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[kno3]

Hello,

Haven't posted here much of my own work lately, so now it's time for some news. I've been busy building a new steam plant and here are some photos. This isn't going to be a step-by-step build thread hough, as I didn't take so many pictures.

The idea was to make a very compact unit to fit my steam tugboat or maybe another boat in the 40-60 cm range, so I figured using a very small and relatively light boiler with an engine driven water feed pump would help reduce weight without compromising running time.
I have used parts from Cheddar, Modellbau Niggel, Dampfmodellbau Keifler, Regner and Forrest Classics/Bix and had to fiddle quite a lot with them to make everything fit together, especially since some are metric and others imperial.
 
So I chose the boiler from this Cheddar Pippit steam plant, as it is really small and can fit a large burner. The rest (base plate, engine, lubricator are waiting for some use).


Then I made a new base for the steam plant, out of brass sheet. I had to get a sheet metal folding device to get a decent result (seen in photos below).
The boiler has one central flue with 3 water tubes. Thinking about how to get the most out of this small heated surface, I decided to use a large diameter ceramic burner that is just a few mm smaller than the boilers diameter, so it fits in the fire box. The burner was made to measure by Ludger Keifler, a German steam fittings supplier, and is about 55 mm in diameter.


This is the engine and burner layout on the base.


It's a Cheddar Pelican V-twin oscillating engine. I have fitted an oscillating pump also made by Cheddar, but the position is different from what they used to to. The lubricator, bypass valve and many other fittings are from Modellbau Niggel.


Also got a small gas tank, which I painted green to fit the boiler.


Since the exhaust steam condenser of I made for the Wilesco engine in my tug proved to be quite a space-saving and useful design, I decided to make a similar one for this steam plant. Only this time a bit more elaborate, with threaded bushings for the pipe connections. For this one I took photos of several building stages.

Starting with a brass sheet and marking the cutting and folding lines.


Folding the metal.


Making one side rounded and soldering it together.


The condenser finished with threaded bushings soldered.


And painted, green again 


And now let's skip to how this all fits together. Here are some views of the (almost) finished steam plant. It has a custom part like a steam dome, because the boiler didn't have as many connection bushings as I needed. It's been fitted with a boiler pressure regulator too. The white tubes are the connections to the water tank (one feeding and the other for bypass).












Still have to do some bits, like adding the steam whistle, making a connection for the second support of the gas tank and lagging the steam pipes.

Here is the link to a video with a test run, with the bypass valve a little open to keep the boiler level constant. After the first runs I am pleased with the performance, the boiler seems to be able to keep the engine well supplied with steam, thanks to the large burner, and the pump works well.
http://www.youtube.com/user/wat3randfir3#p/a/u/0/2p82BmiHWnE

[SteamboatPhil]

Very nice work as always, I do like the fittings they look very well made. 

[gondolier88]

Beautiful mate- lovely to see a proper compact steamplant just like fullsize.

That condenser is a great idea -and very well made.

Have to say i'm not too keen on the german fittings- not as elegant as some of the ones from over here- but they certainly look well made.

One question- horizontal safety valve- not sure thats a good idea?

Just need to see it in a nice launch now....

Greg

[kno3]

I have to agree that many German fittings are less elegant and bulkier than British ones. However, Niggel makes very high quality parts with a beautiful finish. He also made several after my drawings / suggestions, without which I couldn't have fitted everything into so little space.

Why would the horizontal safety valve be a bad idea? It seems to work just fine.

[gondolier88]

Over time I worry that the accuracy of the valve could become comprimised- gravity will take it's toll and may wear the botom of the seat more than the top- of course this would take a long time so you would be talking years probably.

All I know is that no manufacturer, model or fullsize, makes horizontal safety valves- many with horizontal outlet but not valves.

Greg

[kno3]

Well, it is a Regner part and has a Teflon seal tip, so I doubt there will be much wear. However I might change it with a nicer one, if I can get any.

[Bernhard]

Just great ..looks so good....and a tip top ide to............

