Steel VS Fiberglass trawlers

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jerry rogers

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As I am new to this forum and in the due diligence stage of research for a trawler, I have been chatting with a captain with vast experience including 3 circumnavigations. This gentleman is absolutely sold on steel boats. Would love to hear from other experienced boaters with pro and con views. We will do the loop in a few years and beyond that, maybe the Carribean? Looking at single engine*trawlers w/flybridge.
 
I agree on the steel hulls. Epoxy paint systems today make maint a breeze and corrosion a non issue. Don't shy away from fiberglass and only consider steel, the FG boats are much more available on the used market
and there is a wider choice of product. Both materials have there pros and cons.
 
As Sailor of Fortune stated "dont shy away from fiberglass and only consider steel". There are many advantages and disadvantages of both.
Generally speaking, fiberglass repairs are easier than steel repairs for most people. Steel has a corosion problem and fiberglass over a core such as on decks has a delamination problem. Both are repairable and some prefer fiberglass over welding - pick your choice. These are both avoidable, but, if s**t didn't happen, no one would use that expression.
When it comes to older boats, a neglected steel hull can have problems equal to or more devastating than FG. If you are looking in the used market see what comes up and DEFINITELY find a good surveyor.

Tony B
 
As noted, if steel is prepared correctly, the maintenance is minimal. *If *not prepped properly, entropy will prevail. *Having owned wood, fiberglass and steel, my experience is that steel is far less maintenance than wood, and about the same as fiberglass. *For world voyaging, there isn't much choice in my mind. *Steel prevails because of stength and simplicity of repairs, if needed. *Just my opinion.
 
Steel is the preferred material for grounding or pounding on rocks , reefs and beaches.

Much less of a problem today with a working GPS than a working Sextant and DR plot..

I am not convinced the new interior finishes are "forever", so if properly built the interior is removable so the hull can be blasted "water white" and the next 7 coats of whatever installed.

This with paint was a 15 year requirement , with epoxy it should be longer, but nothing is forever.

Remember too an external scratch MUST be attended to with a steel boat as rust holes go either way.

Steel does not burn, lots of GRP, (no FR, Fire Retardant) burns 500% faster than wood.

GRP with a good core , Airex , would be my first choice , although the usual cookie boat is not FR .
 
Jerry

Where would the boat be located? Moisture due cool climates can be a problem on metal boats.


-- Edited by sunchaser on Sunday 11th of September 2011 05:55:11 AM
 
Delfin wrote:
*Steel prevails because of stength and simplicity of repairs, if needed. *Just my opinion.
*In remote places you can find a welder or have one on board to make temporary repairs on a steel hull.* Not so easy with fiberglass.
 
I think soon, we may be looking at things like glass, steel, and many other materials as "cores". Coatings are becoming so durable that they, themselves, may be what we are purchasing in the future, cored by whatever. Molecular bonding of different materials have come a long way in these last two decades.
 
jerry rogers wrote:
......*with a captain with vast experience including 3 circumnavigations. This gentleman is absolutely sold on steel boats. Etc, Etc.
*As you pursue your due diligence I think you will soon discover that the compromises necessary in a boat capable of a circumnavigation may not be ideal for your intended purpose.* It is a cliche to say that any boat is a floating compromise but that most certainly is true and likely moreso if you purchase a used vessel.* As a recent purchaser my take on your situation is that you will eliminate a lot of very serviceable, well found boats that would suit your purpose if you insist on a steel vessel, particularly so in the under $200k market.
 
compromises necessary in a boat capable of a circumnavigation may not be ideal for your intended purpose.

Tanks inside take loads of room when you need 2000G of fuel instead of 200 for ditch crawling.

Ditto for water and food .

Due to the way boats grow , 40 fter is way smaller than a 50 fter , Bigger can be better.

IF its bigger and relativly skinnier bigger IS better.
 
Steel is the materail of choice for circumnavigations or cruising in remote areas where a welder could be found and fiberglass repairs would be difficult. I have run many steel boats, all commercial, such as passenger, supply, tugs, well built for tough service. For the Loop and maybe the Carribean you should have a much broader selection of boats to pick from if you include fiberglass.
 
