Underwater viewing pane in hull ?

[boony]

Hi all,

I'd like to put a viewing pane in the bottom of the hull just for the pleasure of looking underwater. Maybe a bit radical for alot of people but anyway it would be quite small, about 20 x 15cm. I've seen one on a Sydney based racing yacht and it was used to check the canting keel.

Anyone with experience of this ?

Several questions :

Safety and leaks ?

Material ?

Underwater growth ? Obviously I can't use antifouling. Can I expect a couple of weeks use in Sydney Harbour (sub-tropical) before having to dive overboard to wipe the slime off ?

Or am I just nuts

[Bergalia]

Originally Posted by boony

...Or am I just nuts

Just nuts boony.

Not worth the trouble when a plastic bucket with a perspex bottom inset will do just as well. No worries about leaks of hull weak spots, growth etc. On top of that it's more manouvreable than the hull.

[boony]

But what about staring at the little mermaids from the comfort of my bunk

[charmc]

Originally Posted by boony

Hi all,

I'd like to put a viewing pane in the bottom of the hull just for the pleasure of looking underwater. Anyone with experience of this ? Safety and leaks ?
Material ? Underwater growth ?

boony,

The racing yacht example involved people feeling a need to see structure below while at speed. The other example of vessels with clear viewing panes are tourist boats. Both have income streams to pay for frequent hauling and maintenance.

Why introduce a source of extra maintenance if it's not necessary? Devices with clear plastic bottoms for viewing are readily available, as are plans for making your own.

[Bergalia]

If you're staring at mermaids from the comfort of your bunk, boony - you've sunk....

[charmc]

Originally Posted by boony

But what about staring at the little mermaids from the comfort of my bunk

There's a thread on submarine yachts.

[DungBeetle]

boony, don't listen to any of these people, they are obviously old and feeble.

you must install an underwater view port.

this is the obvious way forward. the colours you get when parked near a reef are just brilliant. Lexan is the obvious choice, 5 times stronger than steel, and to all intents and ordinary purposes indestructible. it will be the strongest part of your yacht by FAR. bonds well to epoxy if prepared correctly.

i was going to do this myself but in the sugar scoops. (so it would be really handy if you would do this first before i build)

cheap, fun, this will be the best feature of your boat.

[boony]

Yes, still considering this option. I think its perfectly feasible and just needs to be done properly. My only doubt was how long it would take for slime to start masking the view and was going to do some local testing. The problem is Ive put the renovation of my boat on hold as Im moving to Singapore which is a pity as I had lots of ideas I wanted to try. If you go through with it maybe you could post some pix.....cheers

[waikikin]

I think that toughened glass of 15mm in the size your proposing may resist scratching better than Lexan/acrylic but would be more ideal built into a sea chest with bolt on/ wingnut cover in case of trouble, there was a vessel at Shell point(in Sydney) slips with a sub wl window to check on propeller. Regards from Jeff.

[the1much]

we built an apogee 55 for a dude with a "porthole" hehe,,the old guys in the yard just shook their heads and snickered. he LOVED it.
morale of story,,listen to the old dudes,,3 years later we hauled the boat and made it into a boat again not a sub,,and filled the hole hehe er,,,i fergot ta add,,,,,it looked like CRAPOLA,, he used divers and it still looked like it was 50 years old,,even the glass that was pose to be o.k for this, was "pitted" and started to have a hint of "plexi" look to it

[tallen]

boony,
If you did this I would recommend lexan cause I have seen it used quite successfully (though on the great lakes).

Something else to consider would be (assuming your boat is of the right size) you could get a hydraulic or pontoon lift to pull it out of the water while at dock to minimize the fouling on the lexan.

Could also use a Biocide based anti-fouling paint on the hull and that should further reduce fouling on the lexan even if the lexan itself is uncoated due to the way the biocides work.

[TollyWally]

I have a pretty cheap underwater video camera that my girlfriend got me last Christmas. It's black and white not color. It's a little cheesy but pretty fun, we call it CRAB TV.

[StrandedMariner]

The Spanish Navy has underwater viewing panes in their ships. This enables them to have a look at their previous Navy

[captaintrue]

Instead of building it into the hull, if your boat is large enough I'd have a small 5' x 5', bouyant underwater viewing platform capable of being towed or put over the side. The platform can a reasonably sized window made of two layers of thick lexan in its bottom to allow you to view underwater. Of course the viewing section would need to extend below the waterline.

[Brent Swain]

I used to have one. Most of the time all I saw was mucky green . I could have painted the floor that colour and I would have seen the same thing. I eventualy welded it shut, as friends did with theirs..
It had a 1/4 inch plate cover over it , held down by 4-half inch and 4- 5/8th inch bolts, for safety ,and a lexan cover under that which protected it from anything dropped from the inside. I never had any trouble with leaks. International makes a clear antiofouling paint for glass bottom boats . It needs a lot of drying time before immersion or it goes foggy. Works on plexi, but not lexan.
Plexi window in the dinghy was better , but too much glare reduced it's usefullness.
Give it a miss.
Brent