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post #631 of 2951 Old 07-15-2015
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Re: Steel vs Fiberglass

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Originally Posted by Brent Swain View Post
Using 3/16th plate gives one a much greater margin of error in paint screw ups, . I have seen many boats lost to corrosion, which would have been usable for decades longer, had they had 3/16th plate.
I did not realize that you were using 3/16" plate. I had thought that you had previously said that you were using 1/4" plate. Charlie's 30-35 foot boats would have had 3/16" plating as well.

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Originally Posted by Brent Swain View Post
Mine comes pre shot blasted and zinc primed from the steel supplier, eliminating mill scale behind longitudinals and other " inaccessible to sandblasting" places. I put far more than mere primer inside, preferring a good buildup of epoxy on top of the zinc primer..
Charlie's standard spec of the era had the steel abraded and a zinc rich primer applied to protect it during transport and fabrication. Once the welding was completed, the steel was blasted back to raw steel and then coated with several coats of a zinc rich epoxy. It sounds like the only difference is that you painted the epoxy over the shop primer. I am surprised that worked since most epoxy coatings of the era were incompatible with the conventional zinc rich primers of the era.

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Originally Posted by Brent Swain View Post
Steel is exponentially stronger than other materials, in fact many times the strength to weight ratio. It is many times safer to go to sea in than other materials..
The section that I placed in bold is a mistake that you frequently make. While it is true that there is no doubt that steel is stronger on a per square inch of area unit basis, you have been shown that the contrary is true numerous times with detailed calculations in prior discussions on this topic. Because steel is so dense when compared to other modern boat building materials, with the exception of ferrocement, there is no modern boat building material that is weaker than steel on a pound for pound basis (especially when compared as a completed hull complete internal framing system) in all categories [bending, sheer (including impact resistance), and especially stiffness] but with the exception of abrasion resistance in which steel does very well for its weight.

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Originally Posted by Brent Swain View Post
Foam to the waterline is inadequate. In these cold latitudes, foam to the bilge makes a boat the most comfortable home you will ever live in.
Most of Charlie's boats were not designed for the far northern climates, and the decision was made to keep the bilges clear of insulation to permit inspections, and out of concerns for the foam to support mildew or trap materials that might erode the foam that were spilled into the bilge (such as engine oil) by mistake.

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Originally Posted by Brent Swain View Post
However, boats which need plating replaced after only 25 years, are not exactly the epitome of quality building. Far from it.
My point was that those boats that needed plate replacements may not be the epitome of durability, but they represent the state of the art in the early 1980's rust protection and so would be expected to be closer to the norm than the exception. Your claims for your building techniques may exceed those of these boats in question, but your boats represent a minority of the steel boats that were constructed during this era, and since this thread is discussing steel boats and glass boats in a general way, I suggest that the the norm is what it is.

Jeff
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post #632 of 2951 Old 07-15-2015
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Re: Steel vs Fiberglass

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Originally Posted by Jeff_H View Post
I did not realize that you were using 3/16" plate. I had thought that you had previously said that you were using 1/4" plate. Charlie's 30-35 foot boats would have had 3/16" plating as well.



Charlie's standard spec of the era had the steel abraded and a zinc rich primer applied to protect it during transport and fabrication. Once the welding was completed, the steel was blasted back to raw steel and then coated with several coats of a zinc rich epoxy. It sounds like the only difference is that you painted the epoxy over the shop primer. I am surprised that worked since most epoxy coatings of the era were incompatible with the conventional zinc rich primers of the era.
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Mine came with carboweld zinc rich primer , which was 85% zinc by weight dry film. Some came with international blue or red vinyl primer which nothing would stick to. After 31 years the epoxy over carboweld is 99% as good as the day I put it on 31 years ago.
I cant see the point in paying to shot blast and prime steel with the wrong primer ,then have to do it all over again to get the right primer on.
Using the right primer in the first place seems the intelligent thing to do.
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The section that I placed in bold is a mistake that you frequently make. While it is true that there is no doubt that steel is stronger on a per square inch of area unit basis, you have been shown that the contrary is true numerous times with detailed calculations in prior discussions on this topic. Because steel is so dense when compared to other modern boat building materials, with the exception of ferrocement, there is no modern boat building material that is weaker than steel on a pound for pound basis (especially when compared as a completed hull complete internal framing system) in all categories [bending, sheer (including impact resistance), and especially stiffness] but with the exception of abrasion resistance in which steel does very well for its weight.
------------------------------------------------------------------------------------
Steel has a compression and tensile strength of 60,000 PSI, Douglas fir 1500 PSI 1/4 inc steel plate at 10 lbs per sq ft has a tensile strength of 15,000 PSI , 10 lbs per sq ft fir has a tensile strength of 500 PSI
For a given weight, steel has 3 times the tensile strength of douglas fir.
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Most of Charlie's boats were not designed for the far northern climates, and the decision was made to keep the bilges clear of insulation to permit inspections, and out of concerns for the foam to support mildew or trap materials that might erode the foam that were spilled into the bilge (such as engine oil) by mistake.

