I just repaired a soft spot on our aft deck. We have a 48 LRC. It was very simple and here are the steps I used;
1. I drilled two 2" holes, with a hole saw about 4 " apart, in the bottom of the deck leaving the top cosmetics alone. Drill the holes appropriately to your area of repair.
2. Then got a long screwdriver and started scraping all the old wood out until I found a good patch.
3. Then made a mixture of West Epoxy 105 and 206, use the proper hardener for your temp, added West 406 silica and finally added cotton balls to the soup. Yes cotton balls, they are a natural fiber and make it easy to fill the voids.
4. Mix up this cocktail till the cotton balls are saturated. The mixture will not pour when held upside down.
5. Then started stuffing in the voids with a paint stick till I couldn't stuff anymore.
6. Put on a heat lamp so that the mixture will totally bond with the old glass.
That's it. No soft spot and tremendously strong and it was fun to do.
Stuart