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How to Fix Hairline Crack in Plastic Tub

How to Fix Hairline Crack in Plastic Tub

A bathtub is like a warm hug after a long, tiring day—luxurious suds, calming water, and ambient music to tie it all together. Just like you, though, your bathtub, especially if it’s made of plastic, also goes through wear and tear. K2 Plumbing, a top plumber in Hollywood, FL explains that it is common for cracks to form. When this happens, remember to not hastily throw it away; instead, just give back some much-needed TLC.

3 Common Causes of Cracks in Bathtubs

Major bathtub cracks usually start out as small ones that have gone unnoticed for a significant amount of time. Once a small crack appears, water and moisture tend to seep into the tub’s internal structure, which results in the disintegration of the material. According to Badeloft Luxury Bathrooms, the common causes of bathtub cracks are much simpler than you would expect:

  • Lack of support – Bathtubs without much structural support tend to get bogged down, which, over time, leads to deformation. Once the structural integrity, even if flexible, is compromised, cracks start to manifest. 
  • Heavy objects – Heavy objects that fall on your bathtub cause dents and small holes that eventually lead to big cracks.
  • Abrasive cleaners – Heavy cleaners with abrasive properties such as bleach and strong detergents cause your bathtub’s enamel to chip off. When this happens, moisture finds its way inside, making the tub susceptible to cracks and other forms of damage.

How to Fix Hairline Crack in Plastic Tub

Fortunately, hairline cracks in plastic bathtubs are fairly easy to fix, and so long as you do not let the crack languish for a tremendous amount of time, you’ll find yourself luxuriously relaxing soon enough. Parenting website recommends this easy procedure to fix your tub’s hairline crack:

Tools and materials to prepare:

  • Power drill               
  • ¼-inch drill bit
  • Hairdryer (optional)
  • Putty knife
  • Rag
  • Nylon-bristled paintbrush
  • 120-grit sandpaper
  • 240-grit wet/dry sandpaper
  • Epoxy resin

Gel coat enamel

  1. Clean your plastic bathtub as you normally would, and let dry for 24 hours. Inspect closely for cracks and other forms of damage. Locate and mark the crack/s to spot easily.
  2. Once you have located the crack/s, drill a ¼-inch hole on each side of each crack.          
  3. Gently sand the crack using 120-grit sandpaper. Do not sand abrasively as this would further damage the plastic tub.
  4. Clean the sanded area with a damp rag, making sure to remove sand particles and other debris. Let the area dry for 12 hours, or if you’re pressed for time, dry with a hairdryer. This step is important as the epoxy resin would not adhere to a wet surface.
  5. Following package directions, prepare the epoxy resin, and fill the hairline crack with mixed putty. Level the surface, and scrape off excess resin using the putty knife. Leave the epoxy resin to cure for at least 12 hours.
  6. Sand dry the cured area with 240-grit wet/dry sandpaper. Wet the sandpaper, and sand the crack once more.
  7. Once again, clean the sanded area with a damp rag, and let it dry for another 12 hours.
  8. Finish off the repair with a light layer of gel coat enamel, and let it dry thoroughly for at least 4 hours before using again.

How to Care for Your Plastic Bathtub

As you turn to your bathtub for pampering, keep in mind to pay it back with ample care. Here are some ways to care for your bathtub:

  1. Keep heavy objects away – If you must decorate the area around your bathtub, make it a point to secure heavy objects so they do not fall into the tub. 
  2. Use gentle bathroom cleaners – Protect your bathtub’s protective enamel from eroding by using only mild bathroom cleaners. You can even opt to use natural, non-toxic ingredients such as lemon, vinegar, baking soda, salt, and essential oils.
  3. Clean your bathtub once a week. This prevents any residual soap, gels, and other substances from building up on your tub’s surface.

What to Do When Your Plastic Bathtub Is Beyond Salvage

Is your cracked plastic tub beyond repair? Don’t make a trip to the junk shop just yet! Thanks to hobby websites such as Pinterest, upcycling old and irreparable bathtubs has become both easy and trendy. Architecture Art Designs rounded up the Internet for clever upcycled bathtub ideas:

  • Garden pot – You can plant your favorite herbs or flowers—heck, even an adorable lemon tree!
  • Cheerful sofa – Paint it a cheery color, plop down a comfy cushion, throw in some pillows—et voila—a comfy conversation starter.
  • Outdoor swing – Just like the sofa but with rocking feet!
  • Three-part chairs – Cut your bathtub into three pieces, and you get yourself two chairs with a backrest and one without—either way, it would look sleek and modern.
  • Cooler – The next time you throw a party, load all your beverages into the bathtub, go crazy with ice, and let your guests pick an ice-cold drink of their choosing.