Seacock/Through-Hull Replacement

[Stumble]

Originally Posted by Dockhead

My through-hulls are unbonded, so this is unlikely. Titanium would be the perfect material for this and many other marine applications, and I think hardly more expensive than bronze. I can't imagine why titanium is not more widely used.

Because my ex-boss would spend the $15,000 to have titanium ball valves designed.

The company I used to work for makes titanium thru hulls but no valves, and titanium and bronze can't be married under water, so you couldn't have a system. I begged and pleaded, but couldn't get any traction on the idea.

As for cost... A titanium thru hull would cost about 10% more retail price than a Groco bronze one, weigh 1/3 as much, and was about twice as strong.

[a64pilot]

"Stainless steel" is a very broad term encompassing many steel alloys, some are in fact magnetic, some not.

[Andrew Troup]

Originally Posted by Stumble

Because my ex-boss would spend the $15,000 to have titanium ball valves designed.

...I begged and pleaded, but couldn't get any traction on the idea.
.

I don't get it.

You say your boss WOULD spend the money.

Then you say you begged and pleaded.

Were you trying to persuade him NOT to spend it?

[Rustic Charm]

Originally Posted by Cheechako

I'm no expert, but to me a seacock is flanged and fits directly to the hull (or a backing plate), anything screwed onto a threaded pipe or thru hull fitting is a valve to me.
If you have standpipes that terminate above the waterline, then maybe a plastic valve is worth a shot, or I wonder if you could get a plastic reducer or coupling and use a bronze or SS ball valve? the plastic fitting would isolate the valve from the steel.

Using dictionary and all of my boating books indicate 'seacock' refers to any 'valve' that lets water into a boat.

I've now purchased two 'True-Design' plastic seacocks from New Zealand and I've fitted the first which is a 2 inch one for the head. They meet all requirements of safety within Newzealand/Australia so I'll see what they go like. I wanted to avoid stainless given so far two of the stainless ones in the boat were so badly corroded that one of them fell apart in my hand, luckily when I was on the hard stand. The other one had the spindle break in the closed position.

[Stumble]

Wouldn't.

Stupid autocorrect.

[Ukeluthier]

Originally Posted by Stumble

Wouldn't.

Stupid autocorrect.

Always amazes me the number of people who have autocorrect enabled and then fail to proofread their posts before hitting the submit button.

One would think an attorney would be more sensitive to such issues.

[goat]

Originally Posted by Ukeluthier

Always amazes me the number of people who have autocorrect enabled and then fail to proofread their posts before hitting the submit button.

One would think an attorney would be more sensitive to such issues.

[Marqus]

Originally Posted by tedsherrin

I've now purchased two 'True-Design' plastic seacocks from New Zealand and I've fitted the first which is a 2 inch one for the head. They meet all requirements of safety within Newzealand/Australia so I'll see what they go like. I wanted to avoid stainless given so far two of the stainless ones in the boat were so badly corroded that one of them fell apart in my hand, luckily when I was on the hard stand. The other one had the spindle break in the closed position.

I have had four TruDesign ball valves installed for 24 months - so far so good.
If there is swelling it has had zero effect on the mechanism; still smooth to operate. The manufacturer claims to have been aware of stiffness experiences with Forespar valves and designed their product to eliminate the same. Well, we'll see in five year's time.
Fire is a risk with these, but on the other hand they are not subject to galvanic effects or dezinctification.

[Andrew Troup]

It must be a special autocorrect algorithm* sold only in the US.

I must see that particular substitution at least twenty times from US posters (across a number of forums) for every once I see it from the rest of the world.

(And the latter only recently, whereas from the US, it predates the widespread use of autocorrect)

I wondered if it was an expression of relentless positivism which saw the positive form substituted for the negative.

*Ah *Ha*! maybe it was invented by Al Gore?

[Sondor]

Originally Posted by Andrew Troup

It must be a special autocorrect algorithm* sold only in the US.

I must see that particular substitution at least twenty times from US posters (across a number of forums) for every once I see it from the rest of the world.

(And the latter only recently, whereas from the US, it predates the widespread use of autocorrect)

I wondered if it was an expression of relentless positivism which saw the positive form substituted for the negative.

*Ah *Ha*! maybe it was invented by Al Gore?

...ROFL -

(perhaps auto-correct is an easy scapegoat?)

Al Gore: Those who know him best (TN where he was a Senator for over 20 years) gave their vote to Bush... That's really gotta sting! Statements such as the one (invented the internet) you referenced must have helped his credibility ~

[Dockhead]

Originally Posted by Stumble

Because my ex-boss would spend the $15,000 to have titanium ball valves designed.

The company I used to work for makes titanium thru hulls but no valves, and titanium and bronze can't be married under water, so you couldn't have a system. I begged and pleaded, but couldn't get any traction on the idea.

As for cost... A titanium thru hull would cost about 10% more retail price than a Groco bronze one, weigh 1/3 as much, and was about twice as strong.

I don't understand. Titanium ball valves are readily available from Modentic and other companies. Why would anyone need to design one?

[Stumble]

Originally Posted by Dockhead

I don't understand. Titanium ball valves are readily available from Modentic and other companies. Why would anyone need to design one?

This is going back a few years, but as I remember we couldn't license a design, and the designs on the market ass suffered from a few issues. Either they had a dissimilar metal problem, a titanium-titanium wear issue, or were designed for high pressure applications which made them very expensive.

It really came down to a market that they thought was too small to justify the outlay. While I kept pointing out that the switch to titanium would only cost the end user a couple of dollars per compared to bronze, so the market was huge.

[Cheechako]

The bottom line seems to be that when things do come out made of Ti... they end up extrememly expensive. I'm not saying it's necessarily justified. Try looking at Ti snap shackles!
The other problem I could see with valves is that ti on ti galls terribly without special treatment. Far worse than SS on SS. In addition, you cant just put Ti on a steel boat... yeah the ti wont corrode but I suspect the boat will be sacrificial..?

[Saltyhog]

Originally Posted by Stumble

This is going back a few years, but as I remember we couldn't license a design, and the designs on the market ass suffered from a few issues. Either they had a dissimilar metal problem, a titanium-titanium wear issue, or were designed for high pressure applications which made them very expensive.

It really came down to a market that they thought was too small to justify the outlay. While I kept pointing out that the switch to titanium would only cost the end user a couple of dollars per compared to bronze, so the market was huge.

You really *do* need to proof read anything auto-corrected. I agree that the market would likely be pretty good for an all titanium solution.

[Watercolor]

Of the two glass filled nylon ball valves, Tru Design and Forespar, the Tru Design is, in my mind, the far superior valve for marine use. It used far superior materials and is clearly a better design to both the Forespar 849/850 and 93 series.

The Trudesign valve is completely rebuildable, like any good valve should be. The materials Trudesign uses are a 30% + glass (fiber and ball) filled nylon for the housing and major parts. It has Tensile strength and flexural modulus values in full saturation equal to the Marelon product "Dry as Molded." (DAM) The ball and races are made of a very strong teflon.

I think you'll find these valves a good choice for a non-metal valve.

Jed