Watertight cockpit floor with large hatches?

[Ron Williamson]

Has anyone done this?It is next on the list.
Maleo has a cockpit about 4' wide and 6' long,with steering gear and stowage underneath.The scuppers are in the transom and at the forward corners.I was thinking about building two hatches as large as possible,raised above the actual floor about 2".The hatches would then be the walking area and the cockpit floor would be a gutter all the way around and between the hatches.
As for material,I like ply around 5/8",with beams under.SWMBO's pa votes for teak(EEK!)
What do you think?
R

[dasboat]

Ron,FYI.Our Gatsby has a cockpit deck that is built similar to what you describe.
The 4'x4'hatch is piano hinged.When opened,there are large gutters(1" deep/3/4" wide)with 3/4"copper drain tubes that exit at the transom.
Gatsby is a motorboat with the cockpit enclosed,so I have never seen this system work as it might have to in a storm or shipping water.I have hosed out this deck area with plenty of water,and not found any water below in the tank room.

[Ron Williamson]

Thanks Darryl
I didn't think of building drain troughs under the deck.
I may have to cipher that out.
R

[Bob Cleek]

Yep, you've got it right. We did that on my boat some time back and she doesn't leak a drop. You have a larger cockpit, mine being about 2x4, so your hatch gets heavier, but... you basically build up a lip around the opening and then a hatch that sits on top of it like the cover of a shoebox. It won't keep water out if it rises above the level of the lip, but if that happens, a little leak below is the least of your problems. The rainwater will run over the edge of the hatch and into the gutter between the sides of the cockpit and the lip. As far as I know, short of a submarine hatch, there isn't any way to keep a flush cockpit hatch from leaking! Be sure to take into account whether you ship water through the scuppers when heeled. Some cockpits are so close to the waterline that they do that, in which case your lip is going to have to be high enough to account for that.

[Bill Griffin]

I am going to have to build a hatch for my cockpit sole, eventually. About the size of Cleeks. There must be a reference out there somewhere with designs? I think I would want solid hardware to hold it down also. Previously, there was a 10" round bronze hatch that was the only access to the stuffing box and rear of the engine. I had to remove the sole, which led to opening the entire interior, so I have some time (LOTS!) before I get to this, but it's something to think about. There was some interesting stuff under the old cockpit sole. I want access in the future for cleaning, etc.
Still a couple weeks or more before I can start work on rebuilding, though. What I thought was going to be a winter project may take a couple, years. I plan on posting plenty of pics once I get going.

[PeterSibley]

Pursuing this idea a bit further , how about having the whole cockpit structure as a removable hatch ? Obviously not for day to day removal but for serious ( or even ocassional ) maintainence of that most inaccessable of places ....behind the engine .That place where you can't move or see or swing a spanner ! The hatch is a great idea but the next step is the whole thing . Disconnecting cockpit drains would be the only necessity and that should be easy enough with some of the newer hardware around .

What do you think ?

[Ron Williamson]

I suppose pictures of the final result would be in order?
R

[JimConlin]

If you can tolerate the weight (and cost), I like the robustness of the Bomar cast aluminum hatches.

[tomlarkin]

...how about having the whole cockpit structure as a removable hatch?

I'm making my cockpit sole this way. It's mostly a gas tank below, so I don't think I'll need to get in there very often. I'll screw the sole down on a rubber gasket and caulk the edges (not 5200 ) once I've verified everything works correctly. The space is well ventilated up under the aft deck so it shouldn't get too musty. I have an inspection port so I can keep an eye on things down there.

[Ian McColgin]

Both Goblin and Granuaile had simple hatches that sat down over combings with the happy addition of a gasket around the inside of the hatch cover (around the combing would get mucked up when gear is brought out of the hatch) and 4 screw dogs, one centered on each side, to keep the contact.

In flooding tests where I filled each cockpit, looked for and staunched leaks, noted how much she squatted, and then unsealed the scuppers to time the drainage, I found these hatches admitted an acceptable small amount of water during the few minutes the cockpit water level was over the hatch cover.

If you have an off-shore yacht, will use it as such, and have not done a cockpit flooding test, you are not a serious sailor.

[john92021]

Pursuing this idea a bit further , how about having the whole cockpit structure as a removable hatch ? Obviously not for day to day removal but for serious ( or even ocassional ) maintainence of that most inaccessable of places ....behind the engine .That place where you can't move or see or swing a spanner ! The hatch is a great idea but the next step is the whole thing . Disconnecting cockpit drains would be the only necessity and that should be easy enough with some of the newer hardware around .

What do you think ?

