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Telstar 28
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I've had a chance to see Steelboat's steel boat... and she is a beauty... currently a work in progress, but the work thus far is top notch from what I've seen. :) s/v Restless is a big beastie though. :) Her boom is a heavier extrusion than my mast, not too surprising though, considering the order of magnitude displacement difference.
 

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Yeah SD, it was nice to see you, and thanks for the kind words. You could probably sail to P'town and back in the time it takes me to get across the bay, but if I ever finish the old girl, at least we'll be comfortable as we make our way over.;)
 

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When I bought Billy Ruff'n (Van de Stadt Samoa 47 built professionally in steel) the first owner said the secret to keeping a steel boat Bristol is to "make her think she's not in the water". To do that you must start with a great paint system and then the owner has to love maintenance, keep a large inventory of Dremel tool bits handy, and maintain a well stocked paint locker. Repairs I made 4-5 years ago are still good, but it takes time and patience.

To give our prospective steel boat owner an idea of what's involved, lets repair a simple blister:

1/ grind it back to bright metal -- you have to find the edges of the rust spot and don't stop until you've found a clean line between well adhered paint and bright metal.

2/ Ospho it to 'convert' any rust that might remain in the tiny spots where the Dremel tool won't fit. (I never really understood what was going on with Oshpo, but I assume it strips off the O2 off the rust molecule and replaces it w/ something inert. Oxide becomes a phosphate?? Folks wiser than I might comment on this?)

3. Grind some more -- Dremel fine point diamond tools work well in the later stages of rust removal from tiny pits in the metal. When you've run out of patience you can stop.

(A note of caution when grinding rust spots -- have a shop vac handy to suck up the grinding residue. I didn't do this one day on a mooring and ended up with small rust stains down wind from the repair. The rust stains will come out with phosphoric acid.)

4. Apply a thin coat of etching primer (Interlux makes the one I use). Let it dry for at least an hour but not more than 24.

5. Apply one or two coats of epoxy primer (Interlux primer is a two part that is then thinned).

6. Fair the repair spot with a two part marine filler, sanding between applications of filler. Depending on the nature of the repair it may take two or three attempts with the filler and sand paper to get it right.

7. Apply another two coats of epoxy primer.

8. Apply two coats of finish paint. Wet sand the patch spot with progressively finer grits to blend the edges of the patch.

9. Apply what ever you use to protect the paint (polymer sealants or wax)

....et voila, a perfect patch. Note that it's only taken 5-6 days to get the various layers to dry. As I said, you have to love maintenance and a degree in chemistry wouldn't hurt.:)

The owner (or his boat yard, if the owner has big bucks) can deal easily with the exterior rust on hull and deck using something like the process outlined above. The interior is another matter. Here you really have to ensure that your boats designer and the builder knew what they are doing. It's said that most steel boats rust from the inside out, and I think it's probably true. Even in the best designed and constructed boat there are places inside the hull where the paint just doesn't want to go -- for example, try getting a paint spray gun pointed up at the underside of a limber hole deep in the hull. It's places like this that rust first. Welds are another potential trouble spot. Then there's the issue of how the hull is insulated and how the insulation gets in the way of water finding it's way to the bilge. There is little you can do to repair rust that may get going behind the permanently installed bulkheads (without ripping them out, that is). Doing a proper job of rust repair in places that are difficult to access is nearly impossible, so here is where you have to be confident that the builder and his paint crew did a first rate job -- and even if they did, eventually nature will take its course and the boat begins to bleed. (A point worth considering: interior of the hull should be white so you can see where it's beginning to rust). If you find a boat with dark paint in the bilges, you are probably looking at someone trying to hide something.)

I'll second everything said above about getting a surveyor who knows steel boats, but I'd also carefully check out the reputations of the designer and builder before buying a used steel boat. See if you can find other boats built in the same yard around the same time and talk with their owners. Make sure the surveyor gets out a bright light and small mirrors and really pokes around in the interior of the boat.