Regards Bernhard

[peter.dwight]

Greetings.
Thinking about horizontal safety valves.
The most important thing is maintaining proper function of the valve. A horizontal valve could collect debris in the horizontal parts which could build up and jam the valve.  In a vertical installation it is not possible for debris to build up. There may be other reasons as well, maybe one of our steam trained mariners could help us further.
Peter.

[MONAHAN STEAM MODELS]

I would like to start out by saying what a great job you have done putting this steam plant together! It looks like you had a lot of fun doing so too! Great work! 

As far as the horizontal safety valve goes, I would have to agree with what has been said here already in that it generally isn't a good idea. Speaking from experience with both miniature steam models as well as full size steam equipment, one of the cardinal rules has been never to mount the safety valves in a horizontal position especially if they are designed to be install in the vertical position. I have spent a lot of time working on and operating full size steam equiptment ranging anywhere from traction engines to trains to steam donkeys as well as way to many marine boilers and I have not yet run across a horizontal steam valve. That's not to say they don't exist but they are at least not very common.

Outside of the shared safety valve concern, I would like to say again that you have done a very fine job with this steam plant! Thank you for sharing. 

[kno3]

Thanks guys, both for the compliments and for the safety valve advice. The reason for mounting it horizontally is that I have limited space in my tugboat and I don't want it sticking out. During testing it seemed to work without problems in this position, but I'll check it before every run to make sure it doesn't stick. Luckily that's easy, as I only have to turn that screw out. Inside is just a spring with a Teflon tip.

[boatmadman]

If you intend to run a vent pipe from the safety valve, make sure there is a drain at a point below the valve seat, Otherwise there will be a risk of water collecting above the seat and effectively increasing the pressure at which the valve will lift.

Ian

[Bunkerbarge]

The biggest concern with mounting a safety valve horizontally is the fact that condensate will collect in the valve body and could over time and continued evapooration cause the build up of a scale that could impede the operation of the valve.  It may work fine for now but the problem would be if it is not operated regularly it may just stick.  Mounting the valve vertically would prevent this happening and is the very reason why real marine boiler safety valves are never mounted horizontally.

As a point of interest on real plant, as Ian suggests, you will always find a drain in the bottom of the vent pipe after the valve to allow any moisture collected in the pipe to drain away and not sit on top of the valve for the very same reason.  It can sometimes be a bit impractical to consider doing this in a model which is why testing the valve occassionally is a good idea or, as I've done in my plant arrange for a vent line that is not actually attached to the valve but is more like a hood to direct the steam out of the model but still keeping the top of the valve ventilated.

[derekwarner]

kno3...great work.....I think that Bernhard & you were steam apprentices at the same school

I understand that the various valve bodies as manufactured by Winfried may be slightly larger than others , but in any future build will be my preferred choice along with his brilliant lubricator with in built blow down facility  

Will this latest boiler/engine be installed in a vessel or for show only?................regards Derek  


& that is a Proxxon table saw I see hiding somewhere in the back groumd  

[kno3]

Bunkerbarge, interesting solution for the steam vent.

Derek, thanks!
I am very pleased with Winfried Niggel's steam fittings. The manufacturing quality and the function are the best I've come across so far.
The steam plant might go into the tugboat I've already built. You have seen it here. At least I made it so it fits inside (barely  ) but now I need to make a new smoke stack for the tug, because the one from this steam plant one is much shorter.
And yes, the table saw is the new Proxxon model.

[kno3]

Added a thrust bearing to prevent the propeller shaft pushing the engine shaft in and putting sideways pressure on the piston rods.


And this is my first attempt at a steam whistle. I made it by using just 6 mm, 5 mm and 4 mm brass pipes that fit one inside the other.

[gondolier88]

Hi Kno3,

Good idea with the thrust bearing.

Just one thing- looking at the solder youv'e used- while very neat, it looks like soft solder, or is it just my eyes, I do need glasses...!?

Greg

[kno3]

It is indeed soft solder, your eyes are quite good.

[HS93 (RIP)]

It is indeed soft solder, your eyes are quite good.

Why as soft solder is not suitable for that type of boiler and now it cannot be changed.?

