3M™ PPS™ collar onto the 3M™ PPS™ pressure cup.

      Recommended products:

      3M™ PPS™ Pressure Cups

      3M™ PPS™ Lids & Liners

  • Connecting the flexible tube to the Accuspray gun

    Step 4 - Connect the flexible tube

    Connect the flexible tube to the 3M™ Accuspray™ HGP gun body side and then connect the air line to the regulator. Set the air pressure to 20 psi (1.4 bar) when the trigger is pulled and adjust the fan control from closed to open by making a 1/4 to 1/2 turn. The gun is now ready to use.

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How to get the texture that you want?

The 3M™ Accuspray™ Pressurised HGP Spray Gun offers outstanding control over texture build. Choose the nozzle size and adjust the gun settings to get the texture you want.

  • Accuspray nozzles
    Nozzle size
    • 1.4mm : Light textures - thinner liquids
    • 1.8mm : Medium textures
    • 2.0mm : Heavy textures - higher viscosities
  • Adjusting fluid control on Accuspray gun
    Fluid control

    With each 1/4 turn, you change the fluid volume and material output - thus the structure achieved.

How to clean the 3M™ Accuspray™ HGP gun

Step-by-step process guide to clean your 3M™ Accuspray™ gun for continued high performance for your protective coating applications

  • Disconnecting air line from Accuspray gun

    Step 1

    Disconnect the air line, pull back the trigger and release the fluid back into the cup.

  • Remove air line and PPS cup

    Step 2

    Remove the air line and the 3M™ PPS™ Cup. If required, use the sealing cap to store for further use.

  • Flush out Accuspray nozzle

    Step 3

    With an appropriate solvent (or water for Waterbased Coatings), flush out the 3M™ Accuspray™ atomising head / nozzle so it is clear of coating.

  • Detaching nozzle from Accuspray Gun

    Step 4

    Once you’re satisfied that the nozzle is completely clean, pull the trigger back and take the nozzle straight out from the gun body. Remove the nozzle in this way to avoid bending the fluid needle.

    Wipe the needle clean and inspect the nozzle for damage. If the nozzle is broken or worn, please dispose and use a new nozzle. If the nozzle is fine, it can be reattached and used on your next application.

    Keeping the 3M™ Accuspray™ Pressurised HGP Spray Gun clean is important to ensure its longevity and continued high performance.

Technical tips for repairing stone chip and underbody protective coating

Here are some valuable insights into specific challenges surrounding repairing stone chip and underbody protective coating, including quick tips on preventing common issues such as....

  • Customer Challenge:

    It´s difficult to match the finer textures, which are found on modern vehicles. Repeated layering of coating to get a final and fine textures is akward and often does not lead to the desired result.

    Technical Tip:

    A light texture can be achieved by using the different smaller sized 3M™ Accuspray™ Atomising heads 1.8 mm or 1.4mm at recommended 1.4 bar spray pressure. 1/2 turn on fan control, 3/4 turn on fluid control and you can spray at any angle, achieving very fine patterns.

  • Customer Challenge:

    In order to achieve the different textures on a vehicle or gradually changing textures on one panel, users often need several work steps and sometimes an additional intermediate sanding.

    Technical Tip:

    The 3M™ Accuspray™ HGP provides greater control for the application of stone chip and underbody coatings versus the conventional Schutz style gun. You only have to mask the areas and change the settings of the gun step by step in order to achieve a gradually finer texture. With fluid control and controllable spray pattern, it is possible now to achieve the different textures in one working step.

  • Customer Challenge:

    In a bodyshop, there are regularly a range of highly viscous materials like stone chip coatings, underbody coatings or sprayable body fillers, all requiring each their individual application tool. Besides challenging application conditions, these tools are also time consuming to clean.

    Technical Tip:

    Due to the high material transfer rate through the pressure cup system, you can work with a large range of high viscosity materials and usually just 1 gun for all applications: sprayable body filler, stone chip coatins or underbody protection materials.

    Start with a small nozzle size for finer textures - from small (1.4 mm nozzle) to large (2.0 mm nozzle). The desired pattern can be created by taking advantage of the gun technology (vary nozzle size and / or settings of the fan pattern). Any material should always be processed at room temperature.

Discover more from 3M

  • Haven't found what you're looking for? Or perhaps you would like to arrange a demonstration? Click here to get in touch!

  • Remember to always select appropriate Personal Protective Equipment - Eyewear, gloves, hearing and respiratory protection for your job and workplace!

  • We don't just have solutions for protective coatings. See our extensive range of solutions for all your car repair needs!

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