How to Use Bondo
- 1). Clean the area where you will be applying the Bondo. A clean surface is vital to a solid patch.
- 2). Place a bit of Bondo in your paint pan. You need to work with Bondo in small batches, so a 2-inch section of Bondo is plenty.
- 3). Open your hardener and put a strip across the top of your Bondo. Mix them together very well. Proper mixing is essential to getting the Bondo to harden up.
- 4). Scoop the mixture up with your putty knife and apply it to your surface. You need to work fast as the Bondo will harden quickly.
- 5). Fill in your surface completely, spreading the Bondo as evenly as possible. Be sure to fill in your edges well to keep any moisture from seeping under your Bondo.
- 6). Allow your Bondo to harden for approximately 45 minutes. This should be plenty of time for it to harden completely. If it is still soft after an hour, you did not add enough hardener to the mixture.
- 7). Sand your Bondo with medium grit sandpaper. Wear a face mask as you do not want to inhale particles of the Bondo. Run the sandpaper over the entire surface of your Bondo to even out the big ridges in your surface as much as possible.
- 8). Change your sandpaper to fine grit and finish sanding your surface. Run your hands over the surface as you sand to make sure you get a perfectly even surface.
- 9). Wipe your surface clean with a damp towel. You want to remove all traces of Bondo particles from your surface before you attempt to paint it.
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