Have you been in the containers?
50 foot is a nice size but fast approaching the need for crew.
It would be nicer if it had a full keel, not as critical since it is
steel.

When I bought RedCloud I wish it was a bare hull, took quite a while
to rip everything out and start over. Also it gives you the freedom to
design things to fit your needs.

First thing to do is blast the interior, make sure it has proper
limber holes and every drop of water drains with ease to the lowest
point of each WT compartment.

Then coat the steel with a nice 2 part epoxy.

I will be happy to walk you thru the next 100+ key steps .... if you
buy the boat.

Joe

"Capt.Mooron" wrote:

Heh Joe... an estate has a 55 ft high carbon steel

Why high carbon? So it will hold an edge better? Seems I'd rather have
the ductility.

Cheers
Marty

carbon steel
Iron alloy phases
Austenite (γ-iron; hard)
Bainite
Martensite
Cementite (iron carbide; Fe3C)
Ferrite (α-iron; soft)
Pearlite (88% ferrite, 12% cementite)


Types of Steel
Carbon steel (up to 2.1% carbon)
Stainless steel (alloy with chromium)
Surgical stainless steel
Chrome moly
Tool steel (very hard; heat-treated)


Other Iron-based materials
Cast iron (2.1% carbon)
Wrought iron (almost no carbon)
Ductile iron


Carbon steel is a metal alloy, a combination of two elements, iron and
carbon, where other elements are present in quantities too small to
affect the properties. Steel with a low carbon content has the same
properties as iron, soft but easily formed. As carbon content rises the
metal becomes harder and stronger but less ductile. Typical
compositions of carbon a

Mild steel 0.10% to 0.25% (e.g., AISI 1018 steel)
Medium carbon steel 0.25% to 0.45% (e.g., AISI 1040 steel)
High carbon steel 0.45% to 0.95%
Very high carbon steel 0.95% to 2.1%
Steel with sufficient carbon compositions can be heat-treated, allowing
parts to be fabricated in an easily-formable soft state then made
harder for structural applications. Steels are often wrought by
cold-working methods, which is the shaping of metal through deformation
at a low equilibrium or metastable temperature.


Metallurgy
Heat-treatment is an important aspect of carbon steel processing and
involves the hypoeutectoid reaction between almost pure iron
(α-ferrite), cementite (Fe3C), and austenite, which is a reorganized
FCC iron structure that exists only at high temperatures. Carbon has a
higher degree of solubility in the austenite phase. The rate at which
the steel is cooled through this eutectoid reaction affects the rate at
which carbon diffuses out of austenite. Cooling through a hypoeutectoid
reaction in carbon steels results in a mostly pearlitic arrangement of
alternating layers of ferrite and cementite.

Mild steel is the most common form of steel as its price is relatively
low while it provides material properties that are acceptable for many
applications. Mild steel has medium carbon contents (up to 0.3%) and is
therefore neither extremely brittle nor ductile. It is also often used
where large amounts of steel need to be formed, for example as
structural steel.

Carbon steels which can successfully undergo heat-treatment have a
carbon content in the range of 0.30% to 1.70% by weight. Trace
impurities of various other elements can have a significant effect on
the quality of the resulting steel. Trace amounts of sulfur in
particular make the steel red-short. Low alloy carbon steel, such as
A36 grade, contains about 0.08% sulfur and melts around 2600-2800 F
[1].


