Tank content calculation software

Fresh/Waste Water Systems, Watermakers, HVAC, Refrigeration...
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Michel
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Re: Tank content calculation software

Post by Michel »

katorpus wrote:That shutoff in the vent line is just there in case you find yourself in conditions where a rollover is imminent...
I recently studied a couple of yacht disaster reports (Fastnet Race 1979, Queen’s Birthday storm 1994 btween Fiji and NZ and Sydney-Hobart Race 1998). You'd be amazed how often water was entering through small or big built-in holes causing problems. Even when knocked flat you could get water in through the diesel vent line. Ever thought of what would happen in a knock-down if your cockpit locker hasps have no locking mechanism other than a padlock? Right, I am replacing my hasps with a version with a swivel padeye to secure them without padlock. And I'm making a securing pin in my companionway washboard. And I looked up the lids that were supplied with the transom air scoops and put those lids with the safety gear. All other dorades I replaced with modern Plastimo ones with a self closing mechanism in addition to a manual lock from inside. I also replaced the large flat Perko anchor chain lid with a swan neck type hawsepipe with lid. Look at all modern boat factory yachts; they are outfitted with vents and slides and grids as if they are RV's and only have to cope with vertical rain.
Last edited by Michel on Tue Feb 10, 2009 4:22 am, edited 2 times in total.
Michel Capel, Freedom 44 #4 1981 'Alabama Queen', NED8188, cat ketch with wishbones, home port Enkhuizen, the Netherlands, 52*42.238'N 005*18.154'E.

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GeoffSchultz
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Re: Tank content calculation software

Post by GeoffSchultz »

I am replacing my hasps with a version with a swivel padeye to secure them without padlock.
If these are the Perko hasps, my experience with them is that within a year or two they corrode and don't swivel. Perhaps that's my lack of exercising them, but this is what has happened to mine.

-- Geoff
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1997 Freedom 40/40
http://www.GeoffSchultz.org

katorpus
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Re: Tank content calculation software

Post by katorpus »

Why not just leave the original hasps?

When you get ready to go out (and no longer need the security of the lock), you take off the padlock and replace it with a small, snag-free snap shackle (or a mini-carabiner)...or a whittled stick for that matter.

You could keep it tethered to the hasp with a piece of light line and it would always be there where it's supposed to be instead of down in the cockpit grate or drain somewhere.

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THATBOATGUY
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Re: Tank content calculation software

Post by THATBOATGUY »

katorpus wrote:Why not just leave the original hasps?

When you get ready to go out (and no longer need the security of the lock), you take off the padlock and replace it with a small, snag-free snap shackle (or a mini-carabiner)...or a whittled stick for that matter.

You could keep it tethered to the hasp with a piece of light line and it would always be there where it's supposed to be instead of down in the cockpit grate or drain somewhere.
Exactly. I've even used dog clips.

George
George and Kerri Huffman S/V Marquesa Freedom 40 CC CK Sail MarquesaImage

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Michel
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Re: Tank content calculation software

Post by Michel »

Smart guys you are! I thought of a wooden dowel but those would get lost in a day. But a smal carbiner with as piece of string is a good idea. Anyone has a KISS way to secure the washboard?
Michel Capel, Freedom 44 #4 1981 'Alabama Queen', NED8188, cat ketch with wishbones, home port Enkhuizen, the Netherlands, 52*42.238'N 005*18.154'E.

katorpus
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Re: Tank content calculation software

Post by katorpus »

There's a tradeoff between function & beauty here...

If you use slide bolts (on the inside of the washboard, into holes in the trim adjacent to it), then the board is no longer "flat" when storing.

For pure utility, a vinyl strap with the lift-off curtain buttons (not the lift-a-dot) would do it.

You'd put a "male button" (the kind with a screw in the center) in the bulkhead on the cockpit side centered below the washboards and another inboard opposite it (behind the ladder, below the bottom of the companionway), and run the strap up, over, and back down. It would have to be strong enough to hold, but thin enough to allow the hatch to close over it (but you'd only use it when you "might need it"...too wide and you'll run into problems with the curve at the top of the washboards.

You could then release the strap from either the cockpit or inside the boat.

For sure you don't want to close the hatch and put anything in the hasp if anybody's down below...the time it might take them to kick their way out might be more than they have to save themselves...nevermind if the helmsman goes overboard or gets incapacitated.

The reason not to use the lift-a-dot is that little male spike would be prone to "holing" a knee or a bare toe.

On your "whittled dowel", you could always drill a hole in one end, tie a piece of small line (like nylon mason's twine) on it in a loop, then pass one end of the loop through the hasp hole, followed by the dowel through the loop end that you passed through the hasp, cinch it down & not lose that dowel. When time comes to put the padlock back on, just undo it, leaving the loop tied together. Same works for the carabiner, the "dog leash snap" or anything else. If any of them are "loose", sure enough they'll end up "gone" when you take one loose to get something out of the locker.

fmolden
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Re: Tank content calculation software

Post by fmolden »

Two of the three swivel hasps have failed on my 13 yr old boat (F35). Both failed at the swivel. Apparently they just push the swivel through the hasp and swedg it in place just enough to let it swivel but stay in place. With any load it will pop out of the hasp. Not a real secure device for security. Offshore I found that the swivel can rotate and could align itself in the open position, so a pin of some sort is still a good idea.

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Michel
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Re: Tank content calculation software

Post by Michel »

Fred,

I suppose you had the Perko hasps. They are made of Zamac (zinc/aluminum) with a layer of chrome that keeps them shiny until the warranty is gone.I think the zinc is added to make them heavier, so they feel like iron. Zamac is only suitable to cast Dinky toys, i.m.h.o.. There are now reasonable quality (made in China) cast stainless replacements.
Michel Capel, Freedom 44 #4 1981 'Alabama Queen', NED8188, cat ketch with wishbones, home port Enkhuizen, the Netherlands, 52*42.238'N 005*18.154'E.

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Michel
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Re: Tank content calculation software

Post by Michel »

katorpus wrote:
If you use slide bolts (on the inside of the washboard, into holes in the trim adjacent to it), then the board is no longer "flat" when storing.
I was thinking of a slide bolt, but then with the bolt on the trim edge and the hole (2/3 of the way) in the washboard. I was still chewing on the best place to mount the slide bolt. You don't want to tear your clothes when entering the cabin. So the bottom outboard corner is probably the best location; the washboard is so low there that you can reach over it from outside to open the bolt.
Michel Capel, Freedom 44 #4 1981 'Alabama Queen', NED8188, cat ketch with wishbones, home port Enkhuizen, the Netherlands, 52*42.238'N 005*18.154'E.

AlanK
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Re: hatchboards

Post by AlanK »

To your question about hatchboard holddowns. I’m trying to come up with a better method but on my old boat I screwed in eyestraps on both sides inside and outside of the companionway below the top of the lowest board (if yours is in several sections like mine). I ran lines on each side. They could be released from inside or outside and used to hold down 1, 2 or all of the boards and the eyestraps were on the sidetrim so not where they could be stepped on. I did not have to drill holes in the boards for the lines as there was space to get it through even with all the boards in.
It worked well but involved either getting the tension right or retying each time. I’m considering this approach again but maybe instead of eyestraps small clam or jam cleats.
Alan

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