Tucker

Steve Dashew, Northern Marine*and PAE would disagree that steel is the material of choice for world wide cruising in motor vessels below 75 or so feet.* Benetau, Swan, Hinckley*etc sail boats are certainly global vessels and not steel.

*
 
As noted, if steel is prepared correctly, the maintenance is minimal. *If *not prepped properly, entropy will prevail. *Having owned wood, fiberglass and steel, my experience is that steel is far less maintenance than wood, and about the same as fiberglass. *For world voyaging, there isn't much choice in my mind. *Steel prevails because of stength and simplicity of repairs, if needed. *Just my opinion.

I was looking around this forum for an existing subject thread dealing with STEEL HULLS. I think I found it here. At least there appears to be some level headed postings that don't just go off on a jaunt about how much trouble steel boats are to maintain. In fact I am surprised that this subject thread was not longer (more extensive), with all the naysayers that exist.

I'm seeking to utilize a steel hull construction on this Pilgrim trawler redesign....subject thread over HERE
Trawler Forum - View Single Post - Redesigning the Pilgrim 40 Trawler / Canal Boat

...but take notice, only the bottom shell portion of the hull, NOT the deck, nor the superstructure.

I'm new to steel hull construction and related topics as I come from the lt-weight multihull boat business. So I'm learning. But I have seen some steel boats that you could almost eat off of the bilges they were so clean, and I have read a number of accounts as to how much easier steel boats of today are to maintain, particularly if they were prepped correctly when they were first built.

I enter this subject thread hoping to learn more about these proper preparations, and the 'care and feeding' of steel hulls.

(PS: I chose not to start this discussion over on that 'redesign' subject thread, as I feared this particular aspect might get a life of its own and take over that other subject thread)
 
There is just something about steel....

I've been aboard every kind of vessel that there is, made of: Wood, Fiberglass, Cement, Composits, Aluminum, and yes steel. And there is something about steel that just seems to say it all; strength, seaworthiness, a sense of security, and durability (Especially in foul weather.) that the other hulls just don't inspire. Steel, And Fun Everyone is an acronim for Safe, and I think that explains how we all feel on a steel hulled vessel.

True, Aluminum comes close, but I always think of aluminum foil, and how it crinkles, and not that the space shuttle's 2" thick hull is made of aluminum. LOL

And fiberglass, well just having glass in the word is enough to unsettle a real swab.

And didn't they use to put cement goulashes on people like Jimmy Hoffa for a reason?

Now wood is okay for someone like Noah who had no idea of what steel was, as it hadn't been invented yet, and his boat wasn't being built for long term usage anyway, it just needed to float for a while. And too, polished wood is wonderful for a nautical setting inside of a steel boat too, to remind us of our roots.

And finally, composits are fine light weight material when used for building air, and spacecraft, but they cost too much, and are as yet untested by time, and really are no more than a space age form of fiberglass to me. And there's that word glass all over again. Geesh!

Now truthfully, when you measure your boat against another out in the water which one would you want to have under you when they collide in the fog?
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Capt John S. Keller
Great Lakes Pilot

...forgot where I found this quote, but thought it appropriate for this subject thread.
Brian
 
Steel Hull Prep and Maintenance

While looking thru a few 'steel hull discussions' I ran across these three references all on just this one page HERE: 4mm steel hull

Wynand N said:
Jim, If a hull & deck are properly shotblasted (dislike pre-blasted/primed plates) and epoxy coated, especially on the inside after building, there should be no problems as long as preventative maintenance is done, as is true with other materials as well. I uasually sprayed (airless) the inside with a coaltar epoxy with a minimum thickness of 180 microns after blasted to spec SA2.5.
Older boats, especially home builts were prone to rust, because very few were ever shotblasted in backyards. I've seen some guys using chemicals to remove rust prior to painting,others just wire brushing!! and some just touch up paint on welds etc on pre-primed plates. These are all guaranteed recipes for rust.
Remember, paint is only as good as its preparation. With modern knowhow and epoxy paints it is not neccessary to "build-in" the rust factor. In fact, a well built & epoxied coated steel boat will outlast any fibreglass one.

