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[barryfoote]

Ken,

Bunkerbarge covered most of your points in his recent series in Model Boats magazine last year. If you don't take the magazine then back copies are available.

I think there is another pertinent point to be made here and that is that there may be two types of beginner, the person who wants to build his own plant (as per Vintagent's post above) and the person who wants advice on how to choose, fit and operate commercially obtained equipment. It is the latter that Bunkerbarge's articles were really intended for and theye were very well set out and easy to understand. Definitely worth getting hold of as they are up to date too. The first article and one or two of the others are free to view on the Model Boats website: http://www.modelboats.co.uk/news/article.asp?a=4447

Colin

Colin,

I appreciate what you say, but this is not "Model Boats" magazine. It is a model boat forum. If a thread is titled "A beginners guide to steam", then surely that is what it should be. I am not blaming Bunkerbarge for this, but the thread seems to have been hijacked to a point where it has no meaning. As for your "advertising post", sorry my friend but I don't think it has any place in this thread either..

[vintagent]

KenP, that's what my chum would like to know as well, if anyone can do that for him.  He is in no better position than me to buy expensive readymades, but a basic talk through of steam principles would help anyone really.
I can make an engine, but know nothing about boilers really (OK, principles, maybe)
I certainly know nothing about gas installations. 
I'd be happy if a spirit burner tucked underneath did the works on a pot-boiler+ (water tubes hanging below, kinda thing).
Regards,
Vintagent

[Colin Bishop]

Footski,

Sorry but I think you have got the wrong end of the stick here. I was not plugging Model Boats as such but simply pointing out that much of the information asked for is already in the public domain and quite a bit of it is free to read. The articles that Bunkerbarge wrote do cover exactly the same points that some people are querying here and are very informative and accessible. I suppose he could have posted the material on here instead but it took a great deal of time and effort to put together and publishing it in the magazine means that it will be seen by maybe five times as many modellers than if it were to be solely confined to Mayhem and his main objective was to promote the use of steam to as many people as possible.

However I do accept that different people have different ideas on what a Forum is for. If I am starting an interest in an entirely new subject then my practice is to read up on the basics first so that when I do need help in understanding some of the detail I can post my queries in a specific and reasonably informed way which will hopefully not impose too much on the time of the knowledgeable people who are prepared to help me.  If they are prepared to give their time for free then the least I can do is to put in a bit of preliminary effort myself.

Bunkerbarge has suggested a couple of books himself for people to look at but understandably has not wished to plug his own published material. I thought it only right that attention should be drawn to that.

Colin

[Circlip]

Ok, to give easy answers to Ken.

  1. Engine, boiler and propellor.

  2. Depends on size of engine.

  3. Depends on size of Boat and depth of pocket.

  4. With water.

  5. A match or cigarette lighter.

  Regards   Ian.

[Bunkerbarge]

Whoa, 'ang about chaps!! I seem to remember being the one trying to get this thread back to a beginners thread in the first place and now I'm being accused of taking it off at a tangent!

I wouldn't mind but I only started it because a member asked me to

[barryfoote]

I give up. Sorry Bunkerbarge. it was a good idea, but..............

Not your fault at all..

[Colin Bishop]

It's still a good idea but maybe needs some parameters attached. "Tell me everything about steam in model boats" is a bit ambitious but dealing with queries from people who are taking their first practical steps into putting together an installation is possibly more appropriate.

Even 'simple' steam in model boats is quite a complex subject. I would certainly class myself as a beginner and I found Bunkerbarge's articles to be pitched at exactly the right level for somebody thinking about having a go at it. But his initial series or articles filled 12 pages in the magazine and he needed to add a postscript by popular demand to cover various outstanding odds and ends. Realistically I can't see the subject being covered in much less space so why would anyone want to repeat the exercise on here when the job has already been done?