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A good web in front of the engine stops oil from going any further forward. In 31 years I have had no such problems. On my last boat, lack of insulation under the bunks was far more trouble.
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My point was that those boats that needed plate replacements may not be the epitome of durability, but they represent the state of the art in the early 1980's rust protection and so would be expected to be closer to the norm than the exception. Your claims for your building techniques may exceed those of these boats in question, but your boats represent a minority of the steel boats that were constructed during this era, and since this thread is discussing steel boats and glass boats in a general way, I suggest that the the norm is what it is.

Jeff
=

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My boat was state of the art in the early 80s and I have had none of the problems you describe. Thus ,what was used on the boats you describe, was obviously not state of the art.

3/16th inch plate has a tensile and compression strength of 11250 lbs per linear inch. To get that kind of tensile strength out of Douglas fir ( at 1500 lbs PSI ) would take 7 1/2 inches of Douglas fir. As fir only has strength in one direction only, along the grain ,( with very little strength across the grain) that would be in one direction only ,whereas steel has the same strength in all directions. Even in triple laminated cold molded hulls, you would have that strength on only one layer, in one direction only, a third of the hull thickness , 2/3rds would be across the grain.Chain plate loads would all be across the grain of all three layers..
That is why a rifle bullet which can barely make it thru 3/8th inch steel plate, can go thru 23 inches of Douglas fir. Impact is impact, the same as a sharp rock, or a collision with something sharp.
Can you post pictures of huge oil tankers and cruise ships ,which were built out of wood, for its supposedly superior strength to weigh ratio?
The law of mechanical similitude makes wood impractical for any boats over a certain size, due to wood's lack of strength to weight ratio.
Strength to weight ratio is critical in the aero space industry. So when was the last time they used wood in commercial air liners or space craft?
There is no way of putting a wooden boat together with the 100 % strength of welding a steel one together. Most wooden boats rely on metal fastenings, and their friction with the wood around them, , basically held together by friction. There is no comparison between friction between wood and a metal fastening, in soft wood, and the 100% strength of a good weld, at 60,000 PSI tensile strength, or more.
My boats have hit at hull speed, rocks and steel barges with no serious damage. How many wood or plastic boats could survive such an impact. Most would suffer extreme damage. When reality contradicts theory, it is your theory which is clearly wrong. Calling reality 'Anecdote" to try undermine it's validity is to mislead, or to self deceive.

I have posted this before, so Jeff why don't you copy and paste it into your files, so you can re- read it any time you forget these facts? Saves me having to keep repeating it.

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Re: Steel vs Fiberglass

When the norm is to screwup, you dont blame the material for the screwups.
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post #634 of 2951 Old 07-16-2015
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Re: Steel vs Fiberglass

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Originally Posted by Jeff_H View Post
...................
My point was that those boats that needed plate replacements may not be the epitome of durability, but they represent the state of the art in the early 1980's rust protection and so would be expected to be closer to the norm than the exception. Your claims for your building techniques may exceed those of these boats in question, but your boats represent a minority of the steel boats that were constructed during this era, and since this thread is discussing steel boats and glass boats in a general way, I suggest that the the norm is what it is.

Jeff
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I had a client 4 years ago who wanted his steel Wittholz altered below the waterline, I designed a fin keel and balanced double hung rudder to replace the shoal draft full keel and transom hung rudder.
That hull was pretty much pristine after 30 years, the bilges had been kept dry and the paint inside the lower hull had been touched up every 10 years or so. It is possible to keep a steel hull in good condition.

Rust is a great motivator for maintenance, it builds up thick unsightly scabs that are in a ratio of 3 moles of oxygen to two moles of iron. Rust scale is not very dense and produces a thick scab of unsightly oxide long before it's a structural issue. That oxide also stains visibly.
Steel boats have been poorly built, especially the production boats from Europe have given the material a bad name in the USA. But in other parts of the world there are many steel boats that are in great shape. They just need to be constructed with internal access and well designed limber holes in framing and that was lacking in many commercial builds.

I've sailed on all hull materials now and cannot say there was much difference in overall maintenance providing it was well built and then looked after to start with. Wood was the worst GRP and steel about equal and ferro cement the best. Alloy is on a sliding scale, it can be hard to keep paint on and it can corrode very rapidly with little warning in both acid and alkaline conditions.

