1930 Steel Sailboat

[serracoelho]

Hello community,
I'm sorry if this question was already posted.

I want to buy a 1930 Steel Sailing boat, with a complete hull refit in 2006.
The boat is owned by the same person since 1980, and he really loves and takes care of the boat.

In the 2006 refit all the cockpit and cabin were replaced from old wood to stainless steel and the hull blasted and reinforced.

The owner is selling the boat with almost new sails, and good navigation, the engine is from 1995 (SABB) with very good maintenance.

My question: Is it risky to buy a steel boat with almost 100 years old?

Thanks a lot.

[Jim Cate]

Opinion only!

Buying any used steel boat is risky in that most boats have areas that are difficult to inspect for rust, and internal rust is a common failure point in steel boats.

If the boat has been well maintained for ALL of its life, and if a really good inspection shows no glaring faults, then I'd say the risk isn't excessive.

Another factor is the type of steel used. If it was Corten (as some early steel yachts used) the risks are somewhat lessened.

All just opinion without personal expertise or experience.

Jim

[PirateGuy]

According to Professor Wikipedia, Cor-Ten Steel wasn’t developed until 1933, and it was developed for other reasons rather than corrosion resistance. That means there’s no chance a sailboat built in 1930 could have been constructed with Cor-Ten.

[MicHughV]

Here is a simple test....you can buy a metal thickness gauge on Amazon. A reasonable on will set you back $2-300. There are many to chose from.
Very simple to use, press the little foot against the steel, and it will readout the thickness. Very accurate too.
You do need to know the original plate thickness so you have a yardstick to go by.
With this in hand, and the boat out of the water, you can test the hull thickness every 18" or so along the length, from sheerline to bottom. Take a notepad with you, and record all the readings. You will likely have several 100 of them by the time you are done.

Should you get a reading that is low, suggesting a problem, you can fan out from that spot to identify the extent of the problem. The low reading will also give you a clue where to look at inside the boat. Should you need to repair a suspect area, this is also reasonably simple to do. If you know how to weld, you can do your own repairs, if not, steel workers are readily available.

Just seeing rust, is not an indication of a problem. Steel can throw of an amazing amount of rust before a problem exists. As a rough guide, a 1" thick plate can throw of 10" of rust.

Finally, steel is amazingly strong, even a 1/8" thick plate is much stronger than you think. The tensile strength of steel is typically 50,000 to 60,000 psi...about 4 or 5 times that of fiberglass and has much greater impact resistance than fiberglass.

Steel gets a bad rap due to some unsightly home built hulls, but do some due diligence and go from there.

[jordanbettis]

1933 boat definitely wasn't made out of corten.

Anyhow, the original corten wasn't a great boatbuilding steel as it was high in phosphor and therefore was fracture prone in cold water. Modern variants (A-588 and A-606) don't have this problem as they're low phosphor.

The main thing to do is to get a thickness survey done. A boat from the 1930s probably isn't welded, but riveted, so you should make sure there wasn't pack rust in the seams. The thickness survey should be able to see the seams as being twice the thickness as the surrounding sheet.

I'll hazard a guess that this boat isn't too expensive, so it won't really be a big financial hole for you if it's a lemon. Something to keep in mind as you review the negativity that you're sure to get from this forum.

[jordanbettis]

Originally Posted by MicHughV

Here is a simple test....you can buy a metal thickness gauge on Amazon. A reasonable on will set you back $2-300.

Would not trust a thickness gauge on amazon. Additionally, a super cheap one probably can't take soundings through paint (even if it says it can).

Figuring out the original thickness is part of the fun. One way is to compare one side of the boat to the same part of the boat on the other. The other is to think rationally about how a boat is constructed (if the bilges come in thinner than the deck, you have a problem).

Another thing to think about is the parts of the boat that will have the most problems: The wind/water line, the anchor locker bottom, water traps in the bilges, high wear areas on deck. You can compare these areas to parts of the boat that would have had the same scantlings originally but would have had an easier life. Corrosion is typically quite localized.

[MicHughV]

I beg to differ....I am retired now, but am a structural marine engineer by profession. I bought a $300 metal thickness gauge from Amazon, as I did a lot of work on the waterfront....ports, harbors, etc...and used it to gauge the remaining thickness on steel sheetpile...in many areas I was able to correlate the actual metal thickness with what the gauge read....

