How many Boiler makers?

[Tony MartyrParticipant @tonymartyr14488]

[Tony MartyrParticipant @tonymartyr14488]

From my personal contacts with active model engineers I have come to the opinion that less than half those who happily build a running chassis are, nowadays, building their own boiler.

Since I am struggling in the middle of building my first boiler I think I know why. The skill set is not acquired during modern workshop experience. A different workshop/bench-space area is needed for dirty and hot work and the price of failure of one of the silver-soldering processes can be quite high and only found at (what you thought was) the end. Finally it is possible to buy a completed and certified unit from reputable specialists, unfortunately at a price beyond my ‘hobby fund’.

So what proportion of active locomotive modelers in 3.5″ and 5″ are now making their own boilers and has there been a recent decline?

Tony

 

[CirclipParticipant @circlip]

Sadly Tony, although there must be a higher proportion of “Machine operaters” in our hobby than at any other time, the overall capabilities I would think are less than the past. Invariably the “Older” end of the spectrum have the capability and knowledge but are hindered by the dire warnings given out by the Elfin brigade for test certs for everything, so the risk of loosing even a “Small” amount of money if you DIY put many off and entrust the largest single cost to an “Expert”.

 

  Even the so called get it wrong sometimes, and the experience of a friend who had one made to the AMBSC code (Australian and often sited as THE way to build them) and supplied by one if not the largest supplier of bits out there, was not only made incorrectly but supplied with false pressure testing papers and would have injured someone if allowed to be steamed.

 

 A British Lady boiler maker supplied one which is now sitting in a completed Loco waiting for it’s ecstatic owner to finish his own “Garden” track.

 

  The other side of the coin is the “Youths” who have instant access to T’internet and all the formulae and mysticism of steam calculations so that only transposition of numbers is required but due to being off the day when basic maths was being taught, have a problem with this.

 

  Time is another problem, yer can’t throw a boiler tergether in a couple of hours.

 

   Regards  Ian.

[mgjParticipant @mgj]

And Tony for steel boilers you need some serious bending kit and coded welders.

 

Copper boilers are less trouble, but you do need proper folding and rolling kit, and some quite serious heat because you have to get into 2 step brazing so you need to be at the 680-720C mark, and comfortably so if you are to produce good joints.. – as well as a dirty great big pickle bath. 

 

For insurance reasons I went for a steel boiler on the TE and paid for it, CE mark and all. Sorry.

[ChrisParticipant @chris16039]

Hi Tony,

You will be able to add me to the ‘had a go’ at boiler making list when the Northumbrian gets to that stage. Like yourself the cost of buying would make the project a non starter. If I fail in the boiler making, I’m afraid the mantle piece will be adorned with a running chasis. When I looked into this hobby about 25 years ago everyone seemed to do everything. On my return I have observed a huge increase in the number of ‘kit builders’ who seem to be mainly interested in playing with their toys. ( No disrespect intended, it’s great to see those as well).

I find myself falling into the catagory epitemised by a local club member who said that once a loco was on the track and running he lost interest and wanted to start another.

Perhaps someone who has been modeling for those 25 years can tell us if the likes of GNS existed back then and were as inundated with orders as they are today.

[Tony MartyrParticipant @tonymartyr14488]

Hi Chris et al

I will follow your progress with interest and will post photos of my progress in my album.

I have just managed to get hold of some sulphuric acid for an old fashioned pickling bath and am currently turning all the back-head bushes which I will solder in place with a higher temperature solder than easyflow.

I have found that cutting the large (1 1/8″) holes for the dome and the firebox to be quite difficult even on my milling machine with a boring head

Next week should solder in the throat-plate and firebox extension plate – watch this space!

Tony

[mgjParticipant @mgj]

Tony – if you are cutting copper you might be wise to grind negative rake tools if you haven’t done so already.

[KWILParticipant @kwil]

A couple of comments, two stage soldering is not required if you are careful and assemble in the right order, as I beleive the alloying at the joint actually raises the remelting point slightly. Always coat the “older” adjacent joints in flux as well, just in case. Use HT6 flux as it will withstand longer heating times before it goes brown/black. As MG-J says above, have plenty of heat available to  keep the mass warm and not by just wrapping it in brickwork.

 

Draincleaner from your friendly hardware store is largely sulphuric acid just right for a pickle.

[mgjParticipant @mgj]

KWIL- I don’t know enough about eutectic alloys in copper to know whether there is a raising of the liquidus (there is no single melting point for any eutectic). However, as a generalisation, the more heavily alloyed a eutectic becomes, the lower the liquidus, and the greater the range between solidus and liquidus, which means that the stuff can go pasty and partially melt and re-alloy and all sorts of unpleasant things. So, as I say, I don’t know enough about it to go offering a firm opinion, but my gut reaction would be – don’t rely on it.

