Ferro Cement Boat

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hollywood8118 said:
The big issue is that the re bar expands and the water continues to follow the steel.. which causes the plaster to spall.

They are interesting hulls.. and this one looks like a good example. Insurance is the biggest gamble buying a ferro boat.
HOLLYWOOD
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The reason for rebar expansion is do to galvanic corrosion. That corrosion then causes spalling of the cement. There are many technical articles relating to problems that result in concrete embedded rebar.
 
makobuilders said:
If you approach it in that way then make a low-ball offer on the boat,

If you could pick up that vessel for 45-50k and it is sound, then you'll be a happy skipper dude.
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Wow, that is a low offer, but I agree with you, of course. I hope our ' broker ' friends here in the forum will not get angry with you.... lol
They did with me, when I was debating low offers/negotiations in another post.

I like ' unique ' boats and something different, so this boat is attractive to me, too. My main concern is to have a safe and long lasting boat. I really don't care what is it made of, or how it looks, or does it have a microwave, or not..... Since, there are not many FC boat surveyors around here, it could be difficult to come to a final conclusion on the safety and possible lifespan of this 55'-er.
 
foggysail said:
The reason for rebar expansion is do to galvanic corrosion. That corrosion then causes spalling of the cement. There are many technical articles relating to problems that result in concrete embedded rebar.
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Not quite. Galvanic corrosion requires contact of two dissimilar metals of different voltage potential. Corrosion of steel in this situation is common environmental corrosion known as "rust".
 
foggysail said:
The process is described at PCA - The Portland Cement Association - America's Cement Manufacturer for those interested. Also many rebar reinforced concrete structures are protected by ICCP...impressed current corrosion protection systems.
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When steel rebar is exposed and forms a layer of rust the diameter of the bar actually grows, only when the bar is open to the elements does this rust shed and the bar is reduced in size. The initial expansion of the bar is the cause of the material ( a ferro boat isnt actually concrete.. more of a plaster really ) is pushed away from the bar. In ferro boats that used "rebar" in their construction it is actually there to form the hull and the smaller diameter mesh is the real reinforcement for the plaster.

HOLLYWOOD
 
makobuilders said:
Hello skipperdude, my opinion is that you need to approach this vessel as a fun "project boat." Let me explain what I mean - even if it is in perfect condition, the truth is that a ferroboat has pretty much no value on the market. You have to think that you are investing in something that is fun to own and use and it is entirely sunk cost. Do not expect it to be any sort of investment. A used Nordy or Grand Banks could be an investment, but not an esoteric project boat.

If you own and use it for 10-20 years then at the end you might want to just salvage the engine, gear, windlass and other items - perhaps sell all of that for about 15-20k, then just sell off the hull for about 10-20k itself.

If you approach it in that way then make a low-ball offer on the boat, wait 3-6 months and if it doesn't sell then approach the guy again. I know all of this from my own experience both as a buyer and seller of a project boat.

If you could pick up that vessel for 45-50k and it is sound, then you'll be a happy skipper dude.
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The boat in question actually has value, not in the traditional book value we see in boats though. If someone gets it for say $50k.. and maintains it in the same condition and sells it in 5-10 years it may still carry the same 50k value. The value is in what the boat can do vs other boats of similar size.
This boats looks like (without crawling around it) a pretty decent example of a ferro boat.. and has definitely held up ok. I had mine for nine years and actually made money on the deal when I traded her away for a almost perfect SeaRay. So I came out on the winning side of ferro ownership. The boat in question has cool mechanical's. I dont really care for its looks that much but if I was looking for a 50' boat to cruise and insurance wasn't any issue I would seriously look at it. My ferro boat took way less to maintain the hull and deck than my current Ocean Alexander with teak decks
HOLLYWOOD
 
boatpoker said:
Not quite. Galvanic corrosion requires contact of two dissimilar metals of different voltage potential. Corrosion of steel in this situation is common environmental corrosion known as "rust".
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Exactly!


Only the highest quality metals should be used for internal reinforcing on boats containing cement mixtures.


"Post Tension" concrete slabs on commercial buildings are tension-arch held in place via multi strand stainless steel cables surrounded by close tolerance plastic tubing that has multi-thousand PSI tensions pulled via specialized equipment. This building technique enables great sized non supported expanses of elevated concrete slabs. The good quality cable coated with grease, incased by non-perforated plastic surround protects against any combo of and/or any type moisture ever damaging the tensioned metal cable


Additionally... "cement" [i.e. Portland Cement I and II - at whatever %age utilized in a "mix"] is simply the hardener-catalyst, not the end product. Alongside many other additives that cement can become a setting agent for or with, such as granular aggregates [sands/pebbles/stones], fiber additives, polymers, calcium, Acryl 60... etc, etc... products such as concrete, mortar, grout, ferro are the hardened item outcomes.
 
