On Mon, 21 Feb 2005 21:50:56 +0100, "Steve Lusardi" <stevenospam@lusardi.de> wrote:
Condensation on the >inside is a whole different matter. There the best protection is urethane >foam above the water line and tar below.
Wish more people did that. I've seen steel hulls with everything below the cabin sole foamed in, and it seems to essentially trap moisture and makes a nice damp sponge...with predictable results.
Can you coal tar the entire interior hull and then foam waterline to hull joint? In other words, will ureathane foam stick to tarred steel? And is there any benefit to this?
Wilf Blanchard 21 February 2005 23:44:57 [ permanent link ]
David, Its the epoxy word thats significant. Coal Tar Epoxy is used to coat steel pipes and equipment in sewage treatment plants so you may gather it can withstand all sorts of acidic substances and has a long life. However, I don't know how it withstands the wear caused by rushing through water. I have no experience of that. Wilf
Here in Thailand it is widely used on steel boats and boats with cast iron keels ( our 42' ketch) lasts for many years especially when overcoated with anti-foul. Coal Tar Epoxy is as the name suggests - an epoxy.
Steve Lusardi 26 February 2005 13:57:56 [ permanent link ]
Yes, that is common practise. Keep in mind that epoxy paints work well if not exposed to sunlight. Very poor UV protection. Steve
"rhys" <rhys@nospam.com> wrote in message news:2sok1195kpmbaas1ip20avr70jqbj891o5@4ax.com...> On Mon, 21 Feb 2005 21:50:56 +0100, "Steve Lusardi"> <stevenospam@lusardi.de> wrote:>
Condensation on the>>inside is a whole different matter. There the best protection is urethane>>foam above the water line and tar below.>
Wish more people did that. I've seen steel hulls with everything below> the cabin sole foamed in, and it seems to essentially trap moisture> and makes a nice damp sponge...with predictable results.>
Can you coal tar the entire interior hull and then foam waterline to> hull joint? In other words, will ureathane foam stick to tarred steel?> And is there any benefit to this?>
Harry Krause 26 February 2005 18:53:50 [ permanent link ]
On Sun, 20 Feb 2005 20:51:04 -0500, gn48@mail.com wrote:
Hi,>
I'm considering buying a houseboat with a steel bottom. New steel>was put on 4 years ago, and treated with coal tar epoxy, supposedly.>I was told that the coal tar treatment will last for a long time. Can>anyone tell me if the coal tar treatment is really good for a long time,>like 30 years or something? If it is, then why doesn't everyone use>it? It it's not, then how long is it good for, what to do, and when, in >the future?>
Thanks for any help!>David
All my marinas (that I own) will do this work. I warrenty my coating for 20 years.
coal tar epoxy is unhealthy, 1970s type coating with all sorts of problems. Use instead modern coal tar equivalents that don't use coal tar as an epoxy additive
paul oman progressive epoxy polymers
Steve Lusardi wrote:
Yes, that is common practise. Keep in mind that epoxy paints work well if> not exposed to sunlight. Very poor UV protection.> Steve>
"rhys" <rhys@nospam.com> wrote in message> news:2sok1195kpmbaas1ip20avr70jqbj891o5@4ax.com...> > On Mon, 21 Feb 2005 21:50:56 +0100, "Steve Lusardi"> > <stevenospam@lusardi.de> wrote:> >
Condensation on the> >>inside is a whole different matter. There the best protection is urethane> >>foam above the water line and tar below.> >
Wish more people did that. I've seen steel hulls with everything below> > the cabin sole foamed in, and it seems to essentially trap moisture> > and makes a nice damp sponge...with predictable results.> >
Can you coal tar the entire interior hull and then foam waterline to> > hull joint? In other words, will ureathane foam stick to tarred steel?> > And is there any benefit to this?> >
R.
--
"Living on Earth is expensive, but it does include a free trip around the Sun every year."
i agree with steve that u should pay attention to the inside. 1. for the steel vessel, if the do the full blasting prior to painting, then the result is superior. dont forget the most important thing- blasting. after blasting u should paint the marine primer then undercoat and then coal tar expoxy and then to avoid marine growth, u should have the antifouling painted. 2. Usually boat owner will dock their vessel 2 to 3 years for inspection of the underwater hull and do some repair that have to be done during docking like inspection/repair of the seawater intake valve or strainer. u cant repair this item when the vessel is in the water. 3. coal tar expoxy in my experience is a very good paint and though there are many new paint at the market now but for me, if the price is reasonable, u still can use this paint. 4. if your vessel is stationary there, not moving very often where u will not scratch your underwater hull by those floating wood or rubbish, then the coal tar expoxy will last for many years but i am not sure it will last 30 years. if u do the blasting and follow the paint scheme, then the underwater hull really may last for many years. 5. In my country many boat owners like to use coal tar because it is cheaper then other new paint system. hope this will help.