Bunkerbarge's articles certainly gave me an excellent insight into just what is involved in setting up a successful steam installation using mainly commercial components which is the easiest way into the subject and my personal conclusion was that, while I find steam fascinating, I simply lack the degree of commitment needed to get involved in it myself. Others will take a different view but the value of the articles is that they show you just what is entailed so that you can make an informed decision for yourself.

Colin

[gondolier88]

Ok, If it's alright with everyone I would like to volunteer to add regular posts to this thread on an AtoZ of steam, it will be simple and conscise- if people are wondering about a certain point they can PM me or if it is in everyones interest to know the answer ask on the thread here.

I will start with the general principles of boiling water...(that's not a pun)

Greg

[Bunkerbarge]

Many thanks for the initiative Greg, I'm sure such posts will lead to interesting questions and follow up.

I do think it might be of value to say one or two things about the whole subject of steam in model boats.  The first is that there is no magic answer, nor is there any holy grail that can be given to anyone to answer such sweeping questions as has been suggested.  There has to be a degree of 'finding out for yourselves' and whilst there are a number of us willing and able to help the cause being met with a "Tell me all about it" type of approach leaves us floundering because we don't know where to start.  It is going to be far easier to deal with a specific question and then let that lead to further discussion and questions rather than try to spoon feed what we think may be required.

As Colin has indicated I have written a series of articles that were published in Model Boat magazine and some of them remain available on thier web site for every one to read.  These were aimed at newcomers trying to get into steam in model boats but being unsure as to the basics perhaps didn't know where to start.  So perhaps reading them might be a good place to start.  I'm also getting a sense of available plant being too expensive so we need to make sure that every one is aware there are only really two basic paths into the steam world.  You either make things yourself, in which case you need expertise and machinery to be able to do so or you need enough money to be able to buy manufactured plant.  There is no point in complaining that you can't afford to buy manufactured gear, it's expensive and we can't change that.

I hope that we can use this thread to give some advice and guidance to beginners, as I said in the first post, and help them to select the type of plant they want to use as well as support some of those decisions with a bit of background to some of the questions that may arise but I don't think it will become a "Steam For Dummies" presentation.  As Colin suggested, steam requires a much higher degree of dedication than you need for electric propulsion so there is never going to be a quick and easy fix into the subject.

Over to Greg and his boiling water

[gondolier88]

Ok guys and gals here we go;

Water is a liquid that starts to freeze from 4deg and below and boils at 100deg in perfect state, and from 98.5 to 101deg with certain minerals and characteristic chemicals added.

It is a fantastic conductor of heat and heats quickly given the right conditions-large surface area to water volume  being the best conditions, for example;

Those that have old kettles that go on the gas hob and replaced them with an electric kettle with a large element have the same surface area and heat input should boil water at the same speed despite the heat sources being completely different.

HOWEVER, I wrote should because as water heats, especially if it heats rapidly it begins to circulate, a rolling boil being the best example of this- if the water is heated from the bottom then the ‘cold’ water will fall at the furthest point from the heat source- in a kettle this would be on the outside of the kettle- and the hot water will rise rapidly up from the heat source.

Thus our example of the two supposedly identical kettles that should boil water at the same rate is slightly flawed;

If the kettle with the element has a coiled element in the centre of the kettle at a point raised above the bottom of the base of the kettle then it will circulate the water quicker- for various reasons that most are too complicated to include at the very beginning of the thread!

One way to ‘force’ circulation is to manipulate the shape of the boiling area- for example a vertical cylinder heated from the outside at it’s base will have conflicting circulation currents- however link the cylinder to another vertical cylinder  at it’s base and at the top, still just heating the original will allow all the hot water to rise in the heated tube and the cooler eater to circulate back down the other to re-enter the heat exchanger at the base- a process known as ‘natural convection’ in boiler design.

However, this simple situation can be further improved by manipulating the boiler shape and increasing the surface area-

If cone shaped cylinders are used- the base of the heated cylinder being thinner at the top, and the base of the circulating tube thinner at the bottom then these will act as venturi tubes (the process of increasing velocity of a gas or liquid by narrowing it’s path and suddenly expanding it again) speeding up circulation,

To speed up circulation even more surface area can be increased.

