# brass boiler/tube problem



## lotsasteam (Jan 3, 2008)

http://www.buntbahn.de/modellbau/viewtopic.php?t=10251

pictures talk:after 13 years of running the burner tube contracted and cracket the silversoldered seam!!

Manfred


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## JEFF RUNGE (Jan 2, 2008)

I think thats one reason most use copper.


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## Taperpin (Jan 6, 2008)

Manfred, 
our Australian Boiler code stipulates all copper ,with bronze or copper bushings, brass is not allowable ..the only boiler failures I have seen over many years have been in Brass tubes/plates and bushings etc..some where old boilers but a few where only 2or 3 years in service. 

Gordon Watson.


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## zubi (May 14, 2009)

That looks scary... brass boilers should be illegal at public steamups, well, in most countries with regulations on model steam power, they actually are! Best wishes from Tokyo, Zubi


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## xo18thfa (Jan 2, 2008)

The Australian Miniature Boiler Safety Committee (AMBSC) Code, Part 3, Sub-Miniature Boilers, paragraphs 2.3.4, allow brass boilers for low pressure, not to exceed 29PSI. Paragraph 2.3.5 allows soft solder construction low pressure boilers. Copper and silver solder are preferred, but brass and soft solder are allowed FOR LOW PRESSURE UNDER 29PSI


You could, as a quick fix to run the engine, repair it with soft solder, but not run over 29 PSI. Hydro test the repair to 58PSI. Long term fix and the right thing to do, have a new boiler made, code compliant.


It's not a complicated boiler. A new one is not hard to do. Use the old one as a template.


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## HMeinhold (Jan 2, 2008)

Bob, 
Thomas (the guy who started the thread in buntbahn) already began a replacement in copper. He dissected the boiler to find the root cause of the failure. I think it is the old brass story. If you get the wrong material and don't treat it correctly, it will get brittle and fails. We all agree that copper is the way to go. In Germany some people are still based on the old Carette/Maerklin brass boiler history. 
Regards


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## xo18thfa (Jan 2, 2008)

Fire, ready, aim. I should read the whole story first.

Brass and soft solder will make a fine low pressure boiler. But copper and silver is clearly better.


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## zubi (May 14, 2009)

Bob, the locomotive in question would not even move at 29psi (actually most of them did not move at any pressure...). This Mallet and essentially all other miniature live steam locomotives are intended to operate at pressures up to 60psi and should withstand at least twice as much. Brass is OK for a pop-pop boat boiler, but not for a live steamer where pressure under *normal* operational conditions can easily go up to twice the limit set by AMBSC code. Plus the same code (7.5.1) states that the brass boiler certificate is only valid for **one** year. I wonder whether all brass boiler owners get their vessels tested in time before the steamups... The scary part is, essentially all live steamers run on elevated trucks, at the eyesight level of children and often their mum's - watching our locomotives passing by. It is not only irresponsible to run a corroded brass sieve under pressure in front of their faces, it is also illegal (or should be). Best wishes from Tokyo, Zubi


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## xo18thfa (Jan 2, 2008)

I do not intend to build brass boilers. Ever.


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## Charles (Jan 2, 2008)

Posted By zubi on 06 Jun 2011 07:19 PM 
Bob, the locomotive in question would not even move at 29psi (actually most of them did not move at any pressure...). This Mallet and essentially all other miniature live steam locomotives are intended to operate at pressures up to 60psi and should withstand at least twice as much. Brass is OK for a pop-pop boat boiler, but not for a live steamer where pressure under *normal* operational conditions can easily go up to twice the limit set by AMBSC code. Plus the same code (7.5.1) states that the brass boiler certificate is only valid for **one** year. I wonder whether all brass boiler owners get their vessels tested in time before the steamups... The scary part is, essentially all live steamers run on elevated trucks, at the eyesight level of children and often their mum's - watching our locomotives passing by. It is not only irresponsible to run a corroded brass sieve under pressure in front of their faces, it is also illegal (or should be). Best wishes from Tokyo, Zubi 
"Brass is OK for a pop-pop boat boiler, but not for a live steamer where pressure under *normal* operational conditions can easily go up to twice the limit set by AMBSC code."

I am not certain I understand how brass boilers utilized in boats at pressures up to 60 PSI are so much different than our steam locomotive in quality and capacity for steam power regarding safety. I fully understand that cooper is a better material for boilers. A cooper boiler is what we install in our locomotive retrofits. Yet, there is a difference between early on brass with soft solder boilers and silver soldered Saito brass boilers that are sold worldwide (including UK, Australia, Japan and US). Having had the experience of many years operating steam boats utilizing about a dozen Saito boilers and engines at yearly events along with using a Saito boiler/engine as a stationary test unit for steam locomotive checks therefore I feel comfortable recommending such proper designed brass boiler as Saito.


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## TonyW (Jul 5, 2009)

Many early (pre-1990) Roundhouse locos have brass boilers.


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## iceclimber (Aug 8, 2010)

@import url(http://www.mylargescale.com/Provide...ad.ashx?type=style&file=SyntaxHighlighter.css);@import url(/providers/htmleditorproviders/cehtmleditorprovider/dnngeneral.css); Posted By TonyW on 14 Jun 2011 12:29 PM 
Many early (pre-1990) Roundhouse locos have brass boilers. 
pre-1990 being the point.


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## zubi (May 14, 2009)

Jeremiah and Tony, our understanding of quite a few things has changed since pre-1990s, for one example, many pre-1990 buildings contain asbestos (in the US, EPA issued a ban on asbestos in 1989, although this is not a full ban, some other countries have full ban but often introduced much later, for example in Japan it was legal to use asbestos until 2004). Is it safe to live in a pre-1990 building containing asbestos? Opinions may vary, just as they vary about using an untested old brass boiler at 60psi... 
Charles, pop-pop boats use an open system boiler/engine, do not develop any substantial pressure http://en.wikipedia.org/wiki/Pop_pop_boat I would advise against using brass for high pressure boilers for marine applications too, there is no difference. Saito boilers should be considered history, serve well as collectors items, look good when polished. Best wishes from Tokyo, Zubi


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## Charles (Jan 2, 2008)

Zubi
Saito boilers normal pressure range during running is between 30-45 psi. This discussion must define that with quality of build, proper operational pressure and performance design brass boilers are capable of being safe steam vessels. Companies like Mamod, Saito, Jensen, DR Mercer, Wilesco, SteamCo have long history and proven record of steam engines that function well with brass boilers. Yes, things improve and cooper boilers are better than brass but.... a picture is worth thousand words 


Diamondhead Statue to Mamod


One of the first public displays of steam I saw at the PRR Museum was a Mamod demonstration of steam locomotive (it was not new and had many hours of running).


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