As for the strength of steel -- with a moment of inattention during the summer of 2006 Billy Ruff'n and I hit a rock at 6 knots. No leaks. We sailed it another 700 miles to a good yard where the boat was hauled. Damage to the hull was limited to loss of paint and fairing compound on the leading edge of the keel. It was easily repaired for about $2800. (We also put some hair line cracks on the leading edges of all the spreaders near where they join the mast). I am convinced that if we'd been in a lightly built fibreglass boat, our sailing season would have been over and the boat may have sunk.

Nothing stands up to rocks and careless owners like steel.
 

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Hi all
We sail a 48ft Steel Ketch and have done so for the last 30 Years! The boat was built in 1939, 70 years ago next year, and she is in “original condition” according to her last survey, and I can say that steel does stand up to groundings…. I have been there!!!!
We had an accident just outside our home port which will say in my mind forever.
We managed to put her up on an isolated head “20ft either way we would have missed it” unfortunately the first point of contact was the “plastic speed transducer” that smashed the flange off and then just “popped in” leaving a 2” hole in the bottom, she also split the frame down to the next frame, there wasn’t a “backing/compensating plate” this splitting wouldn’t have happened if a backing plate had been fitted.
As soon as it happened I realised we had a problem as the automatic bilge pumps cut in and we were taking on water.
I stuffed all I could get my hands on to slow the inflow of water that helped until the water was deeper than my arm length!!
We needed a “big” pump, which arrived half an hour after we had hit the rock, about the same time as my arms weren’t long enough.
During this time she was being picked up and dropped back on to the head ”she was stuck on the rock between the bottom and the bilge keels and it was quite frightening looking back on it” once we got the boat back it turned out the area that took the pounding was under the engine where the hull plate was pushed up about 3” even though it was “backed up” by the engine beds “10mm plate” it just folded this plate up and pushed in the hull plate but didn’t hole or crack.
I think the material that a boat it built out of is all a bit of a compromise, steel has its downside of if the coating gets damaged it rusts, and it is very correct when people say that steel hulls rot through from the inside out that was obvious when we originally purchased the boat 30 Years ago, however with the paints today they are very forgiving.
Fibre glass needs polishing etc once a year or more depending where you keep it this is quite a big job…
Wood looks good when the paint is just completed but as the material moves (shrinks and expands) as it dries out and then gets wet again the paint cracks and needs re-painting.
We have gone 5+ years without re-painting our steel hull, yes we have to touch up some rust spots but as has been explained it earlier posts a quick flick with a grinder and/or a wire brush and then just coating/filling as needed.
With regard to performance our boat weights about 20tonnes (probably a bit more than that) she performs fairly well with a modern hull, she doesn’t sail quite as fast as a modern boat or point as close to the wind, however when its rough she is very comfortable doesn’t bounce around and ploughs through the waves.
In my opinion steel makes quite a good cruising boat, as said before it needs to be over 40ft in size to get the benefits of steel, it might not be the fastest boat but given the conditions will perform well and if the weather turns bad, she will get you home.
If anyone is thinking of purchasing a steel boat get a surveyor who specializes in steel, look inside at all the bilge and anywhere where water can/could collect and check for corrosion/plate thickness. It could have a thin area that has been painted over. If you still want the boat contact the seller and haggle the price down, these “thin” areas can be replaced or repaired. I have been there, it depends what the boat means to you.
 

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Farr 11.6 (Farr 38)
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One quick point on Mallo's post. In the thirties the metal used was closer to iron than the high strength high carbon steel used today. That was actually good news as these low carbon irons were less rust prone and more malliable allowing them to survive much longer than the steels used after the WWII. That said, iron or mild steel will work harden making it more brittle than it started out.

I am glad to hear that the ole girl survived. May of these pre-war iron boats were truely works of art.

Respectfully,
Jeff
 

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Re. Jeff H's last post on iron as a building material

I've told myself that I'd quit sailing when I can't get it up any more (the mainsail, that is). One day I found myself researching alternatives to cruising sailboats and discovered you can buy canal barges in Europe that are over 100 years old -- all with hulls made of iron plates. Of course, they're used in fresh water and that must help -- nonetheless, it makes the point that if you take care of a metal boat it will last much longer than you will. ;)
 

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I recommend the writings of Bill and Laurel Cooper, who must both be past 80 now and own a large Dutch sailing barge with lee boards...very old school, but canal-capable. They did a nice if fairly opinionated book called "Sell Up and Sail" a few years back.
 

