Ambitious project - model of Irrawaddy paddler "China" in 1 : 48 startet

[Hankwilliams]

Hi friends and neighbors,

may be, its quite interesting to show some historic photos of the Irrawaddy steamers.
Following pictures are from the book "The Irrawaddy flotilla company" by captain H.C. Chubb, London 1973.

Thomas

[Hankwilliams]

Boiler trouble!

Hi friends and neighbors,

sometimes also an old steam enthusiast and modelmaker must make the experience of failure.
The upper deck supports, stanchions and railings of the boat were finished.
So I made the flame tube boiler with copper flame tube and the outer brass boiler tube.
The pressure test of the flame tube was allright. For my pressure tests I fill the tube completely with water and gave heat. The pressure consists only in the expansion of the heatet water - a simple and effective method. As I wrote, the flame tube was obviously ok.
But when I tested the nearly complete boiler, one of the cross tubes was leaking in a strong way. I cut the boiler to reach and repair the flame tube and made a further test, which was allright. Later I soldered the two outer boiler parts with silver soldering together. But there rises a very small split between the material. It wasn`t possible to solder it steamtight, in spite of many attempts.
Now I must order a new boiler tube, the inner flame tube is tight and can be used again.
In the meantime I will continue with the upper deck.

Thomas

[Gerhardvienna]

Hi Thomas

Things can go wrong some times, I`m sure you will not fail the next attempt!

Regards
Gerhard

[Spankbucket]

Hope you didn't get tooooo steamed up about it!!! Lol.

Seriously though, this problem must have been really frustrating and patience testing!! You have my commiserations.

[steamboatmodel]

"So I made the flame tube boiler with copper flame tube and the outer brass boiler tube."
I don't know what the regulations are in Germany, but in most areas using brass in boiler construction is if not forbidden is very frowned on.
Regards,
Gerald.

[Hankwilliams]

Hi Gerald,

in Germany Messing (brass) 63 is allowed for boiler making. I prefer brass for the bigger parts, because it`s much more easy to solder.
My first boiler with outside brass tube and inside flame tube of copper I made in 1989 for the "Pilat" paddler, it`s still absolutely ok.
As I know, all Regner boilers are made completely of brass (Mr. Regner said one time, he wants to avoide different heat expansion thought different metals).
I know, that also here in Germany this is nearly a question of faith - brass or copper.
In fact, I`ve made 11 boilers since 1989 in this way and none of them gave a bad experience.

Regards

Thomas

[Brian Gates]

I am curious Thomas, do you use tap water in your boilers?  Here in Kent the water is so hard that the chalk deposits would protect the brass from dezincification, whilst in other parts of Britain it can be very soft and even acidic.

If I recall correctly, the situation in the UK is that boilers under 3 bar litres are exempt from the testing code and can be made from materials other than copper or welded steel.  I would guess however that Regner boilers, being CE marked, could be sold throughout the EU, regardless of whether club inspectors would be willing to carry out tests on them (I am pretty certain our local model engineering society inspectors would refuse).

Brian

[Hankwilliams]

I am using distillatet water normally. But I know some steam modellers who take the water of the rivers and lakes for boiler feed. They are cleaning the boiler from time to time like in locos.
As far I know, in the EU boilers below 2 litres capacity are except from testing - also bigger boilers with pressure below 0,5 bar. Nevertheless the material of   small boilers must be licensed. Licensed materials are steel, copper and brass 63 - but not another kind of brass, for example brass 58. Aluminium also is not licensed for a small or bigger boiler.
The discussion - copper or brass - in Germany is very hard. For my own, I must say that I`d never had bad experiences with brass boilers.

Thomas

[andy]

I constructed my boilers from inox steel and calcoulated according to TÜV regulations here in Germany. I do not want to get any risk.

http://picasaweb.google.com/a.heene/KesselSchondorf

So I could avoid too muc weight because all the materials could be choosen thinner.

Andreas

[Hankwilliams]

Hi Andy,

I know your very fine boats, engines and boilers. We met some years ago at the last meeting of the projected Schifffahrtsmuseum at Lake Ammersee, I think it was in september 2009.
Your boiler is really perfect, doubtless. But when a boiler like mine is well made and the pressure test is allright I think the risk is very low. I also make boilers from brass since 1989 and the older ones since 20 - 27 years are in use and still allright. I never got any leaking - after presure test was ok.

Regards

Thomas

[Hankwilliams]

Upper deck finished!

After the boiler trouble I continued with the upper deck. It`s now finished and varnished. The middle part above the boiler and engine area is removible.
Some pictures will show the progress, I hope. Next job will be the boiler and the radio control equipment.

Regards

Thomas

[Hankwilliams]

Good evening, dear friends and neighbors,

this time, all things went right - boiler is absolutely tight, engine is running, feed pump also in good function!
Until now, no altering seems necessary, except the fixing of the paddlewheels to the shaft, which must be stronger. You see, I ´ve installed a triad steam pipe, which will be later in the fore funnel.
I am glad, that now the propulsion seems ok. Hope, you will enjoy the pictures! Deplacement of the boat is now exactly 12 kg, the superstructure on the upper deck and the radio control may be not more than 1,5 - 2 kg weight.

Thomas

[Mechanicboy]

About boiler made of brass: In no case the boiler explodes or engine becomes broken as long as
you use in the normal range of operation.

Brass boiler is safe so long you are not violate rules on the safety of using the boiler made of brass. Take pressure test to be sure the boiler is safe to use.

See the picture of the boiler after pressure testing by Saito Seisakusho co., Ltd.

[derekwarner_decoy]

Hullo Thomas.....all looking good .......... again I do like the steam inlet and discharge manifolds you have constructed

Will you lag them?.....you may save some 3 degrees C with the steam inlet manifold if lagged back to the cylinder ports

Where did this external leakage come from? ....which appears to be on the atmospheric steam exhaust .........

Derek

[Hankwilliams]

Hi Mechanicboy, hi Derek,

its really astonishing, how much pressure a brass boiler can stand. Especially when we realize, that the maximal pressure of our boilers are only 10 % of this testing pressure. I also never heard about any exploding model boilers. May be, that the doubtfulness of exploding boilers is more a psychological problem.
From a co-worker of a factory of pressure containers I heard, that also with extreme pressure tests - which destroyed the containers by cracks - there wasn`t any explosion with the apprehendet after evaporation (don`t know, whether this is the correct expression). The steam and water has  only escaped out in a fast and strong manner.

But this is an interesting point: Perhaps any member of our blog has more experiences about boiler damage and steam escape?

Derek: The leakage comes from the gasket of the steam outlet. It`s ony fixed with two 2 mm screws, I will improve this.