FIBERGLASSING A BOAT Frank is tired of leaky boats and wants to fiberglass his new one, but he does't know how much resin to purchase. The folks at the fiberglass place said one gallon will do 200 square feet on layers of resin that wet the cloth. With following coats of clear resin, one gallon will cover 350 square feet. He wants do one layer of cloth, with two coats of clear resin over the cloth. First he had to find the area of his boat. His boat is 18' long and 4' wide at the widest part.

This boat is covered with fiberglass from bow to stern and painted to protect from ultraviolet rays of the sun. It has a sheet of UHMW plastic in the front to protect from rocks.

He figured the front was like a triangle.

The sides and transom are 24" high.

He tried to figured the surface area of his boat. He knew he could round off many numbers as he knew he couldn't buy .3245 of a gallon. He only wanted the approximate area.

 

Figure it for him. Feel free to round off numbers.

1) Area of bottom =
2) Area of sides=
3) Area of stern=

Total___________

Now, figure how many gallons of resin required for the first coat that covers the fiberglass cloth at 200 square feet per gallon. ______________

Now, figure how many gallons of resin for the second and third coats that go over the cloth at 350 square feet per gallon.________________

Add the two together and get total gallons. _________________

Turning all that into dollars.

If resin is $18 a gallon and cloth is $1.50 a square foot, how much will it cost him to fiberglass his boat, with one layer of resin/cloth, and two layers of resin on top?

 

 

 

Note: There are two types of resin: poly resin and epoxy. Each has it's advantages. Poly resin is much cheaper to purchase and mix. However, it has a terrible smell, and can only be used in a well ventilated place. It also has a short shelf life, about 6 months.

Epoxy resin is much stronger, has a limitless shelf life, and can be applied indoors with no harmful odors. It is considerably more expensive.

This problem was set up with figures for poly resin.

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