Stainless steel chimney.

A friend had a stainless chimney made for his boat.

It looked terrific, but he said it didn't last any longer.

I think the only way to make a chimney last is don't use it in winter.

But seeing as you're a live aboard you're goosed

I've taken to using a a chimney liner, a few inches taller than a single skin chimney.

I stuff the gap with good quality silver foil (I see Nick uses expanding foam, I have thought of that but not tried it so far).

This has kept the boat clean for us for three winters, as the external part of the chimney is just ornamental. I suspect it will disintegrate when I remove it this summer, but it was only £29.

Rog

Having foamed ours, it’s lasting much better but of course we are only part-time users. I also changed where I store it when not in use, used to be in a bow locker, rather damp and cold. Now we store it behind the stove itself so it dries out after use and stays dry.

The chimney generally doesn’t get very hot but is cheaply made and badly finished, so bearing in mind the corrosive condensate only corrodes exposed metal, I’m wondering if a decent coating of some quality thick paint (on the inside, on a new one) would keep the corrosion at bay. Even if it does get fairly hot at times, there is plenty of high temperature paint out there (for eg motorbike exhausts).

316 stainless for the liner. 304 is probably OK for the outer bit but ideally the whole thing should be 316.

That's as I understand it anyway. Its all very technical and related to austenitic and martensitic stainless.

The sad truth is that not all stainless is stainless. Its a bit of a fraud situation.

Nobody claims its stain free....

These chimneys that you find in chandlers these days are Made in China - and you can't figure out why they fall to pieces after a year??!!

From The Daily TELEGRAPH - so it must be true!

Why 'Made in China’ is a mark of shame
They say that the first step on the road to recovery is to admit you have a problem. Only now, as the public becomes aware that the "Made in China" label is tainted with a huge number of shoddy and dangerous products, are companies beginning to understand there is a serious problem. The next step is to ask: why do Chinese manufacturers behave so badly?

The nature of the relationship between Chinese suppliers and Western importers is the key to the problem. Chinese factories are typically paid for their wares before they are shipped, so they have every reason to cut a corner or two.

Only after the containers have arrived at their destination are problems uncovered, and taking Chinese factories to court is not an option because of China's underdeveloped legal system.

Chinese manufacturers will do whatever they need to in order to catch a piece of business, but from there, the relationship often goes downhill, albeit in small steps. "Quality fade", the quiet and incremental degradation of a product's quality over time, is one of the more common issues.

Because Chinese manufacturers know that they cannot be matched anywhere else, and also that their Western customers prefer continuity in their supply chain, they feel comfortable nibbling away at quality levels, despite whatever contracts they may have signed. Product failures are, in effect, the result of a game that is being played and lost by Western companies in China.

Much of the problem is cultural. Chinese suppliers believe that what an importer doesn't know can't hurt him. They change product specifications without asking, and they believe that it is better to beg forgiveness than to ask permission. Quality is seen as a barrier to greater profitability and quality issues are not openly discussed.

Some believe that at the root of the problem is the political system. There is a carrot in China without a counterbalancing stick. China's Communist Party rewards manufacturers that help bring foreign currency into the country through commerce. At the same time, however, there is little or no punishment meted out to those who conduct their businesses in an unethical fashion.

Damn, I've just bought one from Lime Kiln chandlers but at least I know where to go when that one rots through.