Bondo® Glass Reinforced Filler

Fiberglass Quality without the Extra Work
Bondo® Glass Reinforced Filler provides fiberglass-quality repair of small holes and rust-outs (up to 1/2") without the need for backing strips, fiberglass mat or fiberglass resin. This reinforced body filler contains short, interlocking fiberglass strands, making it twice as strong as standard body filler and much easier to use during vertical repairs. If your repair needs even more strength, it also works well with traditional fiberglass repair materials and tools.

Easy from Mixing to Sanding
The filler is easily mixed using the included Bondo® Red Cream Hardener, designed specifically for use with Bondo® fillers. It also features a fast-drying formula that is sandable in as little as 20 minutes, saving you time on auto body repairs.

For Auto or Marine
This waterproof filler is ideal for repairing dime size or smaller (up to 1/2") rusted-out metal holes and shattered fiberglass body parts. It is compatible with all paint systems for cars and boats.

Bondo® Short Strand Fiberglass Reinforced Filler instructions:
Step 1: Clean all surfaces with soap and water followed by a low VOC compliant cleaner. Allow to dry.

Step 2: Sand the damaged area with 80 grit sandpaper or a 36 grit disc. Cut damaged or cracked pieces of fiberglass away with a saw blade. Sand the area 1” beyond the repair to roughen the surface. Clean again with a low VOC compliant cleaner.

Step 3: Stir the filler before using.  Knead the hardener tube. For a 3-inch diameter puddle of filler, squeeze out a 3” long strip of hardener.  This is the maximum recommended amount to mix at any given time for optimal application. Mix thoroughly to a uniform color on a clean, non-porous surface. When product is mixed, the working time is 3-4 minutes. Do not add hardener directly into the filler container.

Step 4: Spread an initial thin layer of the mixed filler over the repair area using firm pressure to ensure maximum adhesion. Apply additional filler as needed. Allow filler to cure 30 minutes. 

Step 5: Rough shape the filler with 80 grit sandpaper. Open any soft spots, dry fiber pits or pinholes with a sharp knife and clean the area with a cloth. Apply filler to any large voids. Finish sand with 180 grit and finer. Featheredge the repair.  Wait 45 minutes and apply 2-3 coats of primer to cover the repair area.

Step 6: Apply Bondo® Glazing and Spot Putty to fill in small imperfections and re-prime with 2-3 coats. Follow paint manufacturer’s recommendation for priming and final finishing.

For best results apply at 45°F (7°C) or above. Do not put mixed filler back in the can. Clean tools with acetone or lacquer thinner. Help line: 1-800-494-3552       

About the 3M™ Body Repair System
Even a small repair can seem complex at first. So 3M's Body Repair System simplifies the entire automotive body repair process by dividing it into four stages:

• Stage 1 — Prepare. This stage includes pulling dents, removal of paint and rust and efficient, effective masking of the area.
• Stage 2 — Fill. This stage involves patching holes with reinforced filler and smoothing and shaping filler before painting.
• Stage 3 — Paint. This stage includes painting the area and blending and smoothing primer and paint.
• Stage 4 — Finish. The final stage for showroom-grade results: removing small defects, sealing and polishing clear coats and other painted surfaces.

3M supplies premium products such as abrasives, tapes, body fillers and tools for every stage. This system helps you work easily, efficiently and successfully across the entire body repair process.

Bringing Science to the Art of Auto Body Repair
As a brand of 3M™, Bondo® is well known among collision repair professionals and others who are committed to helping you restore the beauty and value to your cars and boats. This fiberglass reinforced filler is another way that 3M applies science to life — and helps you rediscover the excitement of the vehicles you own.

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