Heat Treatment

Iron-carbon phase diagram, showing the temperature and carbon ranges
for certain types of heat treatments.Full Annealing: Heating to a high
temperature then cooling slowly. Results in a soft and ductile steel
with no internal stresses, often necessary for cost-effective forming.
Normalizing: Heating to a high temperature then cooling at a medium
rate in a furnace. Results in steel that exhibits a good balance of
mechanical properties, by offering high strength and a good degree of
toughness
Hardening: Heating to high temperature then cooling rapidly in water or
brine. Also called quenching. Results in steel that is extremely strong
but brittle containing a high degree of internal stresses. Results in
formation of Martensite, a form of steel that possesses a
super-saturated carbon content in a deformed crystalline structure (BCT
- Body-Centered Tetragonal) with a high resistance to deformation but
with extremely high internal stresses. The technique requires steel
with a carbon content high enough to be hardenable.
Case hardening, flame hardening and induction hardening: Only the
exterior of the steel part is heated and quenched, creating a hard,
wear resistant skin, but preserving a tough interior. The surface of
the steel is heated to high temperature then cooling rapidly through
the use of localized heating mechanisms and water cooling. Typical uses
are for the shackle of a lock, where the outer layer is hardened to be
file resistant, and mechanical gears where hard gear mesh surfaces are
needed to maintain a long service life while toughness is required to
maintain durability and resistance to catastrophic failure. Case
hardening requires a steel with a certain level of carbon to be
effective. Low carbon steels may be case hardened only if additional
carbon is introduced:
Packing low carbon steel parts with a carbonaceous material and heating
for some time diffuses carbon into the outer layers. The parts then
respond to heat treatments as above. A heating period of a few hours
might form a high-carbon layer about one millimeter thick.
Carboration may also be accomplished with an acetylene torch set with a
fuel rich flame and heating and quenching repeatedly in a carbon rich
fluid (oil).
Spheroidizing: Heating to a high temperature (austenitic) then cooling
at an extremely slow rate through active temperature control. Results
in spherically diffused carbon areas with mostly iron rich
compositions, also known as spheroidite, as opposed to elongated bands
of pearlite. Results in extreme softness and ductility, often only
necessary when a high degree of forming is necessary.
Tempering: Reheating hardened steel to a lower temperature then
cooling. Reforms crystal structure for a combination of strength and
toughness depending on temperature. Necessary when a high degree of
internal stresses are present or after quenching when the material is
too brittle to be viable for structural applications. Actual
temperatures and times are carefully chosen for each composition.
A limitation of plain carbon steel is the very rapid rate of cooling
needed to produce hardening. In large pieces it is not possible to cool
the inside rapidly enough and so only the surfaces can be hardened.
This can be improved with the addition of other elements resulting in
alloy steel.

Joe wrote:

carbon steel blah blah...

I hope you read and understood it all, now back to the point: Why high
carbon steel for a hull?

Cheers
Marty

Stronger, harder, stronger.. Steel with sufficient carbon compositions
can be heat-treated, allowing
parts to be fabricated in an easily-formable soft state then made
harder for structural applications.
High Carbon steel rolls and holds it's shape nicely, and I suppose high
carbon slows rust too!
I've never seen a carbon anything rust.

Joe

There is no good reason for using high carbon steel in a yacht hull.

It's harder to weld.

The weld heat affected zone has different characteristics to the parent
material, usually worse, nearly always different corrosion
susceptibility.

High carbon steel has somewhat greater tensile strength, but so what.
Steel yacht hulls are massively overstrength anyway, the plate
thickness is set by the need for min thickness for corrosion allowance
over the life of the hull.

High carbon steels with heat treatment become brittle and can fail from
shock loads. Not that anyone in their right mind would do this WRT
boats.

High carbon steels do *not* roll and hold their shape nicely, WRT low
carbon steels, because they WORK HARDEN and if not annealed, become
brittle and develop stress cracks and fail.

High carbon steel does *not* slow rust appreciably. Some steel alloys
have greater corrosion resistance but this is due to the alloying
elements, not the carbon. In fact, very *low* carbon steel resists
corrosion better than high carbon steel.

Feel free to argue about it all you like. I'll just quote more bits
from 'The Procedure Handbook of Arc Welding' by the Lincoln Electric
Company.

You might own a steel boat, Joe, but so do I. Just that mine's bigger
than yours :-)

PDW

In article .com, Joe
wrote:

Stronger, harder, stronger.. Steel with sufficient carbon compositions
can be heat-treated, allowing
parts to be fabricated in an easily-formable soft state then made
harder for structural applications.
High Carbon steel rolls and holds it's shape nicely, and I suppose high
carbon slows rust too!
I've never seen a carbon anything rust.