yago said:
Jim, I have reviewed boats I built over 20 years ago, 4 of my own building and several others built by friends in the same period. They had been all been shotblasted and covered with epoxy paint. Not a spot of rust inside, nothing at all.
On the outside they had a few spots on deck repainted, where the paint had worn off over the years but that was always on welded on eyebolts, cleats etc, fittings that should have been stainless anyway. Hull and Deck were spotless.
Properly blasted and painted, rust is no longer an issue, and certainly not something that you would want to increase plating for these days.

Wynand N said:
.... If your stringers are docked solidly against the plating and the welding sequence carried out as above, you will have no movement between plating and stringer to crack your expensive epoxy.
By the way, after shotblasting to an approx spec SA2.5 (white metal) we sprayed the inside with coal tar epoxy to a thickness of about 140 - 170 micron. Needless to say an airless spray unit was used to elliminate air trapped under paint, especially in corners. Our unit sprayed at about 220 bar pressure on nozzle.
 
....interesting excerpts from a steel boat builder/designer

MikeJohns said:
Epoxies really have made steel a low maintenance material in salt water. But inside and on decks as I said before hot zinc spray and then epoxy is the delux protection scheme.

MikeJohns said:
Some modern surface tolerant epoxy undercoats can cope with quite a moist surface and high humidity levels. But the real reason for heating steel prior to painting is the dew point. Heating steel evaporates surface moisture AND stops condensation in humid conditions when the steel temp is below the dew point.

MJ said:
The interesting thing about rust is that 2/3 of it comes from the atmosphere (one mole of iron and two moles of oxygen). So if the oxygen can get to it along with moisture it expands with a loose porous structure up to around 6 times the amount of actual corrosion. Chloride ions in sea water really accelerate the process.

When polyurea for example is used as a coating it doesn't stop the water reaching the steel, it stops the oxygen. Damaged coatings on metals like steel and Al alloy peel because the resulting oxide layer pushes the coating off in the interface where oxygen can get at it. On alloy it can peel at an amazing rate, on steel it's slow and very visible.

MJ said:
Bilges can stay pristine and on a steel craft . Just give them extra epoxy coats if you are worried. But again a hot zinc spray after sandblasting followed by a thick epoxy coating will see your bilges in pristine condition for the life of the vessel providing they are mostly dry, which they should be these days.

IMO a very good protective coating can be implemented simply with sika polyurethane sealant. We have applied approx 1/4 inch coatings of this to areas such as anchor lockers. Simply troweled on over a polyamide cure epoxy paint system. It protects the paint form chipping and has worked terrifically. But again you don't need to worry about chipping in the bilges I added this as folk should be aware that polyurea is not the only option and there are much cheaper and easier coatings that protect from impact very well.

MJ said:
Hot zinc spraying and then painted over the zinc with epoxy is a great coating system for the interior if you can afford it. Most steel boats I have worked with that were treated this way stay pretty much pristine inside. I have one 65 footer treated this way too.

But a steel craft should also be properly designed and constructed with a view to longevity. Hatch coamings for example should project through the steel decks amply.

If you just epoxy the inside well and keep the water out ( including condensation) you'll find it will outlast you anyway. As for the gaps between frames stringers and the hull, don't fret about them, for starters the paint goes into the gap and secondly these days we often use a bead of sikaflex polyurethane sealant to fill any gap. It works a treat and I can guarantee the sikaflex works we've been doing that for 15 years. We even use sikaflex underwater to seal riveted steel vessel plate boundaries after sandblasting.

I would use steel frames and I'd look for a design that can be built from flat plate. Looking at your design types you will have a lot of leeway for structural weight anyway.

