The oragami boat here used the rudder skeg as a keel cooler.

Has 25 gallons of antifreeze in the rudder skeg, just wonder if the
antifreeze is a good enough rust inhibitor and if the keel skeg will
radiate the heat well enough. If so... it sure beats the hell out of
having cooling channels or pipes coming out of the hull.

Joe

Joe wrote:
The oragami boat here used the rudder skeg as a keel cooler.


That is a good idea, but you don't even need to do that.
Just run parallel cooling lines (small diameter tubing works
best, but you have to make sure they will carry enough flow)
in metal-to-metal contact with the hull. The entire hull
will dissipate the heat.


Has 25 gallons of antifreeze in the rudder skeg, just wonder if the
antifreeze is a good enough rust inhibitor

Aluminum doesn't rust. Doesn't need an inhibitor.


... if the keel skeg will
radiate the heat well enough. If so... it sure beats the hell out of
having cooling channels or pipes coming out of the hull.


That's for boats made of wood or foam core or some other
insulator.

Another clever idea for a heat sink is to put a coil in each
thru-hull. Some refrigeration units have these as an option,
gets similar efficiency to water-cooling but you don't need
a pump.

DSK

DSK wrote:
Joe wrote:
The oragami boat here used the rudder skeg as a keel cooler.


That is a good idea, but you don't even need to do that.
Just run parallel cooling lines (small diameter tubing works
best, but you have to make sure they will carry enough flow)
in metal-to-metal contact with the hull. The entire hull
will dissipate the heat.

Are you saying run tubing inside the hull, but in contact with the
hull?
If so that would be a maintance nightmare.

One of the best features in the Oragami boats and the Strong All yachts
is the lack of framing. Framing is metals boats worst maintance
problem. You need proper limber holes and they all need to be kept
clean so any moisture will make it to the bildge and not be trapped and
develope frame pools. There were two spots on the hull of redcloud I
had to replace, and both were in the sail locker where water pooled
because it had no way to drain thanks to no limber holes up high. A
frameless boat is perfect. A copper nickle frameless hull 5MM thick
would last 300 years and never need painting.




Has 25 gallons of antifreeze in the rudder skeg, just wonder if the
antifreeze is a good enough rust inhibitor

Aluminum doesn't rust. Doesn't need an inhibitor.

His boat is steel and I guess he using anti freeze Glycol whatever...


... if the keel skeg will
radiate the heat well enough. If so... it sure beats the hell out of
having cooling channels or pipes coming out of the hull.


That's for boats made of wood or foam core or some other
insulator.

All the steel supply boats I ran (225-300fters) had keel coolers.
4"X2" steel channels about 100' long welded to the outside of the hull.
Simple and worked great.



Another clever idea for a heat sink is to put a coil in each
thru-hull. Some refrigeration units have these as an option,
gets similar efficiency to water-cooling but you don't need
a pump.

Just a coil before the exchanger to cool the feed water?

Joe

DSK

Joe wrote:
Are you saying run tubing inside the hull, but in contact with the
hull?
If so that would be a maintance nightmare.


Why? If you're worried about galvanic corrosion, use the
same material as the hull, put down a grid of half-round. To
prevent pockets & puddles, you could fair it over flat with
some cladding.

Or, since that would be a lot of work, just use tubing....
clad it into place with some material of low specific heat,
put insulation over it, and some zincs.


One of the best features in the Oragami boats and the Strong All yachts
is the lack of framing. Framing is metals boats worst maintance
problem.

Yep. Some of the Navy ships I worked on had frames that were
rusted all the way thru, right at the junction with the
hull... most noticable hull rust there, too. Shucks, the
first destroyer I was on had some big fiberglass patches in
the aft boiler room. We used to joke about not chipping too
much rust because that was all that was keeping the water out.


.... A copper nickle frameless hull 5MM thick
would last 300 years and never need painting.


But it would go thru a lot of zincs.


Aluminum doesn't rust. Doesn't need an inhibitor.


His boat is steel and I guess he using anti freeze Glycol whatever...


Ah so, I thought the Origami boats were aluminum.


All the steel supply boats I ran (225-300fters) had keel coolers.
4"X2" steel channels about 100' long welded to the outside of the hull.
Simple and worked great.


Yep... only problem is if you bang something against it, or
if it gets fouled up with barnacles etc etc.




Another clever idea for a heat sink is to put a coil in each
thru-hull. Some refrigeration units have these as an option,
gets similar efficiency to water-cooling but you don't need
a pump.


Just a coil before the exchanger to cool the feed water?


Condenser coil built into the thru hull. They're a little
more bulky than a regular thru hull.

Sure it dumps heat into the water coming in, but not very much.

DSK

DSK wrote:
Joe wrote:
Are you saying run tubing inside the hull, but in contact with the
hull?
If so that would be a maintance nightmare.


Why? If you're worried about galvanic corrosion, use the
same material as the hull, put down a grid of half-round. To
prevent pockets & puddles, you could fair it over flat with
some cladding.

Fairing componds suck on steel or any metail IMO. They hold moisture
and do not flex equal to the metal.

The issue is not galvanic corrision, but trapped moisture.