The reason we do all this is that steam is not just a thin vapour that rises from water when heated, but is formed as tiny bubbles in the water at the heat source that stick to the surfaces of the boiler- the champagne glass principle- by forcing circulation as much as possible these bubbles cannot adhere to the sides (acting as insulation and wasting heat)- just like shaking your champagne glass has the same effect.

Just as important as making sure the heat is used in as efficient a manner as possible by giving it as much water to heat in a given period of time as possible is keeping the heat that has been put into the boiler in the boiler, or In other words INSULATION.

I think we all know how important insulation is in our houses that try to keep in 18-21deg- increase that temperature by 5 or 6 times and the job is far harder.

PUT AS MUCH INSULATION AROUND YOUR BOILER AND ENGINE CYLINDERS AND ESPECIALLY PIPEWORK AS YOU POSSIBLY CAN!

The main variables for boiling water are thus;

- Heat input
- Water circulating properties
- Shape of boiling area
&
- Insulation levels

I hope this has been patronising to the regular 'steam' posters on here- if so it means it's as simple as I meant it to be.

Greg

[Bunkerbarge]

If Greg doesn't mind me adding to his explanation I think it is useful here to also discus the differences between heat and temperature.  Heat is basically a measurement of internal energy which everything has.  Some things have a high energy and some a lower energy.  This heat energy is capable of transferring from one object to another by any one of the three transfer paths, namely conduction, convection and radiation. 

A consequence of heat is temperature but not necessarliy such that the higher the energy the higher the temperature.  For instance if you add heat to water from a burner the temperature in the water rises as it's internal energy rises.  When it reaches the boiling point though the heat energy is then used to change the state of the water to steam and so even though you may be still putting more heat into the water it's temperature will not rise.  This heat is known as latent heat and any given substance has a specific latent heat, which is the amount of heat required to change the state of a specific quantity of the substance.  If the substance remains open to the atmosphere continuing to add heat will not raise the temperature but will only continue to change the state of more of the water, as in a normal kettle and explains why the temperature of a kettle does not rise above 100 degrees C, depending on atmospheric pressure.

If you then contain the escaping steam it generates a pressure on it's container as more water is changed to steam until it reaches it's vapour pressure at which point the system is said to be in equilibrium.  Adding more heat then does two things, it increases the temperature of the steam and it increases the pressure, which remain related.  This is why for those of you with Cheddar Electronic Gas Control systems the probe in the boiler actually measures temperature and not pressure.

So that's the basics of what is going on in the boiler and again thanks to Greg for getting the ball rolling.

[RaaArtyGunner]

HELP.   
Guys remember the KISS principle 
Keep It Simple Stupid 
Yes a lot of us do need big spoons the bigger the better.
Reading this thread, If it sounds too complicated and difficult why would I want to start in steam, know nothing about it and at this rate will never do so.   
As for references to "Model Bots magazine articles" and public domain       that all depends on how you search and your current knowledge, no knowledge so what do you look for and where hence the questions for help.
We are not all on the same level    let alone sometimes not even the same wavelength  and we all don't have the same deep pockets.  
Now  I stand guilty of having completely got of the thread.   

[Colin Bishop]

Well, as far as Model Boats Magzaine is concerned it doesn't get much easier that this:

http://www.modelboats.co.uk/news/article.asp?a=4447

http://www.modelboats.co.uk/news/article.asp?a=4853

http://www.modelboats.co.uk/news/article.asp?a=4853

The other articles are available if you have a subscription or are willing to purchase them. The publishers are in business to sell magazines rather than give out free advice I'm afraid.

If you want to understand the subject then, as I have previously said, you need to put a bit of effort in yourself. It's not rocket science!