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There is a technical disagreement here pertaining to galvanic corrosion of rebars in cement boats. I agree that an anode (the rebar), cathode (other metal) electrolyte and a return path are required for a galvanic corrosion problem. The "other metals" can be anyplace where electrons can flow through an electrolyte. In a boat there are many places for this to happen. The electrolyte is salt water wetted cement and the other metals are anywhere especially the boat's own exposed metal such as shafts, rudders, props.

The rebars cannot be buried to significant depths in the thin hull cement to prevent exposure to minute cracks especially if the vessel is purposely designed to allow flex.

Crevice corrosion should also be considered as a problem source. To my knowledge plastic coated rebars were nonexistent some 25-40 years ago, the era when cement boat construction was popular. And I certainly remember a couple of boats being built here in Massachusetts that used chicken wire and not plastic coated rebars.

I don't want to get hung up on semantics.....I am referring to cement, concrete, plaster, paste in reference to these boats.
 
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Ferro boats are hard to sell or insure where ever you are, no different here in Australia.
This one looks like a goodun and has stood the test of time.
I am really impressed with the fittings , engine and variable speed prop.
I would happily pay 40 k for the engine and prop set up alone.
The 6L3 or 6L3B is either 102 hp at 800 RPM or 153 HP at 1200 RPM and weighs 2.65 ton.
Would be a perfect set up in a nice big displacement cruiser.
The one it is in now would be good as long as you knew its limitations.
 
foggysail said:
There is a technical disagreement here pertaining to galvanic corrosion of rebars in cement boats. I agree that an anode (the rebar), cathode (other metal) electrolyte and a return path are required for a galvanic corrosion problem.
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and an electrical (physical) connection of the dissimilar metals.
 
Tidahapah said:
Ferro boats are hard to sell or insure where ever you are, no different here in Australia.
This one looks like a goodun and has stood the test of time.
I am really impressed with the fittings , engine and variable speed prop.
I would happily pay 40 k for the engine and prop set up alone.
The 6L3 or 6L3B is either 102 hp at 800 RPM or 153 HP at 1200 RPM and weighs 2.65 ton.
Would be a perfect set up in a nice big displacement cruiser.
The one it is in now would be good as long as you knew its limitations.
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That's exactly how the perfect future owner of this boat needs to feel about the transaction. There's plenty of value here but the hull is a liability IMO. That Gardener and CPP is the bulk of the value and can be pulled and sold separately at some point in the future to recoup part of your investment if the hull ever did go completely pear shaped.

Really belongs in the Interesting Boats thread.
 
CPseudonym said:
... There's plenty of value here but the hull is a liability IMO. That Gardener and CPP is the bulk of the value and can be pulled and sold separately at some point in the future to recoup part of your investment if the hull ever did go completely pear shaped.
Really belongs in the Interesting Boats thread.
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Were it not for the age of the boat I would raise the same caveat about the hull, but it has had 43 years to disintegrate or show signs it is about to. It does not appear it has recent work to keep it from or stop it looking like falling apart. If it passes survey, considering the value elsewhere in the boat, the potential purchasers budget, and larger boat aspirations(which I think border on "courageous" if not "character forming"(acknowledgement to Sir Humphrey Appleby),surely it merits a good hard look, with a thorough hull survey as the starting point.
 
Hence what I suggested - make an offer, pick it up in the 45-50k region, and you'll most likely be a very happy cruiser (assuming no surprises during survey).
 
IMHO - Owning a construction co for decades and having professionally/personally worked with masonry, tile, concrete, stucco, and plaster for over 40 years (as well as having invented well selling hand-held pressure injection grout tools):


There is a way to create a pressure injection, vibrating system... employing high grade internal mesh support... for building "ferro" boat hulls and decks and superstructure. Brought to its fullest capabilities (especially with modern "cement" composition additives utilized to their fullest) I believe this "ferro" boat building system could be made to turn out super rugged and durable light weight boat parts faster than any other building means. Labor costs would be slashed during hull, deck, and superstructure sequences. Of course... the cost to originate and well-design this boat building method would cost millions at the onset. That said - this method might drop the cost of boat building low enough to capture substantial sales opportunities in the marine industry.