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There is in fact a huge difference in longevity of steel hulls in fresh versus salt water. Many people wonder at how "old fashioned" some of the ore boats on the Great Lakes look. They look that way because they are old-fashioned with many of the hulls approaching 75-100 years old. (that's not a misprint) The only thing that has done many of them in is the trend towards larger ships.

Most ocean-going ships now utilize a system called cathodic protection. This electrical system sets up a milliamp current through the hull which causes it to resist galvanic corrosion. I've seen plates abraded to bare steel that did not rust with such a system. Bottom painting used to be an annual event for these ships and it now is only done every two years, and then only as necessary upon inspection. Normal red lead or other bottom paints do not work with such a system; a special paint is required.

A passing thought based on Jeff's remarks on topside weight in a steel boat. The SS United States, the "Big U", was constructed with an aluminum superstructure and was one of the first, if not the first, to be built this way. (she still resides in Norfolk) The cost is prohibitive for average merchant ship construction but the weight savings are undeniable. It may surprise some that most modern warship's houses are constructed of aluminum for the weight savings. (the modern warship is no longer designed to be able to resist gunfire or missile strikes, the enemy is not supposed to get close enough for guns and missiles are to be shot down. the weakness of this theory in extremis was discovered by the British in the Falklands War when one of their frigates was struck by an Exocet missile. Aluminum burns extremely hot, especially when an aluminum-magnesium alloy is used.) While expensive due to the construction techniques required, an aluminum topsides could be entirely feasible. (i probably should have said, prohibitively expensive!)
 

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There is in fact a huge difference in longevity of steel hulls in fresh versus salt water. Many people wonder at how "old fashioned" some of the ore boats on the Great Lakes look. They look that way because they are old-fashioned with many of the hulls approaching 75-100 years old. (that's not a misprint) The only thing that has done many of them in is the trend towards larger ships.
I would beg to differ... The great lakes is not exactly 'fresh water' it is brackish... The difference between old steel and new steel - is that todays engineers desire the smallest weight to have more buoyancy in their 'scientific' designs which comes at a cost in terms of selecting whatever grade of steel - 100 years ago - big and heavy was beautiful (and according to the personals on Craigslist - its making a comeback)...as it was equated to 'indestructible' (ie titanic) and metallurgy was something of new era... Imagine if modern epoxy was invented 150 or 300 years ago - huge wooden ships - not steel would of become the norm for commercial vessels...

One also has to consider the upkeep of vessels in pre-today eras. Now the goal is to minimize the amount of upkeep. In the earlier days - a Captains pride was the vessel. So upkeep in terms of painting, and the likes was carried out more fastidiously resulting in a greater lifespan of the vessel.

The are lots of factors that end up being considered but 1900 era vessels were up kept to a more stringent maritime tradition and had thicker steel... Today light and minimum upkeep when even it is admitted in scientific circles - metallurgy is not a exact science and maritime standards have actually been reduced to expected lifespans and the cost of mininal labor upkeep and etc....
 

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While expensive due to the construction techniques required, an aluminum topsides could be entirely feasible. (i probably should have said, prohibitively expensive!)
My pilothouse has an aluminum "lid" or roof for this reason, but the sides are steel. The key (particularly as wiring is run through said roof) is to isolate the metals from one another as much as possible, just as one would using steel bolts on an aluminum mast.
 

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Telstar 28
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Valiente-

Just curious, how is the aluminum connected to the steel?
 

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"The great lakes is not exactly 'fresh water' it is brackish."

With all due respect, the Great Lakes are not brackish by the accepted definition of brackish.