I've heard of this taken further where the cockpit was used as a dingy

[donald branscom]

Has anyone done this?It is next on the list.
Maleo has a cockpit about 4' wide and 6' long,with steering gear and stowage underneath.The scuppers are in the transom and at the forward corners.I was thinking about building two hatches as large as possible,raised above the actual floor about 2".The hatches would then be the walking area and the cockpit floor would be a gutter all the way around and between the hatches.
As for material,I like ply around 5/8",with beams under.SWMBO's pa votes for teak(EEK!)
What do you think?
R

You are putting the boat at risk out at sea.
If it stays in the harbor it is ok.
Big hatches leading into the interior of the boat HAVE sunk boats.
Never have a cockpit locker open to the interior of the boat.
Bad idea as far as I am concerned.
A cockpit has to be able to be drained quickly of a wave comes aboard.
And then if that "stowage" gets loose in the steering gear or cables you will have problems.
I have seen boats with stowage in that area and it is usually rotten sails,rotten old cheap life jackets,tangled up line and all sorts of junk that was just dumpster fill. Some of it was in there for years but no one wanted to get down in there and pull that rotten old stuff out.

I say keep your boat seaworthy ,CLEAN and engine and steering gear with a lot of fresh air all around it.

[Candyfloss]

A removable cockpit floor would have been a godsend on "Candyfloss". The water pump, the shaft seal, the coupling, the fuel tank & the exhaust system were all under there, all pretty much inaccessible. I had a little hatch in the floor for inspection, but you couldn't get your hand in & see anything at the same time. To replace the impeller, it was easiest to pull the motor out!

[paladin]

I sealed Tana Mari's cockpit and built a "soft patch" in the cocpit floor. If I need to seriously get anything out, I could cut through it with a mallet and chisel, then grind/plane away the edges and use epoxy and xynole tape to reseal the hatch. There was enough room to crawl into the area from inside the boat, but I needed to pull the hatch to remove the engine.

[Bill Griffin]

Like I said above, there's a lot more to do before I rebuild the cockpit. I think I'll likely build it a bit smaller than the old. I'd like to install a hatch for lazarette stowage. Maybe something like Paladin has done, a soft spot that is well fastened but removable for maintenance. The old drains were too small, not crossed, and the through-hulls are below the WL. This is not a blue water boat, but I have been uncomfortable with the old arrangement.

[floatingkiwi]

I am gonna make one like this. Glass across deck and completely down into and out to the interior of the gutter. Drain tubes whereever best , removable and hingeless.

[cookie]

I will probably build the hatch on my boat like Ian McColgin's, but then with a double seam. One seam of simple rubber and another caulckable. The caulckable seam to be closed only when going on longer journeys on open water, kinda like Paladin's system....

[Candyfloss]

I need to ask Paladin a question here.

Chuck. I've made one minor excursion in my life, from New Zealand to Tonga, but not the return. You have circumnavigated three times. So the question is, how many times in all that mileage, did a wave jump out of the ocean & fill your cockpit? In other words, how real is this threat? In a boat, say, smaller than 40 feet.

It seems to me that in the event of a knockdown, or God forbid, a rollover, a perfectly watertight cockpit floor would be the least of your worries.

[floatingkiwi]

I am not speaking from experience here, but,( Hi Graeme), I can picture the bow submerging and green water making its way across the entirety of the vessel and the cockpit being filled dozens of times all in one storm. Is this a realistic scenario?

[paladin]

The worst I have ever been in was the Indian Ocean. One storm, and it was a lulu......I rode it out on a drogue and a bridle......I was most aprehensive about the Horn......somewhere a year or two back I stuck a photo on here.....it was a walk in the park...calm, and no waves to speak of.....
The next one that had me worried was the North Atlantic. I had the hatches glued shut, I had on my heavy cold weather undies, the bow was diving, and a half mile away a German freighter continued to disappear in the troughs.....and water/spray was freezing the moment it hit the rigging....I was scared that a chunk of the ice would fall on my head....it did put a couple of dents in the deck.
For a while I owned a 43 foot fib*&^%$#@$$ (can't say it) boat that I chartered in the islands.. It had a cockpit hatch with compression latches and rubber gaskets over the engine.....it leaked like a sieve no matter what I did to it, and it was a center cockpit boat. When I built Tana Mari, it had no engine, but I installed the goodies to add one, including the soft patch to install it....worked like a charm.
All my ventilation would draw from the bilge, so no openings to the outside world except exhaust ports...bilge was always sweet and dry. When running offshore...I closed everything when sailing at night, and then anchored my harness in the cockpit...sometimes I would greatly reduce sail in the open ocean and nap in good weather, otherwise I would round her into the wind, drop the drogue, make dinner and enjoy myself, and sleep with the running and spreader lights on.