 

I think one would be much safer to plan out the brazing, and pop these fittings and rings in with a high temp solder, and come down in a sequence. Then you KNOW nothing is going to fall apart . If you have the right kit, achieving the temperatures is not a problem, and one is half way there anyway because one has to use an HT flux, and there is not a lot of difference between say AG21 and AG2 rods in terms of cost..

 

Personally I don’t mid step brazing, and I do it quite a bit. I used to avoid it before I had the right bricks for my hearth. I still have ordinary firebricks and while they will withstand plenty of heat, (of course) I had to spend half the day warming both hearth and job while these damn bricks absorbed all the heat. Now I have one of those proper non absorbing reflecting  blankets and that makes a huge difference. I’ll get some proper refractory bricks too and the granules for packing eventually.

 

 Tony I believe you will probably need a cyclone burner as well for doing inside the firebox.

Edited By meyrick griffith-jones on 06/12/2009 13:28:24

[DMBParticipant @dmb]

I remember an ME exhibition some years ago, where there was a stand occupied by, I think, a company based in Manchester, demonstrating small (1 1/2″? square ) pure white cubes for insulation whilst boiler-making. They were using a propane burner to show how very little heat was going into their blocks. Seem to recall they were quite expensive, but apparently very effective. 

Perhaps someone may know mor and suggest a supplier?

John. 

[mgjParticipant @mgj]

John – thats the stuff- there are various sorts; ceramic foam, clay wools etc.

 

CUP alloys do both bricks and blankets. A lot of heating supplies do it too. I know Stanley boilers have sheets inside used as flame deflectors, so that might be a good source of second hand kit.

 

Whats for sure is you want to stay well away from firebricks, or,  put something between them and the flame, or they will soak up heat like  sponge. They don’t disintegrate under high temperatures, but as a liner they are not terribly effective.

[Tony MartyrParticipant @tonymartyr14488]

Thanks for your comments and advice.

I have decided to use 440 solder in the two areas which will be subjected to significant secondary heating:

The bushes in the backplate

The regulator bush in the smokebox tubeplate

Both these plates can be laid on a fire blanket (obtained from CUP alloys) within the hearth so should get up to temperature without too much gas and a 2238 nozzle.

The remainder I will solder with 842 solder and use EF flux from the same company.

The latest problem I have hit is that the Safety Valve bushes and the Safety valves listed by Blackgates call for a thread of 3/8 x 26 TPI

But neither Reeves of Blackgates seem to list tsaps of this size.

From my old reference book 3/8×26 TPI is a cycle thread – is this the correct thread form?

Tony

 

[WearyParticipant @weary]

Tracy tools have that size tap… link

[mgjParticipant @mgj]

Tony – look for a set of ME (Model Engineer) taps (and dies). All the boiler fittings seem to match them. Tracy do a set, I think LSM do them, and so do Polly models from memory. they are not difficult to get.

[James VeitchParticipant @jamesveitch82153]

Greetings Tony, et al,

Does anyone have an Internet link to the AMBSC code (Australian Miniature Boiler Safety Committee part 1 – issue 7 : copper boilers?)  It seems like this code is creeping in as the international standard, it certainly is the rule here in Australia.

It seems that boiler making is something like voodoo or black art.  No body seems to speak of it in the light of day.  When I ask “experienced model engineers” about boiler making the reaction is something akin to a 12 year old girl asking her father about sex.  Lots of evasive answers and a quick drift to another subject.  I was in a club for a while and there was a resident boiler inspector.  He was just as vague but did once show me his oily and used copy of the AMBSC code.  Now that I think about it he didn’t offer to let me look inside it he just held it before me for a second or two and then it was gone.

ME an MEW are great magazines, have they ever done a series of articles leading a novice step-by-step through the process of making a boiler?

Anyways, good luck with your boiler project Tony and keep us posted on what you learn.

Jim V.

[Tony MartyrParticipant @tonymartyr14488]

Hi James

Your experience is similar to mine and is the reason I started this thread.

As to the AMBSC code I have no direct experience but I know that  a vacuum caused by a generational gap in training and experience when coupled with a litigious society that is H&S dominated will mean that some skills will become exclusively ‘professionalised’. In such a situation the most restrictive and ‘safe’ legislation and code will fill the gap because other national organisations haven’t got the courage or the skills to modify or create their own.

In my professional life I am dealing with a parallel situation concerning automotive test facilities in Universities where many H&S officers treat the running of an engine in a specially designed cell as akin to handling plutonium – the result is that many students spend most of their time running ‘virtual’ engine models on computers; this makes the authorities feel they are keeping their students safe from possible injury but also safe from essential experience.