Colin

[vintagent]

If I may sing a chorus for those of us who want it simple...get on Pete Atkins' website and listen to the Locomotive song from Beware of the Beautiful Stranger. No more concise explanation is there for how a steam loco works! (The other songs are magnificent too!)

Also, don't forget, people like Raartygunner, that you could put a Mamod or SEL or Willesco "toy" steam plant in a boat and have almost as much fun because when it's out on the water chuffing away, nobody can see all the magnificence of the model engineering OR the lack of it. It's just a steam boat at a distance.  So some of the need for Cheddar, Monahan, etc. plant could be seen as a bit of one-upmanship.  Fair enough. Some are impressed by that.  Some, like me are as unmoved by that as by TV advertising.
Of course some people have no space, equipment, skill, etc. and can afford the above so have to have it if they must have steam. Equally fair enough.
All I'm saying is a glorified pot-boiler, a spirit burner and an oscillating plant will still give you hours of pleasure on rudder only.  But do test it first to time the length of run.  You don't want all the solder running out of the joints on your Mamod!

Fun IS available with a little imagination without breaking the bank.
Of course these little units can be made without the facilities of an engineering shop, too.

Regards,
Vintagent

[Circlip]

Well, as far as Model Boats Magzaine is concerned it doesn't get much easier that this:

http://www.modelboats.co.uk/news/article.asp?a=4447

http://www.modelboats.co.uk/news/article.asp?a=4853

http://www.modelboats.co.uk/news/article.asp?a=4853

  But what does this mean Colin, how does it help???????????   Do I have to do something??

  Regards  Ian.

[vintagent]

Having said all that above, I have just looked at the Maccsteam site and am frankly amazed at how remarkably inexpensive are his products.  I couldn't begin to produce those components at those prices.  I could make them all on my wee lathe, but I would have to ask myself it it was worth the trouble. A beautiful valve assembly with handwheel for £15???  Amazing.
I add that I have no connection with this company other than a bystander led to his website by another thread on this forum.

If I could justify spending there I wouldn't hesitate!

Regards,
Vintagent

[PMK]

I know that I'm not exactly the most popular bloke amongst all you steam buffs (probably my own fault for being a twonk in the first place), but could I throw a couple questions your way?.........

Did any of you go the Shepton Mallet gig in April? Just outside of the hall where ACTion, MMB and several other traders were doing their thing, was a chap with three of four models (VERY nice models), each fitted with their own steamplants. I was having a long chat with the man who built/owned them, and he was telling me about this wee electronic gizmo he'd installed in each model, only I didn't get to learn what those gizmos were because some other chap came along and we all got sidetracked. All I know is that they (gizmos) were some sort of safety device - something to do with preventing the engine from exploding. The only other thing I learnt is that each one cost the man something like £150.00 each. I was shocked by that because, when he popped the lid, I peered inside and saw just one 8-pin chip, a small on-board trimpot and a couple other discrete components. All pretty much bog-standard components, and no way was there anything to the value of THAT much. I'd guestimate that one could build the same and still see change from a twenty.
From this, albeit scratchy discription, would you steam boys happen to know what that gizmo might be?
Would you be perhaps interested in paying far less for a homemade one?

(Total apologies for taking your thread slightly off course).

[Bunkerbarge]

My guess PMK would be some form of gas contriol device.  The problem with a basic unit which pumps gas into the burner is that when you don't use the engine the pressure rises until the safety lifts, then you are simply wasting energy.  If you can turn the burner down to control the flame and prevent the safety from lifting then that is a huge advantage.  Mechanical ways of doing this are the attenuator valve, which uses a diaphragm pushed by the boiler steam pressure against a spring, to control the gas flow, or electronically like the old Cheddar Electronic Gas Valve, which is now produced by Stuart.  This uses a temperature sensor on the boiler to switch the burner from a ful flame setting to a pilot flame setting, thereby regulating the boiler presure.

I think I know the chap you are talking about and, if it's him, he makes absolutely everything from scratch.

