SEM High-Build Primer Surfacer - 20oz Aerosol Can - White
SEM High-Build Primer Surfacer - 20oz Aerosol Can - White

SEM High-Build Primer Surfacer - 20oz Aerosol Can - White MPN - 42043

$36.31
$39.94
$36.31

MPN : 42043

SKU: 109318
Availability: In stock
Product type: Automotive/RV | Accessories,Boat Outfitting | Adhesives/Sealants/Tapes
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Subtotal: $36.31
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White primer-surfacer finish
For supported rigid / flexible substrates
Sandable acrylic filling layer
SEM High-Build Primer Surfacer - 20oz Aerosol Can - White

SEM High-Build Primer Surfacer - 20oz Aerosol Can - White MPN - 42043

$39.94 $36.31
SEM High-Build Primer Surfacer - 20oz Aerosol Can - White

SEM High-Build Primer Surfacer - 20oz Aerosol Can - White MPN - 42043

$39.94 $36.31

    SEM 42043 High-Build Primer Surfacer White 20 oz Aerosol, MPN 42043 and Mariners Warehouse SKU 109318, supplies sandable flexible acrylic priming and surfacing. Build a sandable white primer layer on documented suitable metal, plastic or composite surfaces. Match the material-specific cleaning and adhesion-promoter requirements before applying this flexible acrylic surfacer.

    42043 supplies the white version of SEM’s flexible acrylic High-Build Primer Surfacer. It provides a sandable priming/filling layer for supported rigid or flexible repair surfaces and accepts most refinish materials under a compatibility check. SEM lists steel, aluminum, plastics, SMC and fiberglass; urethane is included in its application description. Actual plastic type and surface condition determine preparation. Color selection does not turn the product into a rust converter, structural filler, self-etching primer or final color coat.

    For metal/aluminum, clean with SEM Solve, sand with 180–320 grit and re-clean as directed. For plastic, follow SEM’s Scuff & Clean/water-rinse and Plastic & Leather Prep or XXX Universal Surface Cleaner sequence, sand with 180–320 grit and re-clean; the TDS specifies XXX Adhesion Promoter for olefin-based plastics. For SMC/fiberglass, use the specified compatible cleaner without saturating exposed fibers, sand with 180–320 grit and re-clean. Mask the surrounding area, shake and apply under the actual label conditions. Use 2–3 medium coats with 5–10 minutes flash between coats. The TDS lists a 1-hour dry reference and 320–400-grit sanding for the applied primer; verify actual readiness and the following refinish system before proceeding. Coverage reference is 11 square feet per can at 2 mil dry-film thickness, with real usage affected by shape, overspray and film build. Clear the spray tip as directed and follow the current label/SDS for ventilation, protection, ignition control and storage.

    Clear Product Details

    Review the 16 oz gel format, specifications and application directions.

    Surface Guidance

    Check fiberglass, gelcoat and finish suitability before use.

    Product Support

    Ask about your surface and stain type before ordering.

    Shipping & Returns

    Review shipping information and return conditions before purchase.

    Application Guides

    Match the Repair Material to the Substrate and System

    Check 42043 by its actual factory-finish, sanding-guide, primer-surfacer or clearcoat role. Confirm substrate, coating compatibility, color or sheen, preparation, application and package before choosing.

    1. Identify a Primer-Surfacing Task

      Choose a sandable filling/priming layer for a documented suitable repair. A sanding guide, structural filler and final clearcoat serve other steps.

    2. Match the Material and Preparation

      Check steel, aluminum, exact plastic, SMC or fiberglass against the TDS. Olefin-based plastic requires the specified adhesion-promoter step; exposed composite fibers must not be saturated.

    3. Choose the Primer Color

      42043 is white. The family also includes black 42003, gray 42013, beige 42023, rose 42033 and white 42043. Match the following refinish process rather than an assumed vehicle paint-code match.