A lot of successful steel craft have steel decks and plywood deck houses often that plywood is fiberglassed with a thin layer to completely weather proof the ply. A lot of earlier steel hulls have a deck shelf overlapped with plywood and then teak decks, there's a 1935 Dutch classic nearby that's still in great condition built this way.
 
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I would certainly consider steel if I was buying a new boat and I was confident in the company's quality control.

I wouldn't touch a home built steel boat with a shiny new paint job.

As with so many things - "It's all in the prep work"
 
As with so many things - "It's all in the prep work"

With steel the NA must be knowledgible enough to know how steel boats are built and maintained.

T or L stringers stand the skin loads just fine but are almost impossible to sand blast , even on an empty new hull.

For the refit without stripping the boat it is how most steel boats rust out , from the inside.

For dancing with uncharted reefs or heading North to burgy bit areas steel would be #1 choice.

For most cruising folks solid GRP from the WL down would be easier to live with.
 
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I'll add that most metal vessels continue the metal hull to the deck plating to a lip where the house is fastened....seems to ensure a leak free main deck.

I'm sure there are other "successful" ways...but not as common as the one described.
 
I worked on a steel ship for five years. I can tell you the exterior maintenance was never ending. Even though steel hulls are more rugged, I will never own one unless I win the lottery and can afford a team to maintain my boat.
 
..T or L stringers stand the skin loads just fine but are almost impossible to sand blast , even on an empty new hull.
You don't need T of L stringers on a pleasure boat....that's mostly for commercial and military constructions. Simply flat bar stringers are fine in most instances, and as MikeJohns pointed out on several occasions you need to fillet these with Sikaflex sealant and you are find. they have been doing this for 15 years. I doubt they would still be recommending it if it didn't work just fine.

"As for the gaps between frames stringers and the hull, don't fret about them, for starters the paint goes into the gap and secondly these days we often use a bead of sikaflex polyurethane sealant to fill any gap. It works a treat and I can guarantee the sikaflex works we've been doing that for 15 years. We even use sikaflex underwater to seal riveted steel vessel plate boundaries after sandblasting."


.... it is how most steel boats rust out , from the inside.
That's true. That's why I would want to pay particular attention to getting the prep right on the internals at the building stage.
 
I worked on a steel ship for five years. I can tell you the exterior maintenance was never ending. Even though steel hulls are more rugged, I will never own one unless I win the lottery and can afford a team to maintain my boat.
Define what kind of steel SHIP ??....a commercial boat, a Navy boat ??
 
I have been w a FG boat for 8 for eight years and have spent less than 3 days labor and probably $100 in materials maintaining the Hull. For the water under the bridge I don't think I could do much better.

But ther'e is worry about the plywood under the decks and in the cabin and plenty of vigilance is required to minimize the very real danger of serious problems.

Would I be better off w a steel hull? Not likely. But this is not a very useful discussion as ther'e are very few steel trawlers available. The discussion is mostly for new builds and then ther'e is the iffy question of who should build the steel boat.

I have seen steel boats built simply before epoxy was born that lasted for many years. And since epoxy they are much better than before so it would seem that a steel boat done right would obviously be a very sound and long lasting boat. Only an Airex foam or honeycomb cored FG boat could be better than steel ... As I see it.
 
The kind/price of boat I wanted wasn't available in FG, so steel was the default choice.
 
If you treat a steel boat like some people treat their fiberglass boats....street shoes off and boat slippers on...then I bet a steel boat's paint job will last.

Bet the paranoid tools make you take your belt buckles off too!!!!:socool:
 
I had a steel boat for 20 plus years. The problems I had were with marinas and boat yards that did not want steel boat customers. Parts suppliers who could only look up parts by manufacturer, model and year. Insurance company's who only insured boats that were listed in appraisal manuals.
 
Parts suppliers who could only look up parts by manufacturer, model and year. .

My experience is the same with FRP except no one ever asks what kind of vessel I have when I'm buying boat stuff. But I really don't care as all the systems are generic. FRP or steel don't care if Furuno, Racor, Torrid, Webasto or an Avon dinghy etc etc are hooked onto the vessel.
 
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