[Bunkerbarge]

Well from what I can see above we have the opinion that anyone who has anything more complex than a Mamod is showing off and any teachings have to be in words of one syllable preferably not involving anything more technical than junior school physics and I suspect there are some who would struggle with that.  I accept that Macsteam products are beautiful and very reasonably priced however once you have looked at fitting out the boiler and added all the other bits you need you will still be a bit surprised at the total cost.

Bottom line I'm very dissapointed but there is obviously no demand for such a thread as this and maybe I will just have to accept that steam in model boats will be a victim of our society and die out with this generation.  I'm certainly not going to waste any more time on this thread.

[PMK]

"I'm certainly not going to waste any more time on this thread."

Don't give up. Some of us do read/do appreciate these things, you know.

I think you could be right about that gizmo, because, now that you mention it, I do recall a length of wire protruding from the box, terminated with a sensor on the end (presumably the temperature sensor you talk of). If this isn't too cheesy a question, what sort of temperatures do those boilers reach? In your opinion, does £150 sound like a lot to you?...or did I mishear the man? I would imaging that £150 is perhaps a small price to pay (especially in view of what those engines are worth) and at least safe in the knowledge that you're protected from any explosions or such, but would you agree that the same thing could be made a heck of a lot cheaper?
By the by, I'm not trying to cheapen things, and certainly not trying to muscle-in on anyone's profit, but I still think that you steam boys are perhaps getting a tad ripped-off?

[Circlip]

Nil Illigitum BB

[The Antipodean]

I have found this thread not only informative but entertaining as well.
As a not even an absolute beginner in steam I am curious to know more as I would love to build a steam tug at some point in the future as my situation has changed for the better and steam now looks as though it once again could be a prospect.
Bunkerbarge, you do wonderful explanations, I would think that if a person did not understand them they should maybe ask for clarification of the part they don't understand instead of saying the whole thing is useless.
From what I have seen in the steam forum, the people who have steam are always looking at encouraging more members to join them on the humid side of boating and I would guess they would actually be amazed that they had turned people away.
I would say it comes down to how much a person is willing to do to learn about a subject they say they are interested in, some want spoonfeeding and some are more than willing to do the research themselves.
Basically, if someone asks a question and it is answered, if someone else doesn't get it they should ask for a little more explanation and as long as the person who asked the initial question is satisfied with the answer then there is no problem at all.

Longwinded I know but my opinion on a good thread.

Ian

[Bunkerbarge]

"I'm certainly not going to waste any more time on this thread."

Don't give up. Some of us do read/do appreciate these things, you know.

I think you could be right about that gizmo, because, now that you mention it, I do recall a length of wire protruding from the box, terminated with a sensor on the end (presumably the temperature sensor you talk of). If this isn't too cheesy a question, what sort of temperatures do those boilers reach? In your opinion, does £150 sound like a lot to you?...or did I mishear the man? I would imaging that £150 is perhaps a small price to pay (especially in view of what those engines are worth) and at least safe in the knowledge that you're protected from any explosions or such, but would you agree that the same thing could be made a heck of a lot cheaper?
By the by, I'm not trying to cheapen things, and certainly not trying to muscle-in on anyone's profit, but I still think that you steam boys are perhaps getting a tad ripped-off?

Thanks for the support PMK, I can assure you it is very much appreciated.

This device does sound like an Electronic Gas Controller in which case you are up against the unit from Stuart Turner.  This includes the change over valve itself as well as the sensor and a gas pipe to connect the tank to the valve.  These are currently in the region of 140.00 UKP so you would have to do better than that to be competetive.  One possibility may be to sell just the electronics package and leave it with modellers to sort out thier own valve but I suspect most will want the valve including as well.  The way it works is that the valve changes over from full flame to pilot via an operating arm, which is moved by a micro-servo.  The servo gets it's signal from the control box, which in turn is activated by the temperature probe on the boiler.  The 'pot' you saw would be the pressure (technically temperature) set point so the unit is really only measuring the difference between the set point and the sensor input.  As you say it is pretty basic but very effective.

