Fiberglass Floor Repair

Mark,

DavidF gave me a great procedure to follow to replace the "broken" spot that I have on my floor. My problem seems to be the same as yours. Allow me to copy and paste from his email:

"Simply cut out the damaged fiberglass area. Purchase the pourable foam (high density) from US composites and build the foam back up to the original level. The foam can be cut and then sanded flat to just below final floor level. Then, using alternating layers of fiberglass mat (epoxy mat) and woven roving repair the floor. Here are the steps:

1. Peel back carpet and protect.
2. Cut out damaged floor section. I use an air powered cut off disc.
3. Repair foam to level with bottom of fiberglass floor.
4. Grind the cut edges of surrounding floor to a 12:1 taper all around. What this means is that if the floor is 1/4" thick, then your taper should be 3" wide (from knife edge to full thickness).
5. Starting with mat and ending with mat, cut alternating layers of fiberglass to "walk" up the taper. The first layer should be just larger than the hole and the last layer should cover the taper fully. I usually just make each successive layer about 1/2" larger all around. If the end thickness is not enough, I just fill in with cloth and mat until it is relatively flat (no low spots). You should end with no fewer then about 7 alternating layers. You need to wet out the fiberglass cloth or mat well before installing. Then after every two layers, roll out the air bubbles and compress the layers. Purchase a grooved roller (flat) from US Composites. Make sure the composite is well saturated with no air or voids. Avoid pressing too hard with the roller or you will squeeze out all the resin and never get out the air.
6. Once the composite has fully cured, grind it flat and even with the surrounding floor. If you find a small low spot or two, leave it as the carpet will make it virtually un-noticeable. You will note that the floor is not very flat from the factory when you pull up the carpet."

Thanks again David for the great tips!

I havent done the repair yet (soon though!). I consulted US Composites to get their recommendation on materials and this is what I got:

FOAM-0816     2 cu. ft. of 8 lb density urethane foam
FG-EM10550     1.5oz Epoxy Mat, 50" width
FG-C0630S     4 oz E-Glass cloth, 38" width
EPOX-635314     635 Thin Epoxy, Medium Hardener, Gallon kit
FR-1325A     1/2" x 5" roller (grooved)
EPX-P31     pump dispensers (3:1 = Medium)

I got plenty of extra mat, cloth and epoxy in case I want to do any fiberglass projects in the future. I expect I will have a lot left over after I fix my 1' x 2' section.

Thanks guys,

I appreciate the suggestions. TRBenj, I really appreciate the shopping list. It is probably exactly what I need too. Also, the prices of the US Composites products are great. I had been looking at some other distributors that specialize in boat repair supplies, and their prices were 2 and 3 times higher. David, you are probably correct on how the damage occured. The damage is on the high traffic side of the boat at the point were someone would step in off of the dock.

One more question. If I remove the entire soft spot, the hole will be close to the side of the boat. When I re-glass, should I run the last few layers up the side? If so, are there any tricks I will need know to deal with the vertical surface.

Thanks again,
Mark

   This is sound composite repair advice
the "taper" is called a scarf in the
composite world. One tip I'd like to
add is to cut open a plastic garbage bag
or wax paper and lay a layer of glass in
it, pour a small amount of resin on the
glass,fold the bag back over and use a bondo
type of squeegee to spread the resin into
the glass. Then use a sharpie to draw the
repair on the bag and cut it out with
sissors. Peel one side of the bag off and
install leave the top side on untill
your ready for the next layer of glass.
This will help control the mess.