    4. Follow the Substrate-Specific Sequence

      For metal/aluminum, clean with SEM Solve, sand with 180–320 grit and re-clean as directed. For plastic, follow SEM’s Scuff & Clean/water-rinse and Plastic & Leather Prep or XXX Universal Surface Cleaner sequence, sand with 180–320 grit and re-clean; the TDS specifies XXX Adhesion Promoter for olefin-based plastics. For SMC/fiberglass, use the specified compatible cleaner without saturating exposed fibers, sand with 180–320 grit and re-clean.

    5. Apply, Dry and Sand as Directed

      Apply 2–3 medium coats with 5–10 minutes flash; use the 1-hour dry reference and 320–400-grit sanding instructions while checking actual readiness.

    6. Plan Coverage and Separate Supplies

      The 11 sq ft per can reference assumes 2 mil dry-film thickness; actual usage varies. One white SEM 42043 High-Build Primer Surfacer aerosol in the manufacturer-listed 20-ounce container format. Read the can for net contents. This is one can, not a 12-can case. Cleaners, abrasives, any substrate-required adhesion promoter and following refinish coatings are separate.

    Choose the High-Build Primer-Surfacer Color

    SEM 42043 supplies white High-Build Primer Surfacer. The separately sold family colors are black 42003, gray 42013, beige 42023, rose 42033 and white 42043, each in the listed 20-ounce aerosol-container format. Select the shade for the prescribed refinish system; the product is a primer layer rather than a vehicle-specific final paint color.

    Color changes do not remove the material-specific cleaning, sanding or olefin-plastic adhesion-promoter requirement. Keep the same coat, flash and readiness checks, and confirm compatibility with the following paint system before choosing an alternative color. Review the SEM 42013 High-Build Primer Surfacer Gray 20 oz Aerosol as a separately sold option.

    Continue Your Repair, Sealants & Trim Selection

    Choose by the actual repair function, substrate, profile and application instructions, then compare exact package contents.

    1. Compare Repair, Sealants & Trim

      Compare replacement seals, edge trim and repair products by their own documented role, dimensions and installation requirements.

      Browse Repair, Sealants & Trim

    2. Explore Wash & Surface Care

      Review cleaning products for a separate surface-care task. Check the exact material and label; category placement does not establish adhesive-preparation compatibility.

      Browse Wash & Surface Care

    3. Explore Automotive & RV Accessories

      Return to the parent collection for another maintenance or replacement task. Check every item’s own requirements.

      Browse Automotive/RV

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    Frequently Asked Questions

    What does SKU 109318 include?
    One white SEM 42043 High-Build Primer Surfacer aerosol in the manufacturer-listed 20-ounce container format. Read the can for net contents. This is one can, not a 12-can case. Cleaners, abrasives, any substrate-required adhesion promoter and following refinish coatings are separate.
    Which color and quantity are supplied?
    One white aerosol under MPN 42043, in the manufacturer-listed 20-ounce container format. Check the can for net contents; this is not a case.
    Which materials does the manufacturer name?
    Steel, aluminum, plastic, SMC and fiberglass, with urethane included in the description. Use the exact material-specific preparation; a general plastics reference does not establish every untreated plastic surface.
    Does plastic need an adhesion promoter?
    The TDS specifies XXX Adhesion Promoter for olefin-based plastics after its cleaning and sanding procedure. Verify the actual plastic and promoter instructions; the promoter is separate.
    What sanding grits are specified?
    The substrate preparation uses 180–320 grit in the TDS’s material-specific sequence. The applied primer is sanded with 320–400 grit after appropriate drying.
    How many coats and how long between coats?
    The TDS gives 2–3 medium coats, 5–10 minutes flash between coats and a 1-hour dry reference. Check actual readiness and the next coating’s requirements before sanding/refinishing.
    Is 11 square feet a guaranteed area?
    No. The reference is 11 square feet per can at 2 mil dry-film thickness. Surface shape, spray technique, overspray and film build affect the usable area.
    How can I confirm the right selection?
    Contact Mariners Warehouse with SKU 109318, MPN 42043, your exact product MPN, component or substrate material, existing coating, application method, working conditions and required package size.

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