The way to correct a Crack in a Fiberglass Hot Tub
A dip in the spa might help relieve the stress that builds during the afternoon, but a small crack in the surface of your fiberglass spa can allow the water to slowly seep from the bathtub and reduce its enjoyment valve. Over time, a small crack can increase in size and cause irreparable damage. Fixing a crack in the fiberglass can stop the crack from propagating and expand the life of your spa.
Drain the spa to expose the crack in the fiberglass. Switch off the breaker to the spa.
Protect your hands using vinyl gloves, and your eyes with goggles. Wear a respirator to avoid breathing in metallic dust and some other fumes emitted by the repair merchandise.
Install a 1/16-inch drill bit into a cordless drill. Drill a small hole through the fiberglass at the tip of the crack where it starts, and drill a second hole at the tip of the crack where it finishes to keep the crack from propagating.
Insert a grinding bit into a cordless rotary drill. Use the tool to make a “V” shape in the fiberglass along the crack, increasing the split thickness to at least 1/16 inch, but no deeper than 3/16 inch.
Wipe the surface of the spa across the crack with a soft cloth or paper towel. Sand the fiberglass tub’s surface using 400-grit sandpaper to smooth the region around the crack.
Put a little bit of acetone on a soft cloth. Wipe the prepared crack with the acetone to remove any debris and dust from the grinding and sanding.
Pour the glue and activator from a fiberglass tub repair kit into a small disposable container. Use the correct quantity of repair products indicated by the manufacturer, and mix them together using a wooden craft stick.
Apply the mixture to the crack using a clean craft rod. Use the rod to push the repair merchandise into the crack, slightly overfilling the crack to allow for shrinkage.
Allow the repair merchandise to dry for a minumum of one hour or so until the item becomes hard to the touch. Sand the dried product with 400-grit sandpaper to smooth the dried product.
Apply the rubbing compound which comes with the repair kit to the sanded surface of the spa. Use a buffing pad to buff and shine the surface of the spa.