How to Fill Bathtub Cracks With Bondo
- 1). Allow the bath tub and the cracked area to completely air dry over night before you proceed. Sand the damage area so the it is smooth.
- 2). Apply Bondo to the crack(s) in the tube. Make sure that the cracks are completely filled. Use a putty knife to spread the Bondo so that it is flush.
- 3). Allow the Bondo to completely dry for 24 hours. Make sure that no one uses the tub or gets the Bondo wet. Sand the Bondo until it is smooth and flush with the tub.
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