Peter

[derekwarner]

During my original steam trials with a digital pyrometer pointed @ my ACS VB2 boiler & the JMC 3H engine ....I found the worst case.....

Boiler top = 150 degrees C
Boiler discharge valve = 150 degrees C
Engine = 75 degees C

My boiler builder [Sandy Campbell from ACS Engineering in Scotland] advised that standard 60/40 soft solder was not strong enough for steam temperatures @ the boiler temperatures & I purchased "COMSOL" high temperature soft solder for the associated boiler fittings

I have since purchased 'CupAlloy' 0.6 diameter fine silver solder wire & flux which I will use in the future

So kno3.........is the conventional soft solder OK for the intended engine use?  .............Derek
 

[HS93 (RIP)]

During my original steam trials with a digital pyrometer pointed @ my ACS VB2 boiler & the JMC 3H engine ....I found the worst case.....

Boiler top = 150 degrees C
Boiler discharge valve = 150 degrees C
Engine = 75 degees C

My boiler builder [Sandy Campbell from ACS Engineering in Scotland] advised that standard 60/40 soft solder was not strong enough for steam temperatures @ the boiler temperatures & I purchased "COMSOL" high temperature soft solder for the associated boiler fittings

I have since purchased 'CupAlloy' 0.6 diameter fine silver solder wire & flux which I will use in the future

So kno3.........is the conventional soft solder OK for the intended engine use?  .............Derek
 

yes but Derek that was with a standard burner not one that is probably twice the size Cheddar recommended and fitted to the boiler, in fact this boiler was the only one they built to run on tablets with a pipit and as a stationary engine with a dynamo .  the burner is to big for my Proteus.

peter

[kno3]

Just the steam whistle is soft soldered, not the boiler. And it is perfectly safe and OK since it never has to withstand much pressure. The valve is separate, mounted on the boiler, the whistle will be somewhere up on the smoke stack and it doesn't get very hot. Perhaps I should add that the soft solder I use is not the regular type. It has silver in the alloy too (less than silver solder though) and thus has a higher melting point than the normal soft solders used for electronics etc.
All the parts that could potentially get overheated, such as the boiler, or, even more likely, the super-heater, are hard (silver) soldered.
The engine is factory assembled by Cheddar, and the solder is whatever they used back then.

I don't understand the whole campaign against soft soldering. If you only use it for parts that don't get hot enough for it to melt and for moderate pressure ranges, it is safe.
That being said, the steam hobby has potential hazards and everyone involved should be familiar with the safe use and operation of the materials involved.

[HS93 (RIP)]

.

I don't understand the whole campaign against soft soldering. If you only use it for parts that don't get hot enough for it to melt and for moderate pressure ranges, it is safe.
That being said, the steam hobby has potential hazards and everyone involved should be familiar with the safe use and operation of the materials involved.

no campain it's just not suitable for this type of steam plant on any joints . some of us have seen pipes pop out and the amount of steam that comes out is not nice and if you are need its like a steam pressure wash cleans skin straight off. that probably why but I know you have been told on other sites and did not believe people there.or about brass boilers.

peter

[derekwarner]

kno3 & Peter.... I was not suggesting that soft soldering was unaccaptable in certain parts of the steam engine/boiler package build.....this has been discussed at length on the PaddleDuck site forum...& I am sure that most of the enlightened members  here undstand this            Derek

[kno3]

Sure Derek, I understood perfectly what you meant and you are right. That steam plant of yours looks very nice, but you don't seem to have worked much on it lately?

Peter: I am not looking for an argument and you are entitled to your opinion. But if you'd have read carefully what I wrote, you'd know by now that the solder I'm using isn't the lowest temperature variety.
And please consider: the whistle is an open pipe, nothing can pop off in it, the valve, which is silver soldered, is separate and at a distance from it.
The only pipe that could theoretically pop off is the steam pipe feeding the engine, and that one is silver soldered and made of copper.

[gondolier88]

Hi Kno3,

I'm interested in what solder you used- it's (sorry, you) made a very neat job on low surface area- whats the name it's sold under?

Greg