Frame locations in a 1984 Stingray?

Hello Just acquired a 1984 Stingray 19' bowrider. Only a few spots of rot in the plywood sole, but I have found the foam underneath to be saturated with water. In the winter, I will cut out most of the plywood and re-sole it. But now, before using it, I want to get out some of the water. I plan to drill 3" holes in the plywood down the middle of the cockpit sole, drilling one hole in each compartment ("compartment" meaning an area under the sole between floors (cross members)). Then remove foam with a thin-walled tube (like taking core samples) to open a passage down to the inside of the hull bottom next to the keel. Then I can wet-vac out water which should migrate down to the lowest point. BUT, I don't know the locations of the floors and I don't want to drill down into structural members. Can anyone tell me approx. where the cross members are located? Thanks much. Tedpop in Connecticut.

 

Each model and manufacture use different stringer and structural load bearers, none are the same, even if the same model out of the same mold.

The foam of that era boat will not drain out its moisture, trust me. Some will come out, but not that much. The foam needs to come out and be replaced with a closed cell variety, which will not absorb moisture. You'll see the stringers when you hack out the foam after removing the sole. It would be a wise idea to make some "weep" holes in those stringers and other structural elements, so moisture can move aft and be pumped or drain overboard. Minimum diameter for a good weep hole is 3/4" or bigger. Generally they are the same diameter as the thickness of the piece they penetrate. Arrange them so moisture can't collect or pool in the below sole spaces and that they will permit the moisture to flow aft to a drain or sump.

The foam is easy to remove. A hand saw will do a fine job and let you know if you've run into something more substantial then some foam, before you do real damage. Solvents can work too, especially on the final removal of the little pieces, that seem more stuck then the rest.

 

Thanks for your thoughts, Par. Limber holes are a possibility, though I would not want to compromise structural members if they are not already wet, unless the holes could be well sealed with resin. Probably they are all rotten. Isn't it amazing that boat builders persist in thinking they can keep water out of a compartment and close it off from human access. Like life, "water will find a way." If only builders provided a way for it to get back out.