"Technically, brackish water contains between 0.5 and 30 grams of salt per litre-more often expressed as 0.5 to 30 parts per thousand (ppt or ‰)."

http://en.wikipedia.org/wiki/Brackish

"Fresh water is defined as water with less than 0.5 parts per ten-thousand dissolved salts"

"Freshwater lakes, most notably Lake Baikal in Russia and the Great Lakes in North America,"
http://en.wikipedia.org/wiki/Fresh_water

"however, Lake Ontario has a rather high salt content
(about 185 ppm: Beeton 1965; about
235 ppm: Dobson 1967). The average
salt content is roughly 0.209% in salinity,"

http://www.aslo.org/lo/toc/vol_22/issue_1/0158.pdf

I expect Lake Ontario has a somewhat higher salt content it's downstream location from Erie, Huron, et al.

For what it's worth, I've kayaked Georgian Bay and, to a lesser extent, Lake Superior and drink the water from the lake. It is definitely fresh.
 

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Valiente-

Just curious, how is the aluminum connected to the steel?
With about 28 1/4" bolts, some tapped into the aluminum cross-frames, others secured with Nylock nuts where accessible. Lucky me, I got the bolts off last weekend, only to find that a thick bead of 5200 is also holding the roof down firmly. 5200 is a glue, not a gasket or a bedding compound, to my mind, so now I have to get a couple of Chinatown bread knives and get sawing.

Yes, I am buying a few tubes of dielectrical goo, and I need to seal over some previously drilled and inadequately capped holes that allowed water to intrude and which has rusted a bit of the flange. It's not bad, but I can reprime and topcoat the whole thing on any day above freezing.

I suspect I will use a continuous strip of rubber gasketing outside of the boltholes when I replace the roof.
 

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Jody,
It probably would come as a surprise to those communities that get their drinking water from the Great Lakes to hear it categorized as brackish. Potable water standards do not allow for salt in drinking water. Since the average fresh water allowance on a ship is 10" it's important that one know the specific gravity of the waters one will be transitting. I've always measured a SG of 1.000 on the Lakes and my employers would have been sorely plexed had I not loaded deeper and been able to. (g)

The longevity of the newer ships on the Lakes will probably equal their predecessors even though they are now constructed of thinner, lighter, stronger high-tensile steel. Most ocean-going ships are not done in by corrosion as they are by stress, increased maintenance costs, and the advances of technology. Great Lakes ships experience far less stress than ocean-going ships, they only sail nine months a year, and there is far less maintenance to be done on them. The advent of catodic protection systems has allowed ocean-going ships to reduce their shipyard visits from annually to bi-annually. The ABS and USCG have seen the results and only require dry-docking every two years instead of annually as required on those older ships you refer to. They certainly were built heavier, but not better in most respects.
 

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steel-aluminum join

Sailing Dog, steel hulls with aluminum superstructures are a routine way to go with big stuff, from super yachts to war ships as sailaway 21 has noted. It's usually done with a dupont product (in this country) called a deltastrip or deltacouple, which is a bi-metallic strip, explosively formed, which joins the 2 materials together (don't ask me exactly how). You then simply weld the steel to the steel and the aluminum to the aluminum. In europe it's called tri-clad. I believe there may be a third element (composite or other?) between them to allow for the different coefficients of expansion in big stuff. I'm told the stuff is quite expensive, but in mega yachts the weight savings up high negates the cost of the strip. In smaller boats it's pretty simply done with bolts and flanges, as long as everything is properly isolated, as Valiente has apparently done. Hope this helps. Bob www.sv-restless.com
 

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Telstar 28
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Bob-

The material I'm familiar with is called Triclad, and is IIRC a laminated strip with aluminum on one side and steel on the other.
 

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Telstar 28
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In smaller boats it's pretty simply done with bolts and flanges, as long as everything is properly isolated, as Valiente has apparently done. Hope this helps. Bob www.sv-restless.com
Well, I will do it, because I'm going into salt for the first time next year, and I notice that some of the steel bolts didn't come out without a lot of persuasion this time. So a proper coating on the bolts and tapped threads, plus a gasket of some description to keep the aluminum roof from directly contacting the steel flange (which itself will be ground, primed and painted entirely).
 
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