How not to build a boiler

[gingerneer]

After seeing other boiler construction threads here i though i would so my on. Its for a Ayesha 2.5 Atlantic boiler 3" dia x 12" long so quite small. The boiler has been finished and pass is Hydro test, there were some problems along the way. I hope that this is of use and to get other's to have a go.  I have learnt that Boiler making is as much careful planning and preparation as is the heating. This is not a complete set showing all steps of the build. The barrel is cut down the length of the fire box and then open out, the throat plate attached. All silver soldering was done with CuP alloys (no relation just a happy customer) 455 55% silver rod 1.5 dia 

IMAG0693 by tapdieuk, on Flickr

The  inner fire box and tube solder in, ready for the boiler inspector to see.


IMAG0690 by tapdieuk, on Flickr

IMAG0692 by tapdieuk, on Flickr


More later now that i have the hang of posting photos.


IMAG0001 by tapdieuk, on Flickr


Inner and outer joined together

IMAG0487 by tapdieuk, on Flickr

Test fitting the back head. The bushes in the back head were solder in with a higher melting point silver solder i think 38%. I had started to have problems with previous joints melting with the 55% silver solder. Yet to be added are the blind bushes for the fire hole door as used by Julian in his Boxhill boiler





IMAG0501 by tapdieuk, on Flickr


The back head and foundation ring are in, the sticking out bits are copper shards filling in the corners on the foundation ring.



Ayesha boiler by tapdieuk, on Flickr


Soldering the firebox stays. I was luck to have access to oxy accetlane, this made the job a lot easier. Lots of flux all over the boiler to prevent a dry joint.  


Ayesha boiler by tapdieuk, on Flickr

The test rig lash up.

Apart from a stay that i missed, the main problem was the longditudinal stays cracked there solder joint on the back head and cracking at the throat plate. This was probably due to uneven cooling and my haste to get the boiler in to the pickle tank. It took 2 reheats to solve the problems.

[jma1009]

you have done extremely well on what isnt the best of designs given it's age! throatplate problems are similar to LBSC's 3.5"g Britannia boiler, and hence well known - that you found out why and corrected same is to your credit on a superb job!
i am very fond of old AYESHA! i might have a go at a 2.5"g version having done a 3.5"g version of the LBSCR H2 Atlantic. i would love to make a 5"g version one of these days with piston valves as per fullsize!
cheers,
julian

[jma1009]

the Bluebell Railway under the leadership of Fred Bailey (who has been of great help to me with my 5"g Stepney terrier) is building a fullsize version of AYESHA! how LBSC would be 'tickled pink'! the last of the line succumbed to the gas torch at Eastleigh Works in 1958/9, cutting up having been delayed in the hope that a preservation attempt would be made.

the fullsize project is well advanced - see the link below

www.bluebell-railway.co.uk/bluebell/locos/atlantic/latest.html

IMHO the H2 Atlantics in SR livery and nameplates were one of the most attractive locos ever built. they were also far superior (performance wise) to the GNR Atlantics from which they were derived.

cheers,
julian

[gingerneer]

Thank you Julian. While i had started the boiler 2 summers ago, i was put off finishing it until this summer, your Boxhill thread was good inspration. It also helped that i finish a GLR vertical boiler which gave me more confidence. Lots has been learnt for the 'next' boiler. I am not too happy with the large fittings i am using, doing it all again i would try smaller fittings like on Boxhill. Its been suggested to braise the throat plate joint, the fillet giving the joint more strength and stability. LBSC got it spot on with Ayesha, running her dimensions through Jim Ewins engine calculations her grate area, tube length and cylinder volume are very well matched. They are good looking engines well proportion. A 5" gauge one would not be too big, although it would still be a bit of a lean over the tender. Yes i would like to see her 'full size' size sister. Livery wise i don't think i could do the lining well enough to paint her in Southern green or LBSC umber, so i am think of war time black. A bit of a cop out i know

IMAG0502 by tapdieuk, on Flickr

Lots more bit to bolt on but she is starting to look like a loco.

Will

[Deleted]

Hi Will,

You've made a super job of the boiler. It looks very neat and tidy

I've always thought that it could do with a few more tubes in it as the gas area is quite small compared to the grate area. Having said that though, I've driven Paul Hinchliffe's on several occasions and it is a joy to drive. At our 2½" day in July it was in steam for about 5 hours non stop with everyone having a go at driving. It just keeps going!

Here's the original at our recent Rugby rally:



LBSC reboilered it at some point which is probably why the boiler cladding is a different green!

John

[philh1]

I have noticed what looks like a narrow strip of copper reinforcement sheet wrapped round the underside of the barrel next to the throatplate. Is this an accepted method for closing the gap?

Phil H

[Deleted]

The extra strip is to increase the area of the joint and is a feature of the Ayesha 2 boiler and others. Bill hughes did a similar thing for his Allchin traction engine boiler but used a length of 1/8" square copper. The pressure in the boiler presses the butt joint together so it is in compression rather than tension so in theory a simple butt joint should be adequate and many older boilers are still running with this feature. The reinforcing strip just adds a bit of security, like a properly flanged joint. I believe the Australian code still allows butt joints at this point so long as the joint is brazed rather than silver soldered as brazing allows a good fillet to be made.

John

[gingerneer]

John, thanks. Its been a steep learning curve. Your build log of Helan has been a great resource. Most people think i am mad for building 2 1/2" gauge loco, i find it a nice size.

Phil H doing it again I would probable braise the throat plate, as i mentioned i did have some problems with cracking but a bit ensuring the boiler cooled down slowly are the soldering help solve that problem. I built it the the Ayesha 2 plans but with out the back head regulator and through fire box steam dyer.

Will

[ejparrott]

I don't think you're mad! My family has a 2 1/2" Anniebody, and it was us that campaigned to have the 2 1/2" rail added to the Rugby track when it was built at our current site. Used to absolutely love running her, she was an dream. Ok she's only good for pulling a driver, but she ran really well. Hopefully my Uncle will finish re painting her one day soon, or admit that he can't do it any more, and then we'll have her back to play.

[dscott]

The model weekend at the Bluebell was superb, 70 miles. Three locos in steam two double heading and my two girls enjoying every moment. My wife enjoying the scenery and journeys, my daughter everything including the engine sheds where she got Terrier oil all over her hands!!!
I just took too many photos as usual and will eventually get back to the Terrier. My daughters OO one is superb which she ran last night at the club once we had dragged her off the 5" gauge line.
David ok (55) and Katie (6 3/4) three and a half miles from a 2 1/2" track.

[Shawki Shlemon]

I can't add any more good remarks than already said above which I agree with them , well done and happy steaming .

[gingerneer]

Thank you for the comments. I do think the smaller gauges have a place in the hobby, and are seeing a resurgence. A good half hour on the lamb is more than enough to get my fix, She makes driving Juliet a doodle. Now that the 'Lamb' is mostly finished (do you ever finish a steam loco?) i can get back to Ayesha. Julian's thread on steam valves has got me thinking about trying to make the back head look as neat but practical as possible.

will