Steel Boat Coating

[Altair]

I am planning to have my hull blasted to remove badly adhering copperbot type anti-fouling put on by a previous owner. Being new to steel, I would welcome advice on maintenance, particularly the following;
Should I immediately apply a sealant to the bare metal so that I can wait to epoxy under optimum conditions: if so, what type of sealant?
Is coal-tar the most appropriate epoxy for the bottom, any suggestions on a brand?
Any recommendations for a blast cleaning firm in the NW.

All comments greatly appreciated.

 

[PaulJ]

I have used Jotun's "Jotamastic 87" system which came very highly recommended but my boat hasn't been launched yet so I can't speak from a position of long experience. The system consists of a first coat onto the bare steel of "Jotamastic 87 Aluminium" followed by one or more coats of the coloured Jotamastic to a total film thicknes if whatever it was....? I did a fair bit of homework before deciding on Jotun and it was recommended by a number of people - it was developed for use on the North Sea oil rigs and I'm told it is also used in the tanks of large tankers and it had the highest percentage of solids (87%) of any of the competition at that time. There are also a couple of websites specific to metal boats where you might like to ask your question...... www.metalboatsociety.com and the "Metal Boat" discussion forum on www.boatbuilding.com

 

[Guest]

Talk to a couple of blast cleaning companies as I am certain that there is a set of well defined rules about the time allowed before the steel is overcoated with some form of protection. I think it is as low as a couple of hours! - I guess the dryness of the atmosphere would have something to do with it ie humidity etc.

PZ

 

[PaulJ]

I would agree with that - a friend of mine who is building his own steel boat, has bought his own blasting machine (with the intention of selling it again when he has finished) and he is doing the job in sections, each day doing only as much as he can blast, clean up and coat in a couple of hours.....

 

[mtb]

Re: pds dogsthorpe

Peterborough they have the jotun range and the fella there has a wealth of tec information .
They advertise under coatings inthe magazine

Cheers
Mick

http://homepage.ntlworld.com/boats
I want a big steel ex trawler / tug v / cheap or swap for tug

 

[richardandtracy]

In General Engineering it's reckoned that the coating should go on within 4 hours when working indoors to get the best possible adhesion for the coating. Yachts don't use a different different grade of steel from anybody else - so shouldn't be treated any different.

It is possible to use a wax/oil finish instead of paint which is OK for a few days. But... how will you get it off a yacht?