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How to fix a crack in a fiberglass tub?

Fiberglass tubs and showers are a sturdy and long-lasting alternative to classic ceramic or metal tubs and showers. Inadequately supported tubs and those subjected to heavy usage and abuse can develop ugly fractures over time. A basic fiberglass repair kit enables you to patch these fractures before they become greater problems down the road.

How to fix a crack in a fiberglass tub?

1. Ensure that the area surrounding it is dry and clean

Clean the crack area using a cloth or sponge dipped in a home cleanser. If left untreated, these hairline fractures can grow into broader or deeper breaches in the tub’s floor. After cleaning and drying the cracked area, sand it using fine-grit sandpaper.

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2. Sand the crack’s surrounding region

After cleaning and drying the cracked area, sand it using fine-grit sandpaper.  Sand the surface once again before applying an adhesive. After which, we apply an epoxy mixture and a piece of fiberglass fabric.

3. Apply the plaster when it has been prepared

An adhesive or bonding agent will be included in the fiberglass tub repair kit. It also includes instructions for getting ready. First, put it together according to the instructions, then place it in the crack and surrounding sand. This may be done with either the supplied brush or your own paintbrush. After that, apply an adhesive and then a fiberglass filler to the crack.

4. Fiberglass filler should be used to fill the crack

Bondo Glass Reinforced Filler

Take the fiberglass filler from the fiberglass tub repair kit when the glue has cured. Later, use a putty knife to apply it to the hairline crack on the tub. Remove any excess filler around the crack’s edge. Allow for thorough drying of the filler before proceeding. Sand the area surrounding the break once again.

5. Sand the area around again

Using sandpaper or emery cloth, sand the area surrounding the crack. Remove it from the earth once it has been leveled with the surrounding area. Don’t overdo it, or the results of your fiberglass tub crack repair may be ruined. Once more, sand the area around the break.

6. Apply epoxy to the fracture

Clear Table Top Epoxy Resin That Self Levels

Apply more epoxy mixture, followed by a sealer, to fix a hairline fracture in a fiberglass tub. To make the needed epoxy mixture, follow the epoxy or polyester resin guidelines. A fiberglass repair kit is included. Using a brush, apply the epoxy mixture to the crack and surrounding area. For best results, the epoxy mixture should extend at least 2 inches beyond the crack.

7. Include fiberglass cloth

Using a tiny piece of fiberglass fabric, cut a small hole in it (included in the fiberglass repair kit). Make sure it’ll work in the region where you’ll be applying the epoxy mixture. Before the epoxy hardens, wrap the opening with a cloth. Firmly press it into the epoxy mixture. Remove any air bubbles that have developed beneath the fabric using a putty knife.

8. Use a second epoxy mixture

Using the paintbrush, apply the remaining epoxy mixture on and around the fiberglass cloths.

Apply a generous but acceptable coating of the epoxy mixture at this point.

Applying a sealant is the next step (also included in the fiberglass repair kit).

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The sealer protects the crack-sealing ingredients from water and other contaminants.

9. Use a sealant

Applying a sealant is the next step (also included in the fiberglass repair kit). The sealer protects the crack-sealing ingredients from water and other contaminants.

After the sealant has dried, you’re free to use your bathtub again.

Use a polishing compound to restore the shiny appearance of your fiberglass bathtub before using it again. This method for repairing a crack in a fiberglass tub applies to all cracks in the tub.

It also explains how to fix fractures in the bottom of a fiberglass bathtub and replace a broken tub surround.

Also, Read – Will flex seal fix a cracked bathtub?

What causes a fiberglass tub to crack?

What causes a fiberglass tub to crack?

If you’re wondering why your bathtub is breaking, consider the following reasons for cracks in fiberglass tubs:

1. Natural aging

The bathtub will wear out over time due to everyday use. The tub’s surface will gradually deteriorate, causing the tub to become thin enough for cracks to form.

2. Inadequate assistance

Fiberglass bathtubs might develop cracks when installed on uneven terrain. This is because the user’s weight is not distributed equally.

3. Use of abrasive cleansers

Some aggressive cleaners, such as bleach and acidic cleansers, can gradually erode the surface of the fiberglass bathtub, making it thinner and more prone to splitting under pressure.

4. Dropping and slamming large things against it

The impacts will damage the bathtub’s surface in both circumstances and need thorough repair. In addition, since fiberglass is one of the lightest types of bathtubs, it is simple to transport and has a higher chance of being dropped.

The depth of the break decides whether or not you should attempt to repair it yourself. You can accomplish anything by yourself if it is only on the surface. However, if the crack extends to the opposite side of the bathtub, you’ll need to call a plumber.

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How to Avoid Cracks in a Fiberglass Tub?

Tub cracks may be avoided by performing the following:

  • Ascertain that the bathtub is adequately supported and situated on level ground.
  • Avoid using strong cleaners to clean the tub.
  • Use the prescribed cleansers instead, or even mild home cleaners.
  • Avoid dropping the bathtub or striking it with heavy items.
  • Rinse it after each usage to avoid harsh chemicals accumulating on the tub’s surface.
  • If the bathtub already has a crack, drill little ¼ inches stop-drill holes at the ends of the fractures. This will prevent them from growing further, then repair it as indicated above.
  • Protect the bathtub from any abuse, and you’ll seldom find cracks. If it has too many cracks, get it polished to restore its appearance and integrity.

Wrapping Up

Fiberglass is recognized for its durability, and it is unquestionably superior to metal and ceramic. As a result, most homeowners choose tubs constructed of this material. Unfortunately, Flex Seal cannot repair a damaged bathtub since it has no intrinsic value.

While Flex Seal can halt a leak, it cannot repair a break. This is because the crack continues to expand beneath the Flex Seal layer. However, if the tub has insufficient support or is subjected to common misuse, you will discover fractures on its surface sooner or later. If they are not fixed or treated right away, they will develop larger and deeper, causing total damage to the fixture. Fortunately, hairline fractures in a fiberglass tub are relatively simple to fix.

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