Patching two 1.25" holes in the deck

[GreyingEagle]

I bought my first SF ('79) and discovered it weighed almost 170 lb. I naively followed some online instructions and drilled two 1.25" inch holes in the deck -- one a few inches aft of the bow handle and the other just aft of the traveler -- as starter holes for inspection ports, only to discover flotation foam directly beneath them both. (The hole for an inspection port aft of the splashguard worked much better.) Now I have the task of filling the other two holes. Should I go ahead and enlarge them to take 4" inspection ports that don't serve any useful purpose? (Seem simple.) Or should I try to patch them with fiberglass. (Seems complicated.)

 

[L&VW]

Or should I try to patch them with fiberglass. (Seems complicated.)

As BB has written previously, installing inspection ports don't really affect the strength of a Sunfish deck.
http://sailingforums.com/threads/removed-screw-and-the-backing-block-fell-off.33428/#post-150061

Your unintended ports can be "made useful" by removing some of the flotation (or structural) foam to the nearest open area.

Since you already have the hole drilled, a hole saw can't be skillfully used to change that size; although a thin sheet of plywood could be tucked under the deck, centering a spot for starting the hole saw's ¼" bit.

Use of a saber saw will, of necessity, cut into the foam anyway. At the bow handle, that foam to be removed would be directly aft of the hole.

There may be inspection ports available that are smaller than 4". I have a rubberized bug screen designed to fit a 3" port, which would be handy when storing the Sunfish inverted. (Alas, I have no port in which to put it).

 

[L&VW]

...or you could simply glue a 1½" plug into each...

http://www.rockwestcomposites.com/products/1218

 

[GreyingEagle]

L&V, thank you for your prompt and generous replies. That black plug and some marine caulk might be just the ticket. I can use an Exacto knife to carve out some of the flotation material and might escape enlarging the holes altogether. I'm not sure what will hold the plug in there, but I think it's worth a try. There are some parts of your other response that I don't quite understand. (Remember I'm a newbie.) When you say remove "foam to the nearest open area," are you suggesting that I slice off a chunk of foam and glue it to the underside of the deck somewhere else? Do I try to remove an entire block of foam. How is that done? I understand that using a hole saw means finding a stable spot to center it. But how would I get a stable piece of plywood into that tiny hole? If I wanted to enlarge the hole, wouldn't it be easier to use a jigsaw or a keyhole saw that don't require a stable center? Thanks also for your patience in explaining these things (and your thoughtful and patient responses elsewhere on this board).

 

[L&VW]

When you say remove "foam to the nearest open area," are you suggesting that I slice off a chunk of foam and glue it to the underside of the deck somewhere else? I understand that using a hole saw means finding a stable spot to center it. But how would I get a stable piece of plywood into that tiny hole? If I wanted to enlarge the hole, wouldn't it be easier to use a jigsaw or a keyhole saw that don't require a stable center? Thanks also for your patience in explaining these things (and your thoughtful and patient responses elsewhere on this board).

I did a search for "factory tour", and found the location of those white Styrofoam blocks. It's the darker foam that will pick up moisture, and you can see that there's a lot of it!

That's a lot of "open area": you just happened to put a hole above one of the structural foam members.

The boat won't miss the little pieces you remove, and will make the present errant holes useful as 3", 4", 5", or 6" ø inspection ports for drying out high moisture content. By shopping around ("plastic plugs, images"), you may find a plug (in white) that will snap right in, be watertight, and be difficult to dislodge. To install the suggested plugs, all it would take is some exterior-grade "Liquid Nails" to hold them in place—or you could use some other waterproof adhesive. "Liquid Nails" is a serious product.

To center a hole saw, I'd cut a tongue depressor in half, drill a centered ¼" hole, and glue both ends to the underside of the hole. In a short time, you'll have a centered spot to start the hole saw. Since the ¼" hole is already there in the tongue depressor, you don't have to use an actual drill bit—just use any ¼" aluminum stock or use even a wood dowel! Use of a saber saw or keyhole saw is an option, but a messy one.