|Nick Clarke 3||22/10/2020 17:05:43|
937 forum posts
While I agree with many of the comments in the letter in the latest ME decrying the inaccuracy in many valve gear designs, those on LBSC's challenge to K.N.Harris require some comment.
LBSC's original challenge was:-
While the reply from K.N.Harris was:
So instead of LBSC 'backing out' what actually happened was that KNH refused to take up the challenge as given but instead wanted to pitch a 'Maid of Kent' against a tank engine designed by, but not built by him in order to 'prove' a quite different argument.
So while the arrogance of LBSC's challenge might be questionable, his opponent never had any intention of accepting it in its original form.
(Extracts from ME 3292 and 3296)
Edited By Nick Clarke 3 on 22/10/2020 17:09:39
5569 forum posts
What I see is a subtle dig at the accuracy of LBSC's published drawings and the efficacy thereof ........
Applies to a few other designers too.
|Neil Wyatt||22/10/2020 18:41:41|
18322 forum posts
Has to be the longest running argument in the history of British publishing...
|Nigel Graham 2||22/10/2020 19:03:11|
|802 forum posts|
I have no idea what is behind this resurrection of their old argument, but I have had experience of a 7.25" version of Juliet built as a club project and I have the drawings for Maid of Kent, the latter with both Lawrence and Harris motion-work options.
I also leant to drive miniature locomotives in the late-1960s on a Maid of Kent built and owned by the society before my time, almost certainly to LBSC's drawings unless its Joy Gear option was Harris' modification.
Whoever built our Juliet's chassis simply doubled the dimensions but largely kept to the original arrangement. The completed loco ran very well on heavy portable track duty for several years; and its eventual failure in service exposed the main weakness in LBSC's design.
It had nothing to do with ports, valve settings and the like, but mainly and simply that the valve-rod clevis was suspended from a single-sided link swinging on a pin affixed to the frame. Consequently, accumulated wear meant the motion was doing more waggling in fresh air than anything useful. Rebuilt with large valve-spindle guides bolted to the stretcher, and better connections to the expansion-links, the engine ran for a good number of years more perfectly well; the original steel boiler was later replaced by one built by Reg. Chambers, specially and his last, as he was a member of our society - and Julia is now in my ownership awaiting freer times and a boiler-test. (Anyone have a spare Round Tuit available?)
Julia was actually LBSC's own light-hearted suggestion in the original "words & music", after a number of people had suggested a doubled-up version.
And the Maid? I think Harris revised the port dimensions and eccentrics for the Stephenson's Link Motion option, but otherwise basically improved the mechanical details, as above.
The society's Maid was very well built and ran very well. Unless as I asked above, its Joy gear option was to Harris' idea and design, it would probably have been largely faithful to LBSC's drawings, though with some minor tweaks like 'Tufnol' manifold-valve hand-wheels. It was also name-plated Maid of Athens; I know not why but still sometimes wonder where "she" went and hope she is still happily running.
I know it is now fashionable to deride weaknesses more than celebrate strengths of the dearly-departed, and I know 'Curly' Lawrence had reputations; but is anyone fault-free? I am also aware there are many anecdotes of errors in published designs not being corrected by some other designers.
Let us remember though that although LBSC's design details might bear improvements in the light of accumulated model-engineering experience since, LBSC and most of his contemporaries had far more basic workshops and far less of that accumulated knowledge than available now. Yet he built many locos that worked, and many model-engineers have followed his "words & music" equally successfully.
The hobby had to start somewhere; and improving designs and processes is a central tenet of Engineering.
|Nick Clarke 3||22/10/2020 19:33:50|
937 forum posts
IMHO applies to virtually all 'paper' designers, not to have dig at them but to suggest issues with the process itself.
|Nick Clarke 3||22/10/2020 19:36:27|
937 forum posts
LBSC gave a Joy valve gear option
|Nick Clarke 3||22/10/2020 19:44:38|
937 forum posts
Personally I have issues with LBSC's designs, especially in the larger gauges - BUT as a readable journalist, writing over 40 years I appreciate all of his faults, but acknowledge his contribution to the hobby. and he is always readable.
BUT I find him far more interesting to read than most other authors, including almost all those writing about model locomotives in the seventies! (with the notable exceptions of Ken Swann and Keith Wilson!)
My opinion only - please don't shoot!!
|J Hancock||22/10/2020 20:23:10|
|479 forum posts|
If LBSC ever did make any of his engines they certainly were not to the dimensions given on the drawings !
KH could have nailed him to the floor with that specification.
|Nigel Graham 2||22/10/2020 22:02:14|
|802 forum posts|
Nick Clarke -
Thank you for clarifying that.
The Maid I knew was originally built in the late-1950s, perhaps early-60s, so probably was to LBSC's design; but I don't know what errors the builders may have encountered in the drawings. I gathered it was given an thorough overhaul in the mid-1960s, just before I joined the club.
One thing that would have helped were the presence in the society membership of the time of a few professional draughtsmen, fully apprentice-trained. Some worked for the Admiralty, one was a retired GWR man; all were excellent craftsmen.
Having criticised the designers for drawing mistakes, I must say their dimensioning doesn't always make it easy for we builders to avoid making mistakes even when the drawings' dimensions are all correct!
Besides all that, the original spat between these two luminaries just seems so petty, and I am surprised that supposed challenge based on two totally different locomotives was even made. Mr. Lawrence seemed to like a battle - boilers first, motion-work next, and some of his comments in print could be a bit abrasive even if making a valid point. The older generation... whatever was the world coming to?
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