I have a steel cruising boat. I can afford whatever I want and I still prefer steel over other materials, my chosen style of cruising demands a strong forgiving boat (and I only have 3rd party insurance these days).
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post #635 of 2951 Old 07-17-2015
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Re: Steel vs Fiberglass

Rust shows itself in a bulge in the paint. Dry rot is hidden until it has done far more damage.
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Re: Steel vs Fiberglass

Both of those reasons are why fiberglass is a superior material.
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post #637 of 2951 Old 07-18-2015
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Re: Steel vs Fiberglass

I'm back!

I really don't care what BS thinks. I do care when he personally attacks my family, the mark of a very little man. I'm still waiting for an explanation of that ridiculous episode. But our worlds never collide. I never see his boats. I don't think I have ever seen one. He can run around with his knickers in a twist and type all day but I have my work to do. I have no desire to retire at all. I have my best work ahead of me.

North Carolina was hot and humid. I got the chance to spend two, very full days at the yard with my client and play some good Southern music with the crew at night. All in all a good time. Met three times with a new client for a center cockpit PSC 63. We'll see where that goes. I'd prefer to work on the west coast.

This photo shows the aft cockpit, remember, there are two cockpits on this boat, with the winches mounted. The pilot house windows are in an waiting for their stainless steel trim rings to cover the black bedding.

This shot shows looking down from the aft cockpit into the owner's stateroom with its walnut cabinetry.

Here is a pic of the engine room with the sea chest finished.

There is quite a bit of work left to be done. Most of our time at the yard was spent with mock ups for the drop leaf table and finalizing the placement of deck hardware for a rig capable of flying six sails at once. I predict another 6 months before the boat is launched.

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Re: Steel vs Fiberglass

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I'm back!

North Carolina was hot and humid. I got the chance to spend two, very full days at the yard with my client and play some good Southern music with the crew at night. All in all a good time. Met three times with a new client for a center cockpit PSC 63. We'll see where that goes. I'd prefer to work on the west coast.
Beautiful work as always, both the design and execution. Any chance you could persuade Pacific Seacraft to move back to the west coast? You know; the lower humidity yields a much better hull, that sort of thing.
I'm not just saying this because I might need some work done for my Orion.

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Re: Steel vs Fiberglass

Goat:
They are doing quite a bit of "refurbishing" now. There was one new boat ready to ship out and one refurbished boat ready to go. They look like new boats. Can't see them leaving NC though. It's hardly convenient for me. The flight there takes all day and I arrive at the B&B at midnight, their time. My client generously always flies me and my right hand man first class so it's not as bad as it could be. We have a good time. Costa Mesa would suit me better. But I'd miss the BBQ and the music sessions.

Here is a photo of the "medicine chest" as the Aussies call it. We call it the "bar".
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Re: Steel vs Fiberglass

I cant think of anywhere else on the planet I'd rather be right now than on the west coast.
Its been a super warm and windy summer, starting in April, after a super warm, dry, sunny winter here.
Was thinking of going to Cuba,to warm up, but didn't have to.

Some steel boats can be a nightmare to maintain, others are very little maintenance. Using stainless trim on all outside corners, and all hard to reach spots, like mast tablernackles, etc, and designing out nooks and crannies, can reduce maintenance by up to 80%. A good, super thick buildup of epoxy on clean, sandblasted steel, inside and out, can reduce maintenance to minimal . If you are having a problem with your paint, blast to clean metal, and do a super heavy buildup of epoxy, and maintenance can be drastically reduced for many years. If you are using a boat full time , in hard use , unlike plastic or wooden boats, welded down gear never works loose or leaks , which can make maintenance on a steel boat less than a plastic boat, and far less than on a wooden boat .
I once met a guy with a Steel Matangi motorsailer in Nelson New Zealand, who had owned wooden boats most of his life. He was amazed at how little maintenance his steel boat required , compared to his wooden boats

I was just told that Michael Kasten admitted that he didn't have the huevos to show up at the metal boat society's annual gathering, if there was a chance that I could show up. That is an open admission that what he has been saying about my boats, couldn't survive an open debate, with a level playing field. He prefers one sided postings, with no chance of a response.
I was also told that members there ,love my posts.
One should bear in mind, when reading posts on BD.net, that when I asked them about their metal boat cruising experience , only one said he had any, and only very limited coast cruising experience at that. The rest had none. One considered himself a metal boat expert, because he had welded up a lot of steel fence posts. Others cruising experience was about equal to that.
I just heard another one of my 36 footers is on the home run from Hawaii, finishing another trouble free circumnavigation

Last edited by Brent Swain; 07-18-2015 at 08:05 PM.
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