Welding at Sea

[Cheechako]

Originally Posted by NeptunesTrident

Not only ABS, but AWS also. ABS is the authority on boats, ships and yachts. The Table I quote is for small steel boats. Yachts. I was not talking about larger ships.
Titanium would make a pitiful boat hull materiel. I don't know how you came to the conclusion it could be even remotely suited for a boat. Of any type.

Titanium is nearly impervious to salt water. welds wonderfully. 1/3 lighter than steel. The russians used to build their nuclear subs out of it. light, strong and non corrosive. unfortunately... really expensive!

[NeptunesTrident]

Originally Posted by Cheechako

Titanium is nearly impervious to salt water. welds wonderfully. 1/3 lighter than steel. The russians used to build their nuclear subs out of it. light, strong and non corrosive. unfortunately... really expensive!

Ok, Russians used to use it on/in subs. They did not build their subs out of it. They never used it in the hulls. They also use stainless steel, crome steel, inconel and monel. Not to mention others. Titanium cannot be welded with the SMAW process easly. FCAW and TIG processes are used. Mostly TIG. Titanium welds require AC current. Not that it is not avilable on board, it is. But the set up is expensive. Titanium is used mostly in aviation. Jet and rocket engines use titanium for some parts exposed to high temps. Nothing is impervious to salt water. As a matter of fact, the most powerful corrosive on earth is water. There is nothing it will not desolve given enough time.
Titanium has an ultimate strength of 1040mpa. A36 steel is 400mpa but will assorb shock much better. 1090 steel is 841mpa, 4130 steel is 1110mpa and your 2800 margining steels are 2693mpa. Titanium clearly falls in the middle of most of the steel grades. Your data is some what out of date.

[hellosailor]

While you folks are debating the finer points of molten metal, I would note that welders (as an occupational group) are apparently considered especially at risk for respiratory problems because of a fine mist of metal particles given off during the welding and inhaled. Which then lodge in the lungs and never get out.

Which would make the use of a particle-blocking face mask a very sensible idea, any time and every time you are welding. Never seen one rated as fire-resistant but I suppose that must be available these days too.

[Cheechako]

Originally Posted by NeptunesTrident

Ok, Russians used to use it on/in subs. They did not build their subs out of it. They never used it in the hulls. They also use stainless steel, crome steel, inconel and monel. Not to mention others. Titanium cannot be welded with the SMAW process easly. FCAW and TIG processes are used. Mostly TIG. Titanium welds require AC current. Not that it is not avilable on board, it is. But the set up is expensive. Titanium is used mostly in aviation. Jet and rocket engines use titanium for some parts exposed to high temps. Nothing is impervious to salt water. As a matter of fact, the most powerful corrosive on earth is water. There is nothing it will not desolve given enough time.
Titanium has an ultimate strength of 1040mpa. A36 steel is 400mpa but will assorb shock much better. 1090 steel is 841mpa, 4130 steel is 1110mpa and your 2800 margining steels are 2693mpa. Titanium clearly falls in the middle of most of the steel grades. Your data is some what out of date.

Well, I'm not going to continue an un-needed argument with you about titanium as it's absurd to think one will build a boat out of it. My point was just because ABS doesnt list an item doesnt mean it wont work for a given purpose. (and the owner's 52 ft boat above is evidently a good example.) I worked in Aerospace for 35 years and do know titanium forming and welding very well. Obviously you dont, because if you did you would know that ti is available in differnt alloys, purities and strengths just like steel.

[NeptunesTrident]

Originally Posted by hellosailor

While you folks are debating the finer points of molten metal, I would note that welders (as an occupational group) are apparently considered especially at risk for respiratory problems because of a fine mist of metal particles given off during the welding and inhaled. Which then lodge in the lungs and never get out.

Which would make the use of a particle-blocking face mask a very sensible idea, any time and every time you are welding. Never seen one rated as fire-resistant but I suppose that must be available these days too.

I have some. Mostly only use it when working with lead and copper though. Everything else we keep pretty well ventilated.

[NeptunesTrident]

Originally Posted by Cheechako

Well, I'm not going to continue an un-needed argument with you about titanium as it's absurd to think one will build a boat out of it. My point was just because ABS doesnt list an item doesnt mean it wont work for a given purpose. (and the owner's 52 ft boat above is evidently a good example.) I worked in Aerospace for 35 years and do know titanium forming and welding very well. Obviously you dont, because if you did you would know that ti is available in differnt alloys, purities and strengths just like steel.

Yeah, well I am still working in Aerospace. Diden't know you were that well versed in titanium as you posed it for a boat material. I quoted the alloyed titanium alloy for you. There are also a lot more alloyed steels than I mentioned. If you wish to consider unalloyed titanium, steel would be about 5% stronger than the same diameter rod as titanium, but titanium would be about 40% lighter. Unalloyed titanium is not as strong as steel. Like I said. Your data is out of date. Titanium is more ductile over a much wider range of temps than steel. But it is not stronger than steel. Never has been. I will not insult you like you tried to insult me above. I will just tell you to check your data.