As for temperature if we take 100 psi, which is above what most model boilers should be working at, Cheddars are around 45 psi and Hemmens are about 80 psi, then the corresponding saturated temperature is 332 deg f or 167 deg C.  Test pressures are initially 2 x working pressure and subsequently 1.5 x working pressure so you could be looking at 187 deg C so I'd be looking for a sensor that can withstand 200 deg C.

[Bunkerbarge]

I have found this thread not only informative but entertaining as well.
As a not even an absolute beginner in steam I am curious to know more as I would love to build a steam tug at some point in the future as my situation has changed for the better and steam now looks as though it once again could be a prospect.
Bunkerbarge, you do wonderful explanations, I would think that if a person did not understand them they should maybe ask for clarification of the part they don't understand instead of saying the whole thing is useless.
From what I have seen in the steam forum, the people who have steam are always looking at encouraging more members to join them on the humid side of boating and I would guess they would actually be amazed that they had turned people away.
I would say it comes down to how much a person is willing to do to learn about a subject they say they are interested in, some want spoonfeeding and some are more than willing to do the research themselves.
Basically, if someone asks a question and it is answered, if someone else doesn't get it they should ask for a little more explanation and as long as the person who asked the initial question is satisfied with the answer then there is no problem at all.

Longwinded I know but my opinion on a good thread.

Ian

Many thanks Ian and again, very much appreciated.  You see it pretty much as I do and whereas I'm more than happy to give as much of my time as necessary I get a bit negative when I see complaints about the cost of steam plant and complaints about the fact that we are not teaching members at the right level.  I have put huge amounts of time and efforts over the last few years to try to get more modellers into steam and was very pleased to see our first Steam Convention at the Kirklees Model Boat club recently but people have to take steps themselves and show a degree of initiative as well.  It is not my responsibility to teach someone something, it is thier responsibility to learn and, as you say if they don't understand then ask the right questions. 

At the end of the day I went out and bought the books and read them and I expect a degree of the same from anyone who wishes to become more involved in steam.  If your attitude is that anyone with anything more complex than a Mamod or a Wilesco is showing off then please go and buy a Mamod or Wilesco and be happy with it.  There is a member on here who has an old launch with a plant that has been out of production for a long time however he did some research and found some information on it and I was able to complete a steam test for him and get him on the water.  I was more than happy to help him but the initiative and effort came from him in the first place.  Coincidentally as well his plant was of the Mamod/Wilesco type but he didn't see me as showing off with a Cheddar plant, he was just happy that I'd certificated his plant for him.

[steamboatmodel]

I have run a Wilesco D48 for a number of years in a Mabel style hull, and have had many hours of enjoyment from it. The main problem I find with it is the original boiler, to solve this I have been experimenting with different boiler designs. For the absolute beginner I think the Midwest engines/boilers are a good place to start. There have been many designs published over the years for simple steam engines and boilers here are a few that I had posted on the RC Groups Steam section;
http://www.rcgroups.com/forums/showthread.php?t=1226384

Building Simple Model Steam Engines
Books 1 & 2
by Tubal Cain

Making Simple Model Steam Engines
Model Marine Steam
by Stan Bray

Another Article/book to add,
Safety of Copper Boilers by Kozo Hiraoka this nine page article was first in Live Steam & O.R. (Vol. 40 No. 6 Nov-Dec 2006) and is included in Building the New Shay.

Introducing Model Marine Steam
By John Cundell and Jim King.

Model Making 1919 Edition
By Raymond Francis Yates
Also
Boys' Book of Model Boats
By Raymond Francis Yates
http://www.gutenberg.org/files/29064...-h/29064-h.htm

I have been building model steam engines and boilers off and on since 1967, but still find the articles for beginners enjoyable and quite often informative.
Regards,
Gerald.