Anybody got millions to invest in a new boat building method that could sweep the pleasure craft (maybe commercial craft too) boat building industry?? Feel free to contact me via PM... :D


Happy Boat-Building Daze - Art :speed boat:
 
makobuilders said:
Hence what I suggested - make an offer, pick it up in the 45-50k region, and you'll most likely be a very happy cruiser (assuming no surprises during survey).
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Exactly. If you look at the YW photos, the last one, showing the stab. fin, has some rust bleeding out. Also, the surface is a bit different, pain or repairs, right above the fin.
A good and knowledgable surveyor is a must! It is not easy find one, these days....
 
Sailor of Fortune said:
Even if the structure is very good, the resale market is just about non-existent for Ferro cement boats. Steve Seaton designs excellent boats. The problem is not in the design, its the construction (justified or not).
In the 70's, many were singing the praise of the beautiful boats that any amateur can make in their driveway. Consequently, many crudely built homemade tubs were launched. Ferro got a HORRIBLE reputation.
Some real boat builders made fine boats but they are all suspect because of the many bad ones.
If I were you I'd happily sail your current rig (nice boat) or keep lookin - you can do better!
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I'm with SOF. Some years ago, I put 1500 offshore nautical miles on a ferro cement sailing yacht. It was thoughtfully designed and superbly built. I trusted that thing with my life, and would again, but I didn't want to own it then nor would I now.
 
From the couple FC boats I have personal knowledge of, one is still afloat, but just as a weekend condo, doesn't move. The other one was a finely fitted out 50' or so ketch rigged yacht. When you looked at her even from near she looked like a 'normal' looking hull. The builder/owner did an outstanding job finishing her off. But what mother nature did he couldn't repair.

Then one night during a Nor'easter she broke her mooring outside the granite breakwater. After she was salvaged the owner had her put in a parking lot. There was a total of about two square yards (meters) of holes and ground down past the rods and mesh. And the center of the keel was open to the bilge. The owner eventually hired a front end loader and took her to the dump.

There seems to be NO way to perfectly mate cured concrete to new concrete underwater use, that can withstand the flexing between the old and new.

That said: If you find one and can enjoy it, what the heck! Go for it. But it may have limited chances/choices to repair if it ever comes to that.

Here's an example of a boat that has vanished after a grounding and subsequent 'repairs'. home

I found out about her on CF, and did some research. 2013 was not a good year.

After reading up on the topic years ago I learned of the 'Cement Barges' and Cement Ships' concept that was tried in WW2 for cheap (disposable) bottoms to ship material overseas. The practical limitations to hulls (which by definition MUST be able to flex to stand the seas) are limited to around 300'. Anything longer than that flexes. And Cement doesnt 'flex' well. This was discovered during trial and error experimentation which cancelled the larger 'freight hulls' that were being tried in the war. http://www.concreteships.org/ships/ww2/

I would suspect that cement repairs would flex off and not be a safe repair. The concept of a FC hull is a Unibody, inflexible, rigid hull. No flex is allowed. How can a damaged FC hull ever be trusted?

If you ever fly into ORF you can see remnants of the hulls on the eastern shore piled up and making sort of an artificial harbor.
 
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Repairing that hull type. How about

sand blasting the entire hull down a good 1/4 inch
repair holes with epoxy and some kind of fiber filler maybe kevlar like.
use epoxy and Kevlar cloth to form a new bottom.
Although kevlar may be difficult to wet out I have read, maybe another fiber is ok, even fiberglass.
 
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@sdowney717. That type of repair is a 'last ditch' way to patch up old wooden hulls. A sure sign of 'the end' from my experience. The problem isn't "the entire hull" with FC. It's the fully cured Portland Cement that you are attempting to attach new cement to in a repair/patch. There is NO penetration and no adhesion between the new and old. Any flex, bump, distortion of the hull and you have instant gusher.
 
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Veteran sailboat yachtsman Syd Fischer built at least one ferro-cement racing sailboat called Ragamuffin (there were several boats, were they all ferro, not sure), nicknamed "The Flying Footpath" (some might say 'Sidewalk") which he raced extensively including the famed and almost always tough, "Sydney-Hobart". I don`t recall any report of structural issues.
Sounds like the boat utazo89 is looking at has gone, even so,I best take each such boat on its individual merits.
 
I was the project manager for surveying the ten concrete ship breakwater ~13 years ago.

If anyone is truly interested having a ferrocement hull surveyed, I have a list of some pretty good contacts. All ACI members.

Half cell potential measurements would be high on my list of NDT requirements for a survey.

SS would still likely have its passivation layer while embedded in the paste. Pitting corrosion due to high chlorides is more probable.