As far as the boat builders are concerned, I said it was just my opinion. Several times. I would not use Cor-ten steels today on my boat when there are so many better options. 50 years ago is one thing, but sence the 80's there have been far better materials developed. Stronger and more resistant to rust. And if you wish to ignore ABS and build a boat, good luck with that.

[hellosailor]

Until the USSR collapsed, titanium was unaffordable to most of the US because the USSR had the greatest supplies of it and it was classed as a strategic metal.

Coincidentally...as I recall only the Soviets were able to build a titanium-hulled nuclear submarine. Because the alloy was quite suitable for boatbuilding, but the costs put it totally out of reach for Western nations.

Titanium bahtub to armor the cockpit in a Warthog? Affordable, to the military wallet. Titanium boat hull? Sometimes cost IS the entire issue.

[NeptunesTrident]

Originally Posted by hellosailor

Until the USSR collapsed, titanium was unaffordable to most of the US because the USSR had the greatest supplies of it and it was classed as a strategic metal.

Coincidentally...as I recall only the Soviets were able to build a titanium-hulled nuclear submarine. Because the alloy was quite suitable for boatbuilding, but the costs put it totally out of reach for Western nations.

Titanium bahtub to armor the cockpit in a Warthog? Affordable, to the military wallet. Titanium boat hull? Sometimes cost IS the entire issue.

It was a double hulled vessel. Only the inner hull was titanium. In theory, it would make the hull stronger. On another note. The sub sunk. The only proof we have of a titanium hull sub is the Komsomolets. And it sunk.

[Lodesman]

The Alfa's (Lira's) were titanium-hulled.

[SabreKai]

Originally Posted by NeptunesTrident

Nice looking craft. Well cared for it seems. Anything on repairs that have been made or refits?

She looks pretty much the same today. The stern was extended out a foot to give an overhang and protection to the rudder. The stern rail is history. The bulwarks are now a bit higher. There is now a tabernacle to allow the mast to be put up without a crane. There are other mods the cockpit area but from the side she's almost identical.

I miss her. She was a great boat to sail.

[chala]

Originally Posted by FUTURE DAYS

'Do-it-yourself' welding repairs at sea

Not to put a damper but I doubt you find a day calm enough to do serious welding on a 34 ft boat. Beware of fire; they start very easily, not the best place to fight them. Many marinas ban welding. In my view the vessel should be shipshape before proceeding to sea.

[NeptunesTrident]

Originally Posted by Lodesman

The Alfa's (Lira's) were titanium-hulled.

So it has been said. The problem with believing that is that we do not have evidence. If one remembers, the SU 27 was supposed to have used titanium also. But after getting one it did not. The Soviet's were famous for making claims. My question is IF it is true why did they not use it in their tanks and aircraft? I don't believe the claims. Like the claims of their aircraft using titanium, which did not, I am of the opinion the claims of the subs were also false.

[Anzo]

I've used both the aluminum and steel versions of HTS 2000 for smallish jobs with absolutely no complaints and no welder. Don't know if I'd weld my mast back together with it, but I'd likely be too wounded to care.
Aluminum Welding - Aluminum Repair - Aluminum Brazing - AluminumRepair.com

[bangkaboat]

So... back to the OP's question? I would expect that the OP is not planning to do much welding underway, except in an emergency. More likely, when in some place that is without facilities. So, a small inverter or alternator-driven or motor-gen that will give him DCRP should do the trick, without added expense of wire & associated parts, agreed? Now, here's another suggestion to push the thread sideways; I would recommend a welder capable of minimum 160A@60%+ duty cycle? Why? Ever gouge with 6010/11? When there is no cutting torch or plasma arc at hand, and you can't get to the repair with a zip-cut on a grinder, 6010/11 makes for a reasonable alternative.

[hellosailor]

From those rascals at the Wikipedia:

"High-strength alloyed steel is still the main material for submarines today, with 250-350 meters depth limit, which cannot be exceeded on a military submarine without sacrificing other characteristics. To exceed that limit, a few submarines were built with titanium hulls. Titanium is stronger and lighter than steel, and is non-magnetic. Titanium submarines were especially favored by the Soviets, as they had developed specialized high-strength alloys, built an industry for producing titanium with affordable costs, and have several types of titanium submarines. Titanium alloys allow a major increase in depth, but other systems need to be redesigned as well, so test depth was limited to 1000 meters for the Soviet submarine Komsomolets, the deepest-diving military submarine. An Alfa-class submarine may have successfully operated at 1300 meters,[2] though continuous operation at such depths would be an excessive stress for many submarine systems. Despite its benefits, high costs of titanium construction led to abandonment of titanium submarines idea as the Cold War ended."

By the way, the folks at Tab Books, who publish book club editions of almost anything technical, used to reprint the USN welding manuals, and the USN has extensive experience in practical welding at sea.

Welding, which means oxy-acetylene to many of us. And ARC WELDING, which is what all your fancy electrical stuff really is. Not welding, arc-welding.

There used to be some nice pages on the web supplied by the DOE about using plasma lances and other cutting tools--but those were taken down after the US was conquered by Al-Queda in 2001. Too dangerous for civilians to know how to cut structural beams.