Rusty Galvanised fittings

[lesweeks]

I'm gradually removing everything from the 1912 yawl I'm restoring and whilst 'sorting out' the bowsprit and bumkin I've removed the cranse irons which are a bit rusty in places. There are other fittings around the boat in a similar (and worse) condition - on the mast, gaff etc. - and I don't know how best to deal with them. Any suggestions?

 

[Bajansailor]

I suppose the best thing to do would be to renew the hot dip galvanising - but that is bound to be expensive.

Alternatively, you could look at cleaning up the rusty areas, and then using a zinc rich (also sometimes called 'cold galvanising') paint like Galvafroid (sp?) lavishly over the affected areas.

 

[oldharry]

Go for the hot dip galvanising, and forget it for another 96 years. Galvafroid unfortunately is quite soft so does not wear well, and you will have a regular maintenance job.

 

[ccscott49]

Re-galvanising is the only real effective way and is not expensive. Have a look in yellow pages for galvanisers, some of the midlands area ones, will put your small batch through with an industrial load, which makes it very cheap. Especially if you ge-grease it, clean and deliver collect it, a chat with the foreman often helps!! Try these guys first, not the port area, boat ones, who do like to rip off the unfortunate yachtie!

 

[flyingjunior]

Have a work with your local blacksmith as quite often they stick smaller orders through all together to get through the minimum order charge (HWMBO's local galvenisers have a minimum order charge of £50) and thus makes it cheaper for the client.

 

[Peterduck]

Having been there and done that, I can tell you that the greatest part of the work is getting these fittings free of the boat, so that you can do something with them. If you don't remove the rust completely, you will never stop working on it, because it will never stop growing while you're not there. You'll have to get used to the idea that restoring a lovely old boat takes money; lots of money. T.L.C. stands for Time, Labour and Cash, and boats absorb huge amounts of all of these. By all means try to get your fittings included with a larger order, but do not settle for less than complete re-galvanising. There is one exception; galvanised bottle screws. Re-galvanising will fill the threads with zinc, and you won't believe the trouble that you will have getting the zinc out of them again, especially the left-hand threads. The only recourse with bottle screws is to replace them.
Peter.

 

[fisherman]

[ QUOTE ]
The only recourse with bottle screws is to replace them.
Peter.

[/ QUOTE ]

Not quite: I would mask the thread and have them zinc sprayed. A lot of hot dip galvanising on my boat has failed and been replaced by shotblasting and zinc spray followed by two coats of (sprayed) primer. One item is a deck hauler cabinet, subject to sea water thrown off the pot ropes, and it may be that electrolysis took place. All the galvanising came off in a sheet. Zinc spray has lasted better and incidentally is a much better finish when painted. I have a suspicion that hot dip is not what it was.

 

[justdrifting]

i think thats true. Thats perhaps why presice dip has expanded it has hundreds of galva units for every possiable item.Never used it but looks really good

 

[lesweeks]

Thanks Guys.
I suspect that I'll go for a combination of approached depending on the individual fitting. Bottle screws?! Dead eyes and lashings on my old lady.

 

[BobPrell]

I have never had any lasting success with any brush-on rust neutralizers, followed by paint, whether zinc-enriched or not. Likewise with wire-brushing rust, it seems to just polish after a while, and driving the grinder is a filthy and frustrating task.

There is probably some sound environmental reason for not doing what I will describe. Nevertheless I have found it effective. Use precautions for handling toxic substances.

Leave the item in old battery acid overnight. The rust dissolves. You may be horrified at how much material goes. If it does, the fitting was seriously weakened anyway, and is not fit for further service.

Remove the fitting from acid, wash thoroughly with fresh water and heat gently to dry. Apply metal primer of choice. The dissolved rust leaves a terrific key for the paint. I believe this is what makes this method so effective.

The drawback of this method is that all surviving galvanizing gets dissolved by the acid even before the rust!

cheers