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Post by andrewtoplis on Dec 1, 2021 23:18:57 GMT
Thanks David, yes I have had some citric acid sitting inside the boiler for a little while, came out a funny blue colour...
Hopefully once the new pipes have been sorted she will be good to go (well, once the lubey headache is addressed...).
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Post by andrewtoplis on May 6, 2022 11:35:35 GMT
Quick update - progress has been static for a while due to life just getting in the way - although this is due in part to a new lathe which needed cleaning up, so my fault really! New steam pipe assembly made up at the club last week, here it is on a test fitting. Regulator piece is the original, just slightly opened up, allowing for larger diameter pipes to the cylinders. Gaskets next. I decided to stick with the LBSC cylinder lubrication arrangement in the end as time is limited and I would like to have this going in the summer (this summer, 2022!). Once this is finished I can move on to the chimney where the blast pipe fitting blocks the majority of the opening; this will be a bit of a head scratcher...
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dalboy
E-xcellent poster
Posts: 235
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Post by dalboy on May 6, 2022 19:04:30 GMT
Watching with interest as I am fortunate that the Invicta loco which this is based on is just down the road from me
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nickc
Active Member
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Post by nickc on May 18, 2022 13:58:35 GMT
I have only recently read this thread for the first time and the discussion near its beginning on legacy boilers not being built to modern standards make me ask the following philosophical question:
An existing design has grandfather rights and calculations do not need to be provided to comply with the testing code. At what point do changes for for the better nullify this provision? Does adding bushes in place of a tapped boiler plate make this a new design? Soft solder caulking would still be permitted if the original design said as such eg: Midge and I have recently seen a popular boiler design where the drawing says all joints to be brazed or sifbronzed except tubes. Would silver soldering these invalidate the grandfather rights?
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Post by chris vine on May 18, 2022 18:55:03 GMT
Hi Nick,
That is an interesting question which common sense should be able to answer. (I don't mean common sense from you, but from inspectors/rule makers).
However, once you start asking these questions, it could lead in all sorts of directions. Beware!!
Chris.
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Post by philh1aa on May 18, 2022 19:42:21 GMT
Nick,
This is what I have gleaned over a few years with boilers. An additional silver soldered bush obviously strengthens the boiler, so no calculations required. High temperature soft soldered stays are still ok but I am a bit hazy on the use of loctite style stays. Silver soldering the side stays obviously improves the boiler strength - so no additional calculations are required.
Whilst we are at it, for small copper boilers at say 3 1/2" to 5" gauge - I have asked several times what calculations are required and nothing is ever presented. Just a bit of waffle about wall thicknesses and side stay diameter/ spacings, all of which can be easily tabulated based on historical practice. Any calculations are never independently checked (how can they be) and there is nobody to approve them anyway. I think people waffle on about 'calculations' to make them feel comfortable?? Who knows?
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Post by andrewtoplis on May 19, 2022 18:46:34 GMT
Back on the Lamb,
I have reassembled the steam pipework including using nuts and studs to secure the exhaust steam pipes (the pipes are at an angle but the joint is horizontal not as per the design making access to the front holes almost impossible, they were not secured when I got it). I've also made a new lid for the lubricator.
This just leave the chimney, where the blast pipe blocks most of it (photo to follow!). We think we will go with something like Rainhill, where the chimney is slotted on from above, allowing us to reuse the current smokebox and lower part of the chimney, make a new blastpipe and attach it to the exhaust steam pipe permanently, then have a new chimney piece that will slide on from above. I hope this description makes sense and I'll post up a diagram when I have one.
Once that's done we can think about putting a fire in it ...
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Post by andrewtoplis on May 20, 2022 9:01:00 GMT
Adding the chimney photo - you can see how the blastpipe fills most of the space, plus it is loose so will fall to the left or right! On the LBSC drawings it should be central.
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Post by chris vine on May 20, 2022 10:00:09 GMT
HI Andrew,
You may need to keep the chimney fairly clean. On a 7.25" gauge version of this loco, it wouldn't steam one day. Turned out the free passage in the chimney is about halved by a very small build up of soot on the inside of the chimney and outside of the blast nozzle block...
Chris.
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Post by andrewtoplis on May 20, 2022 19:34:51 GMT
HI Andrew, You may need to keep the chimney fairly clean. On a 7.25" gauge version of this loco, it wouldn't steam one day. Turned out the free passage in the chimney is about halved by a very small build up of soot on the inside of the chimney and outside of the blast nozzle block... Chris. Thanks Chris, I think the new design will be easier to clean as it will come apart!