Joe

Not trolling Joe. This is what this father and
son claim they did to mount their motor in their boat.

I didn't not climb in to check it, but I was quite amazed
and I don't think they were lying to me.

"Joe" wrote
Bad move Bart. You're trolling right?

Well it's a bad move all the way around. Vibration, stress,
electrolysis, ect..ect..ect...

Joe

Joe wrote:
Stronger, harder, stronger..

I think you're mistaken there. Higher carbon alloys are
stiffer, not stronger.

... Steel with sufficient carbon compositions
can be heat-treated

Yeah, great idea. A heat-treated boat... and the
advantage(s) of such??

.... allowing
parts to be fabricated in an easily-formable soft state then made
harder for structural applications.

"Hardness" is of no benefit in a structural application. And
I think "easily-formable" is relative.


High Carbon steel rolls and holds it's shape nicely, and I suppose high
carbon slows rust too!
I've never seen a carbon anything rust.


Ever looked?

Peter Wiley wrote:
There is no good reason for using high carbon steel in a yacht hull.


I can think of one... if you happened to have a lot of it
laying around in approximately the right size pieces.


It's harder to weld.

The weld heat affected zone has different characteristics to the parent
material, usually worse, nearly always different corrosion
susceptibility.


Yes, it changes the crystalline structure of the metal.


High carbon steel has somewhat greater tensile strength, but so what.

IIRC the biggest difference is a straighter yield curve,
maybe slightly stronger too. If high carbon steel were
really stronger in tension, they'd make cable from it.


Steel yacht hulls are massively overstrength anyway, the plate
thickness is set by the need for min thickness for corrosion allowance
over the life of the hull.


It's the best stuff if somebody is going to be shooting at
you, or you plan to bounce over a lot of rocks. Other than
that, the only reason I can think of to build a boat of less
than 20 tons (or so) out of steel is because you are already
a skilled metal worker and have a lot of supplies, and
really really like the concept of a bulletproof boat
(although it should be recognized that fiberglass can also
be bulletproof).

I wonder how well a boat would hold up if sprayed both sides
with that plastic pick-up truck bed liner material?


High carbon steel does *not* slow rust appreciably. Some steel alloys
have greater corrosion resistance but this is due to the alloying
elements, not the carbon. In fact, very *low* carbon steel resists
corrosion better than high carbon steel.


IIRC most stainless steels are very very low carbon.

OTOH there is a lot of truth in Joe's statements if you take
them to their logical conclusion and use the highest
carbon material... carbon fiber!


Feel free to argue about it all you like. I'll just quote more bits
from 'The Procedure Handbook of Arc Welding' by the Lincoln Electric
Company.

You might own a steel boat, Joe, but so do I. Just that mine's bigger
than yours :-)


Yeah but Joe lives in Texas. Everything looks much bigger there.

Fresh Breezes- Doug King

Heat Treating???

Well back in the old days there was this ol man who buildt many a 62
fter in his back yard on the Chesepeake Bay. All his hulls are fair and
hand nibbed using a rose torch and nibbing bars. Most sleek steel hulls
you have ever seen. The full keel curved to meet the fairest hull not a
square exposed weld on the hull. Seemed it was a hobby and he buildt
6-7 of em.

I used truckbed liner as non-skid. When exposed to hard traffic and UV
it becomes polished and slippery and needs re-coating in 3 yrs. I like
the stuff but it's expensive Like 400 for me do do a small path and
spot near the masts. I used Duraback(sp??) brand name. MIL Spec
approved non-skid now. On a new build inside any good epoxy is great if
properly applied! I do not like epoxy that is exposed to UV. It is
stronger and more chip resistant but fades , streaks and needs to be
re-coated more often than a good oil base. I use epoxy as a barrier
under the antifoulant. If I had a new bare hull Id met-coat the whole
thing inside and out. Thats spraying a molten hot zinc on. Thats how
they coat the offshore platforms before painting. It's the very best
for steel.

Joe