When you're preparing to cut a fiberglass tub surround, there are a few important things that you'll need to keep in mind in order to make sure that the procedure goes smoothly.
Step 1 - Measure and Mark the Tub Surround
Measure out the borders of the tub into the fiberglass surround material. Be sure to leave a small extra space in between the tub and the fiberglass for insulation and other materials to go (approximately 1/2 of a centimeter on each side). Mark out the dimensions of the tub on the fiberglass using a pencil or pen.
Step 2 - Cut the Tub Surround
Using a vice or another device to hold the fiberglass surround in place, use your saw to cut out the tub surround. You'll be able to get rid of the piece of fiberglass in the middle or to use it for another project.
Step 3 - Finishing Up
Be sure to sand down the edges of the surround in order to avoid damaging the tub itself when you install it. If you have any other questions, speak with a professional.