I would love to visit an exhibition and see a boiler made by a 21 year old, which was possible when I finished my apprenticeship in 1965 but sadly less likely now

End of rant – now off to solder the throat-plate

Tony

[CirclipParticipant @circlip]

Well you got one or two salient replies on this one Tony. Re the AMBSC code James, read my post at number two, and DESPITE one or two on other forums who have said “Just a one off bad experience, move on”, it was spotted and rejected BEFORE it became a problem for an innocent bystander.

 

  Books of rules are OK providing everyone ABIDES by them and doesn’t add ” ” I ”  think it will be OK” The number of times one reads How and How Many? even on THIS forum pertaining to boilers beggars belief that the old method of reading “Books”, just like driving, seems to be becoming a dying art. You want to learn  about Boilers?? Try TC, KNH, LBSC to name only three and there are PLENTY more, it just means delving beyond the re-set button, and that’s another reason for being unable to find many 21 or under boilermakers Tony, in toy engineering pressing that one usually means many hours/months/years, not an instant restart to a few moves ago and there ain’t any “Cheats” to acheive a safe result.

 

  Whilst explaining the workings of an all flying “T” tail on an R/C toy glider to a chap that arsked, a couple of 14(?) year olds questioned “Where did you buy it?” ( The whole glider),replying that it was all scratch built and had taken about 6 weeks on and off, the retort “Oh, that’s too long” sums up the feelings of LOTS of youfs, not ALL, and that was twenty years ago, so the instant gratification sydrome isn’t new.

 

 The Blame and Claim fraternity sprung up when “Rules of engagement” were sent over on the Exocet of American Television Law and Order programmes so as far as someone doing a write up in one of the “Popular” trendy hobby mags is concerned, don’t hod your breath. Long gone are the 50’s and 60’s when the only way for MOST to play with exotic toys was to MAKE them with out fear of someone suing them for tripping over a match dropped after lighting a boiler.

 

  NOT a rave, but simple facts of life. I won’t say good LUCK with your boiler making trials Tony, if it’s a standard design and not a “I’ve just got a drawing programme so I’m a DESIGNER” rendition, if you follow the basic rules of correct fits and cleanliness with propper fluxes etc. you KNOW it’s going to work.

 

 

[Tony MartyrParticipant @tonymartyr14488]

Well the first soldering jobs have been done today and the fact that I have read all the books (that include advice about how deep to stack the Coke) it did not prepare me for some of the lessons I learnt today by practice.

First mistake: not packing insulating mat around the throat plate sufficiently, so it took too long to get up to temperature. Got there in the end by starting again with a new arrangement in the hearth.

Second mistake: Not removing an AO drawing that was pinned to the wall above and beyond the hearth – lifting the torch while applying solder and not looking where the flame was directed nearly set fire to the boiler design and the workshop!

Third mistake: not really a mistake – more a difficulty. Where the boiler tube was cut to form the firebox there is a small hole created at both sides that was not completely closed by the throat plate (I have a photo of the area in my photo album) I had to peen the gap and re-solder, it appears to be OK (not pretty but OK)

Big success – by the time I got round to soldering the back-plate bushes with high-temp solder I had got the hang of things so got it up to red heat quickly and the solder flowed beautifully.

Also just got news that I got a grade 2 pass in my Open University course and I did not spill sulphuric acid over the garage floor or dissolve my trousers – A GOOD day!

Tony

[mgjParticipant @mgj]

Well done tony.  And the OU too. I always enjoy welding/brazing.

 

The lower temp brazes are a bit easier in some ways – the flux seems more co-operative.

 

Electric cables are good things to melt inadvertently.Recommended.

 

Pickle baths – you may have come across this already, but be careful about lowering tubed thingys in there. You can get acid drops blown out by steam forming in the tubes. I’m not a great elfin player, but I think its very wise to wear a full face visor when you get to that sort of dunking.

 

Of virtual engines – you can’t beat running up a (real) big 27litre vee12 diesel with 2 stage turbocharging on a dyno for pure fun. (Unless its cryogenic windtunnels) Thats what i call virtual motoring.

[James VeitchParticipant @jamesveitch82153]

Yo Circlip,

Sorry to say I don’t know what “TC, KNH, LBSC” are.  I do read so if they are reference books please elaborate. Thanks.

JV

[CirclipParticipant @circlip]

Sorry James, TC is Tubal Cane, KNH is KN Harris and LBSC is LBSC, all authors of books concerned with boilers and engines with formulae to get things right.

 

   Regards  Ian.

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