Or, since that would be a lot of work, just use tubing....
clad it into place with some material of low specific heat,
put insulation over it, and some zincs.

ugh....




One of the best features in the Oragami boats and the Strong All yachts
is the lack of framing. Framing is metals boats worst maintance
problem.

Yep. Some of the Navy ships I worked on had frames that were
rusted all the way thru, right at the junction with the
hull... most noticable hull rust there, too.

yelp..it's due to improper construction and maintaince. Any place
moisture can set on steel or be trapped is bad... I spend to much time
making sure all my limber holes drain properly and do not get
fouled..It would be a pleasure not having to deal with frames

Shucks, the
first destroyer I was on had some big fiberglass patches in
the aft boiler room. We used to joke about not chipping too
much rust because that was all that was keeping the water out.

I've worked a couple of boats that chipping hammers were banned.


.... A copper nickle frameless hull 5MM thick
would last 300 years and never need painting.


But it would go thru a lot of zincs.

No zincs needed.


Aluminum doesn't rust. Doesn't need an inhibitor.


His boat is steel and I guess he using anti freeze Glycol whatever...


Ah so, I thought the Origami boats were aluminum.

Most are steel.


All the steel supply boats I ran (225-300fters) had keel coolers.
4"X2" steel channels about 100' long welded to the outside of the hull.
Simple and worked great.


Yep... only problem is if you bang something against it, or
if it gets fouled up with barnacles etc etc.

Next to the keel they are protected. Inspected boats are in the yard
enough to deal with fouling.

Joe




Another clever idea for a heat sink is to put a coil in each
thru-hull. Some refrigeration units have these as an option,
gets similar efficiency to water-cooling but you don't need
a pump.


Just a coil before the exchanger to cool the feed water?


Condenser coil built into the thru hull. They're a little
more bulky than a regular thru hull.

Sure it dumps heat into the water coming in, but not very much.

DSK

... If you're worried about galvanic corrosion, use the
same material as the hull, put down a grid of half-round. To
prevent pockets & puddles, you could fair it over flat with
some cladding.


Joe wrote:
Fairing componds suck on steel or any metail IMO. They hold moisture
and do not flex equal to the metal.


True. But then, nothing's perfect (except carbon fiber, of
course).


The issue is not galvanic corrision, but trapped moisture.


That suggestion above was an idea of how best to reduce both.


One of the best features in the Oragami boats and the Strong All yachts
is the lack of framing. Framing is metals boats worst maintance
problem.


Yep. Some of the Navy ships I worked on had frames that were
rusted all the way thru, right at the junction with the
hull... most noticable hull rust there, too.


yelp..it's due to improper construction and maintaince.

Oh yeah, I'll be sure to tell the Navy exactly that, next
time I see them.




... Any place
moisture can set on steel or be trapped is bad...

Agreed

You mean, like on a boat




Yep... only problem is if you bang something against it, or
if it gets fouled up with barnacles etc etc.


Next to the keel they are protected. Inspected boats are in the yard
enough to deal with fouling.


Good point, but it doesn't come cheap. Also doesn't equal
1/10th the man hours deployed on steel hull maintenance by
the Navy.

DSK

DSK wrote:
Joe wrote:
Are you saying run tubing inside the hull, but in contact with the
hull?
If so that would be a maintance nightmare.


Why? If you're worried about galvanic corrosion, use the
same material as the hull, put down a grid of half-round. To
prevent pockets & puddles, you could fair it over flat with
some cladding.

Or, since that would be a lot of work, just use tubing....
clad it into place with some material of low specific heat,
put insulation over it, and some zincs.


One of the best features in the Oragami boats and the Strong All yachts
is the lack of framing. Framing is metals boats worst maintance
problem.

Yep. Some of the Navy ships I worked on had frames that were
rusted all the way thru, right at the junction with the
hull... most noticable hull rust there, too. Shucks, the
first destroyer I was on had some big fiberglass patches in
the aft boiler room. We used to joke about not chipping too
much rust because that was all that was keeping the water out.


.... A copper nickle frameless hull 5MM thick
would last 300 years and never need painting.


But it would go thru a lot of zincs.

Why?
Seems what I've read the copper boats are not zinc'd at all.


Aluminum doesn't rust. Doesn't need an inhibitor.


His boat is steel and I guess he using anti freeze Glycol whatever...


Ah so, I thought the Origami boats were aluminum.

So are, some are not, all are metal. Seems if I could find a scrap
copper nickle chem tank at one of the refineries around here it would
ake a great oragami hull. 1/2" thick Copper nickle:0)


All the steel supply boats I ran (225-300fters) had keel coolers.
4"X2" steel channels about 100' long welded to the outside of the hull.
Simple and worked great.


Yep... only problem is if you bang something against it, or
if it gets fouled up with barnacles etc etc.

They are close to the keel and protected against grounding.

Inspected boats hit the yard enough to deal with fouling.

Joe




Another clever idea for a heat sink is to put a coil in each
thru-hull. Some refrigeration units have these as an option,
gets similar efficiency to water-cooling but you don't need
a pump.


Just a coil before the exchanger to cool the feed water?


Condenser coil built into the thru hull. They're a little
more bulky than a regular thru hull.

Sure it dumps heat into the water coming in, but not very much.

DSK