Moving on with the wooden tank, the next step is to apply the fiberglass strips along the seams of the tank. These strips will effectively strengthen the seams and allow just a little more movement in the joint than the structure or coating would normally be able to withstand.
We use 1.5 ounce fiberglass chopped strand matt, not woven fiberglass in this video. You can use woven fiberglass but you should cut the strips at a 45 degree angle so that the weave of the fiberglass crisscrosses over the seam you are trying to cover. Chopped strand matt will allow stress to be dissipated in a variety of directions when it occurs. Woven fiberglass will always have at least one weave following the same direction of the joint and thereby act as a weak spot.
The key to fiberglass is saturation. If you take anything away from this particular video, remember that one fact. It will mean the difference between a good, solid structure and weak spots. If you saturate the fiberglass, there will be no air pockets and air pockets within or under the fiberglass mean weakness.
Only work with fiberglass cut into sizes that you are comfortable working with at any given time. It is not necessary to lay the fiberglass down in one continuous strip. You can overlap pieces by 1/2 inch as you go.