leaky hatch, project?

flo617 · #1 (**permalink**) 10-11-2011

Hello,

The forward hatch on my Columbia 29 is leaking slightly from the box. The box is wooden and is somehow encased in the deck with caulking all around it (see attached pictures). Apart from the leaks it feels fine and solidly attached.

I don't know how to un-mount it and I'm not sure I really want to do that as the bottom appears to be nailed. Although the nailed part might just be a decorative bottom frame, I'm worried of destroying the whole thing in the process.

What I was thinking of doing was to sand the gelcoat down to fiberglass about 1 inch around the box on the deck, sand the wooden box, fiberglass the box and the 1inch of stripped perimeter with two or three layers of cloth and cover with gelcoat. The wooden hatch lid would stay wooden as it does not appear to have any issue Almost all the boats I see around have a fiberglass(ed) hatch box.

Does that sound like a reasonable thing to do?

Thank you for your inputs,

Florent

SloopJonB · #2 (**permalink**) 10-12-2011

Quote:

Originally Posted by flo617

Hello,

The forward hatch on my Columbia 29 is leaking slightly from the box. The box is wooden and is somehow encased in the deck with caulking all around it (see attached pictures). Apart from the leaks it feels fine and solidly attached.

I don't know how to un-mount it and I'm not sure I really want to do that as the bottom appears to be nailed. Although the nailed part might just be a decorative bottom frame, I'm worried of destroying the whole thing in the process.

What I was thinking of doing was to sand the gelcoat down to fiberglass about 1 inch around the box on the deck, sand the wooden box, fiberglass the box and the 1inch of stripped perimeter with two or three layers of cloth and cover with gelcoat. The wooden hatch lid would stay wooden as it does not appear to have any issue Almost all the boats I see around have a fiberglass(ed) hatch box.

Does that sound like a reasonable thing to do?

Thank you for your inputs, Florent

What you are planning sounds like a quick & dirty patch, not a proper fix.

I would recommend removing the whole thing and properly rebedding it. I am all but certain that the lower "box" is fastened up through the deck from underneath, either by large wood screws or by machine screws and nuts - are there any plugs showing in the wood on the topside of the "box"? If there are, it is probably fastened with machine screws.

On the underside, the strips that make the seam the leak is coming through are decorative trim to cover the large fasteners and the cut edge of the hole in the deck. Remove those strips and you should find the heads of the fasteners that hold the hatch assembly on. Remove the fasteners and the hatch assembly will come off, ready for cleanup and rebedding.

Doing it properly will ensure it is good for another few decades.

rugosa · #3 (**permalink**) 10-12-2011

SloopJonB is right. Don't put a bandaid on it, fix it right once. That hatch box will be secured by screws from underneath. If you take it off it will be easier to also refinish the box on a work bench, remove hatch from box to reseal and then install the whole assembly back to the deck. If there is enough board width router a groove in the bottom to accommodate more sealant on the install. Good time to replace the old fasteners too.

flo617 · #4 (**permalink**) 10-16-2011

Thank you for your advives. So today I manage to remove the teak trim without tearing it appart. Behind it I found... a big nothing!

There is just the wood and a 3 to 5mm gap to the deck. The wooden box is two frames (inner and outer) glued and/or screwed so I guess it is the outer part that is attached to the deck. How exactly I`m not sure as there is no visible screw neither on top nor on the bottom.

SloopJonB · #5 (**permalink**) 10-16-2011

Quote:

Originally Posted by flo617

Thank you for your advives. So today I manage to remove the teak trim without tearing it appart. Behind it I found... a big nothing!

There is just the wood and a 3 to 5mm gap to the deck. The wooden box is two frames (inner and outer) glued and/or screwed so I guess it is the outer part that is attached to the deck. How exactly I`m not sure as there is no visible screw neither on top nor on the bottom.

Hmmmm.

Do you have a molded fiberglass liner as an overhead? If so, the hatch may have been mounted prior to the deck being attached to the hull, in which case the heads of the fasteners will be between the liner and the deck. I have a number of things fastened that way on my Columbia.

There have to be fasteners holding the hatch assembly to the deck, it's just a matter of finding them. Does it look like any holes have been filled in the area under the trim you removed?

SloopJonB · #6 (**permalink**) 10-16-2011

In your first picture I can see evidence of plugs on the face of the teak trim. Is it possible that the hatch was secured horizontally through the hatch coaming into the edge of the deck cutout? I would have thought the deck was too thin to do this but I can't see any other reason for those plugs to be there. Do they go all the way around the coaming? Can you see any other reason for them being there?

flo617 · #7 (**permalink**) 10-16-2011

No these are higher than the deck. I'll take some more pictures tomorrow.

flo617 · #8 (**permalink**) 10-16-2011

So, I've explored a bit more and I think I got it now. The fasteners seem to be on the outer side and were hidden under the rubber that was used as a gasket. It seems there are two per side. The horizontal fastener on the inside are probably keeping the inside part of the frame connected to the outter part. I tried to draw a little diagram of what I think is going on.

I wonder if I'll be able to extract the plugs without too much trouble or if I'll have to grind them down to the screws.

Hartley18 · #9 (**permalink**) 10-17-2011

Quote:

Originally Posted by flo617

I wonder if I'll be able to extract the plugs without too much trouble or if I'll have to grind them down to the screws.

That's the hundred dollar question.

If it was done properly the first time around, you should be able to dig them out - carefully..

Just out of curiosity: How are the hinges attached? Hatches like yours usually get leaks through that way.

SloopJonB · #10 (**permalink**) 10-17-2011

Quote:

Originally Posted by flo617

So, I've explored a bit more and I think I got it now. The fasteners seem to be on the outer side and were hidden under the rubber that was used as a gasket. It seems there are two per side. The horizontal fastener on the inside are probably keeping the inside part of the frame connected to the outter part. I tried to draw a little diagram of what I think is going on.

I wonder if I'll be able to extract the plugs without too much trouble or if I'll have to grind them down to the screws.

From your diagram, you should only have to remove the vertical screws - that should let you lift the whole assembly out in on piece. You may have to slip a putty knife under the frame to cut through the caulking.

As for removing wood plugs - use an awl and punch out the middle, then working outwards, remove them bit by bit. Don't get greedy and try to take to much at one time. If you can't avoid damaging the edges of the plug holes, you can overdrill them the next plug size up - just make sure you don't drill deeper than the depth of the plug. A quick "depth gauge" is to put a strip of masking tape around the drill bit at the correct depth and leave the tape ends sticking out like a flag - it will sweep the dust away when it touches the wood.