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Post by andrewtoplis on Aug 19, 2022 11:45:51 GMT
I've been quiet here recently, a new job and general life have slowed things down. But here she is, ready for a steam test! As you may remember the old blastpipe and chimney arrangement was not happy, so to balance this with trying to save the original smokebox I have gone with a three part solution. The smokebox and lower chimney are retained, and the lower chimney part rises up to half way around the blast pipe hole. Then a new blastpipe itself is slotted in (and all being well can be semi-permanently mounted with some thread locker), then the new upper chimney slots over the original and slides down to the smokebox. Yes the joins are visible, but it seems an achievable solution to what was otherwise a difficult problem. I'm fighting the itch to paint it immediately... I'll let you know how she performs next week.
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Post by andrewtoplis on Aug 25, 2022 13:28:16 GMT
A mixed report, she lit up happily and climber quickly to 60psi on the electric blower.
Once we swapped to the loco blower the pressure began a gradual drop down to about 40psi, then recovered with the electric again.
Conclusion is that the locos own blower isn't doing the business, the pipe finishes quite low in the smoke box, so I'll try annealing it and reshaping to discharge closer to the chimney aperture rather than lower down.
Few leaks to fix as well, needs a new gasket on the top of the 'dome' and feed to the lubricator.
So mixed news but nothing worrying - I'll take that!
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Post by ettingtonliam on Aug 25, 2022 15:10:53 GMT
My loco has the blower pipe bent into a ring which surrounds the blast pipe, and has 3 No55 holes drilled in it facing upwards. Otherwise, if that takes up too much room, just bend the end of the blower pipe upwards, set just below the top of the blast pipe. Failing that, just drill the end of the pipe a bit bigger!
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Post by andrewtoplis on Aug 26, 2022 18:13:20 GMT
Thanks Liam,
The lamb does not, sadly, have a conventional blastpipe, instead it comes into the chimney above the smokebox and discharges upward. The blower pipe is lower down, in the smokebox itself, and at present is jetting steam against the underside of the 'blastpipe' elbow, which may be spoiling the gas flows. My plan is to move the end of the pipe upwards and forwards, hopefully this will give a better draw. Drilling the hole out a little is plan b!
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Post by ettingtonliam on Aug 26, 2022 18:31:46 GMT
Yes, that should definitly be an improvement! Locomotion has a similar arrangement, with the exhaust pipes feeding into the sides of the very tall chimney, and discharging into a manifold with the blast nozzle on the top. It does take up a lot of space in the chimney. A lot of traction engines worked like this, nd worked well.
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Post by andrewtoplis on Dec 5, 2022 17:26:29 GMT
Gosh, it has been ages since the last update! Work, life and everything getting in the way... I've made some progress on the Lamb since the last update...the smokebox has been milled out to open the aperture out much larger, various gaskets have been replaced, the hand pump checked and a few other bits. The last job remaining for this week is to anneal and re-shape the blower pipe, then loctite the new blastpipe into place. After that, I have decided to place her on the shelf for the time being. It'll be a complete and 'together' loco, but I have no track for testing on at present, so she can rest for a little while on a short display track panel I've been given. The bug has bitten deep though, and the next project is waiting in line, actually the next two projects (eeek!) The Simplex is actually 95% complete, the boiler being professionally built about 7 years ago but never used. Not in the picture are a completed kit of tanks, bunker and cab from MEL, an ashpan, grate and even a lubricator...really all this one needs is the reversing lever and the reversing rod down to the valve gear then lots of pipework, assembly and painting. This was my 40th birthday present a few months ago. The Maid was an ebay impulse buy. An older engine, it was run at the St Albans club until about 1990 then put away in an airing cupboard for about 30 years until the owner's widow put up for sale in the recent Dreweatts auction. It didn't sell there (not really surprising when you think of the museum quality engines they usually have, whilst this is a common MoK) so went on ebay instead where I was amazed to purchase it at what I consider a fair price. The boiler looks ok on a visual inspection but running on air reveals problems with the crank axle, which requires a lot of stripping down to get access. The club guys have had a look over it and think there is a broadly similar amount of time required to get either engine sorted, so Simplex first because I don't want two engines in pieces! At my current work rate these will keep me busy for the next few years but that's fine, I am in no hurry! PS if anyone from St Albans MES knows any history of the Maid I would love to hear it.
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