There are quite a few Samson hulls still on the BC coast. They seem to attract very long term owners.
 
cappy208 said:
@sdowney717. That type of repair is a 'last ditch' way to patch up old wooden hulls. A sure sign of 'the end' from my experience. The problem isn't "the entire hull" with FC. It's the fully cured Portland Cement that you are attempting to attach new cement to in a repair/patch. There is NO penetration and no adhesion between the new and old. Any flex, bump, distortion of the hull and you have instant gusher.
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My idea was use epoxy and a cloth either kevlar or FG, dont use cement.
Does any think epoxy won't stick to cement? I did a little googling, and people patching holes in FC did use epoxy.
 
It may stick. But is your life worth it? IMHO There is nothing wrong with FC. Until it needs major post accident repairs. Then whatever investment you have is just about worthless.

You can get modern epoxies to stick to steel hulls too. Doesn't mean it's an effective or dependable long term repair.

To see how epoxy/ fiberglass flexes, next time you are out in rough weather find an accessible part of the underwater hull. Place your hand on it and feel the flexing of the hull.

Epoxy and fiberglass flex. Cement doesn't. I don't think anyone can absolutely 100% guarantee mixing two types of dissimilar products like this. Well.... maybe a TV pitchman.
 
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With so many better options and the "bad "we know about FB boats why would anyone even contemplate owing one then realising there mistake then trying to sell it ????


Then again ppl have been known to buy JEEPS
 
Art said:
IMHO - Owning a construction co for decades and having professionally/personally worked with masonry, tile, concrete, stucco, and plaster for over 40 years (as well as having invented well selling hand-held pressure injection grout tools):
Click to expand...
Art said:

There is a way to create a pressure injection, vibrating system... employing high grade internal mesh support... for building "ferro" boat hulls and decks and superstructure. Brought to its fullest capabilities (especially with modern "cement" composition additives utilized to their fullest) I believe this "ferro" boat building system could be made to turn out super rugged and durable light weight boat parts faster than any other building means. Labor costs would be slashed during hull, deck, and superstructure sequences. Of course... the cost to originate and well-design this boat building method would cost millions at the onset. That said - this method might drop the cost of boat building low enough to capture substantial sales opportunities in the marine industry.


Anybody got millions to invest in a new boat building method that could sweep the pleasure craft (maybe commercial craft too) boat building industry?? Feel free to contact me via PM...
Happy Boat-Building Daze - Art
Click to expand...

_____________________________________________

As I say above in previous post #74 [pg. 4] in this thread (see quote above)... and as the following video shows [originally supplied by sdowney717 - on post 47 this thread]... cement mixtures have come a long way for durability and usability as compared to yesteryear. Building "ferro" cement boat is already considerably inexpensive (on more than one level) than other boat building methods. And, the quick turnaround ferro-build method I've designed would slash labor costs as compared to known methods. I can see that "flexible", durable, incredibly strong, and easily surface-fared cement mixtures with internal support structures (non corrosive plastic coated metals) and revolutionary ferro material quick-building methods could become the new rage in pleasure craft construction. Ferro-build boats may become a commercial game changer for new boat cost reductions and therefore increased boat sales. :D

 
@Art

Can a FC hull be repaired if it is holed? Can the old cured cement be structurally joined to a 'new' cement patch? Allowing No water penetration?

I don't see anyone arguing whether cement is cheaper, or whether they are unsound.

But if they are damaged (beyond surface scuffs) can they be repaired? This seems to drive the resale value down. ( which seemed to be the crux of the thread)
 
cappy208 said:
@Art

Can a FC hull be repaired if it is holed? Can the old cured cement be structurally joined to a 'new' cement patch? Allowing No water penetration?

I don't see anyone arguing whether cement is cheaper, or whether they are unsound.

But if they are damaged (beyond surface scuffs) can they be repaired? This seems to drive the resale value down. ( which seemed to be the crux of the thread)
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There are ways to do it currently and better ways being devised. For me to authoritatively answer your question I'd need to be in test labs and then onsite with field experiments of actually damaged/repaired hulls.

I recommend you visit Super-Krete | Concrete Products | Concrete Repair Products - Super-Krete I've known John (the founder) for decades and used some of his super binding, flexible products. After decades... he recently sold his operation to an organization, but stay on as consultant. This all began back in the 70's or 80's with Chevron pouring hundreds of millions into chemists and other high techies for creating new and better surface coatings that actually permeate old surfaces for tight, permanent bond that became more durable than the original surface.

I'm confident that there could become a way for "ferro" boat repairs to arrive at a permanent repair method.
 
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