I also built my own steel boat, When I sold it, the new owners had the hull sounded, from top to bottom. That hull had several layers of paint on the outside, but it didn't seem to bother the sounder as the readings were all in line with the original hull thickness.

These sounders usually come with a very precise thickness chunk of steel to use as a reference point. If you suspect the sounder is not reading something right, you can check it against this chunk of steel.

[jordanbettis]

I have a Defelsko and I agree with everything you have to say about the virtues of a good ultrasound. But I did not buy it from Amazon and it was not $300. But maybe everything you say is true and I got ripped off by an American lab equipment manufacturer and should have gone with China, dunno.

[Westcliffe01]

Doing a hull thickness survey is fairly simple and the equipment for it wont break the bank. But remember than you still have to consider pitting. Pitting features will often be too small to detect reliably with a thickness gauge. For that a visual inspection would be needed and can be confounded if there is thick paint in the bilges and other areas where water may collect and electrolysis is possible.


For the plating to be uniformly reduced in thickness would suggest that large surfaces had been exposed without paint for a very long period. This would be fairly unusual. What is much more common is a ding or scratch in the paint exposing a small area which is preferentially attacked. If the hull was painted with zinc rich primer as its first coat, this offers some sacrificial protection, but not forever. Without it, rust loves to spread under the paint layer and as the rust expands it bubbles up the paint, exposing fresh surface to attack. Anyone who has ever owned a car in the midwest knows exactly what this progression looks like.


So my advice is to have someone knowledgeable on steel hulls be part of the inspection because they know problem areas when they see them and can investigate appropriately.

[Fore and Aft]

Is she welded or riveted? When did they start welding steel yachts?
Have you got a photo? I imagine she must be a sweet shape and well worth saving? You might have to get her vinyl wrapped so it looks like she is planked. That way you can hang out at all the classic wooden boat shows!
Cheers

[serracoelho]

Thanks a lot for all the comments, I really appreciate it.

Regarding the hull inspection, I'll buy a thickness gauge for future measurements if I take her, but since I still need to learn a lot about steel, I asked already for a professional full survey.

Also keep in mind that she had an extensive refit in 2006 from a professional yard here in the Netherlands.

Regarding the boat design, she is a 33ft double ender designed by Max Oertz, one of the greatest German yacht designers. She never stopped sailing since then, mostly the North and Baltic seas.

I will share some pictures soon.
Thanks again for all your comments, I will take a look on the gauge.

Best,
Rodrigo

[RaymondR]

There are at least two great advantages to steel boats. Provided they have not been allowed to corrode they could be thousands of years old and still as sound as the day they were built. And they are very easy and cheap to repair.

Steel is what is known as a very honest material, if it has a problem it is readily apparent. Unlike many other boat building materials a careful inspection will identify any potential problems.

[MicHughV]

The Dutch have a very long history with steel boats, so this fact alone, sounds promising.

My own steel boat, now approaching 40 years old and on it's 3rd owner, is still going strong, still in excellent shape.

[dannc]

Questions to ask:

• Is interior of the hull painted?
• If so, how was the hull prepared for painting?
• What paint was used?
• As mentioned in previous posts, what plate thickness was used when the boat was built?
• Is the boat insulated, and if so, how?

Later,
Dan

[MicHughV]

While I was building my steel boat, also got the opportunity to see several other steel boats being built, both by homebuilders and professional yards.

I had the choice of using 1/8" thick plating or 3/16" plating. I opted for the 3/16" thick plating as I was concerned about welding heat distortion, but 1/8" plating would have been perfectly acceptable. I'm wondering myself, of the plate thickness a 1930's hull would have had??

While spray in foam is pretty much the norm these days for steel hulls, I used 1" styrofoam panels, but only down to the waterline, and I think most steel boats follow this pattern, so as to make the hull plating visible below the water.

Paints have come a long way since 1930. If the paint was redone in 2006, pretty good odds they would have used the latest product available. As long as the hull was sand blasted prior to painting, odds are good, that the steel is good. Not sure how the interior was done though ??

The interior of my boat was coated in two part coal-tar epoxy, marvelous stuff, you can pour this paint onto virtually anything....it sets rock hard, completely waterproof.

Most all steel boats these days get a zinc paint as the first paint that goes on, this is usually followed by two coats of primer, and at least two finish coats......

That this boat was redone in 2006, points to the fact that it is likely in relatively good shape. If it passes survey, got for it...