Sand and Prepare the Surface of a Resin Bumper

Why Sanding is Essential

Sanding allows you to remove any uneven areas, scratches, or remnants of old paint on your resin bumper. This creates a slightly roughened texture, which is crucial for new fillers or resins to adhere effectively. Skipping this step can lead to poor bonding, affecting both appearance and durability.

How to Prepare a Resin Bumper for Repair

• Begin by washing the bumper to remove dirt, grease, and debris.
• Once dry, use medium-grit sandpaper (typically 120–180 grit) to sand damaged or uneven areas until smooth.
• For deep dents or cracks, consider applying a reinforced filler such as CROP 2K Fiberglass Putty after sanding. Its fibreglass-reinforced formula is easy to sand and resilient after curing.
• Finish with a finer grit (up to 320 grit) for a smooth, paint-ready finish.
• Wipe down the area with a clean, lint-free cloth to remove dust.

When Surface Preparation Matters Most

If your resin bumper has substantial cracks, holes, or previous repair attempts, thorough surface preparation is vital. Only a well-prepared area ensures that new repairs, such as fibreglass putty or epoxy coatings, will bond firmly and evenly.