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Post by coniston on Dec 7, 2018 23:27:20 GMT
Hi David, you could put a Tee piece in the pipe from manifold to oil steam valve, maybe hidden behind the pressure gauge? run the pipe down between blower and oil steam valve then put a new valve somewhere below and between the oil sight glass and injector steam valve? then straight down to the existing pipe union. Just a thought.
Chris D
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Post by Jim on Dec 8, 2018 11:28:18 GMT
Hi David,
Thought I'd reply here to your post on John's thread...didn't want to upset the apple cart as it's had a fair old shake up.
Beatrice is indeed a beautiful loco. I never could understand why 'they' built Princess of Wales with the steam dome on the boiler directly above the driver instead of forward to create a nice line from the top of the chimney back to the front of the cab. Apart from Beatrice the 4-4-0 were lovely locos too. I have the copper for the boiler along with a GA drawing so really, it could be a goer.
Jim.
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Midland
Elder Statesman
Posts: 1,870
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Post by Midland on Dec 8, 2018 17:42:24 GMT
Hi Jim Yes agree. Johnson lost the straight line one can draw from chimney to dome to the back of the cab. It was all to do with trying to get them from power class 1 into power class 2 using a bigger F type boiler. The wheel base for the whole engine was longer and in my view was pushing the single a bit more than they liked. If I was building one of these now I would use a 115 class loco as the model and simply change the PoW drawings to suit. The thing is that almost all Johnson's locos were more or less the same inside and that makes making one into another quite easy. Just wish I had the skills and time to do it!! Anyway we can natter here about red engine here forever!! David
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Midland
Elder Statesman
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Post by Midland on Dec 8, 2018 17:43:48 GMT
Hi Chris
Yes that makes much more sense now you have opened my eyes, thanks. D
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Midland
Elder Statesman
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Post by Midland on Dec 9, 2018 17:20:59 GMT
Jim If you see this, could find out if Australian Railcraft are still in business, they have a valve that I think will suit me fine and need to talk with them. In fact I will post a picture of it. www.railcraft.50megs.com/index.htmlHere is the pic, DC Valve by David Goyder, on Flickr In fact, here is a challenge, how does it work. I could make one myself maybe. Cheers David
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Post by Jim on Dec 9, 2018 20:40:32 GMT
I'll check for you David and get back ASAP. Jim
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Post by Jim on Dec 9, 2018 20:45:13 GMT
Hi David, They do exist and the valve you are looking for is still advertised you should be able to see it here and if not it appears under 'Fittings' It's an interesting valve.
Jim
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Midland
Elder Statesman
Posts: 1,870
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Post by Midland on Dec 11, 2018 16:52:48 GMT
Thanks Jim, will let you know how I get on. David
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Midland
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Post by Midland on Jul 11, 2021 17:35:49 GMT
Well, here we are 2 and a half years later and getting back to basics now that the wretched Princess Royal is gone. I should be careful with my words as I met the Princess Royal a few years ago and she is charming and fun and not very wretched (Tower beckons!) but the loco named after her predecessor was a bit of a wretch for me so we are back nursing the 990 into health. It still resists the four evenly spaced chuffs to the rotation of the wheels, more of a chuff, splutter, a couple of oh shits before back to the chuff. I have played with the piston valves, measured, calculated, watched dockstader and run the damn thing on air and got nowhere, stil the same old routine. So following several peoples advice the boiler is coming off so we can fix the chassis. I am even starting to understand the Deeley/ Sievert scissors gear, probably the only person in the country dumb enough to try. Not sure what it proved for the Midland except I think Deeley wanted to show us how clever he was and that is a dreadful mistake wheh you are not genius enough to know you may not be!!! Anyway will give you some pics when the boiler is off!! One day . . . . Cheers David
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Midland
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Post by Midland on Jul 15, 2021 15:34:35 GMT
Hi All I think I may have a little progress emerging. I am not sure if I have shown you this but it is a diagram of the so called Deeley gear or Stevart gear as it tends to be known. Study the picture carefully, you will be examined! Stevart Gear by David Goyder, on Flickr You can see that the expansion link is rocked at A an B by a lever coming from the opposite crosshead and not from an eccentric coming from the driving wheel as is the case with outside gear or from an eccentric inside and found on the main driving axle. The advantage (there is one? ) is to remove the need for an eccentric on the inside. This is the lever that rocks the expanion link on mine. IMG_2204 by David Goyder, on Flickr a bit of a mess. It is driven by one of th forked levers in this IMG_2188 by David Goyder, on Flickr Actually the messy lever is from two of three years ago just to show you the issue. Today one of the levers is loose on the pin that holds the expansion link. I now understand this enough to say that the amount of looseness in the expansion link gives the lever that drives the valve on its travel, more than the port size in the valve liner which explains why it suddenly jambs up.It will never go like this!! So I must put on my overalls anddive into that mess to try to extract said loose lever and proabably make a new one. Anybody got a potion to make oneself small!!! And by the way the boiler is a pig to get off, took me two days, it is heavy and akward and to big for me to lift!! IMG_0227 by David Goyder, on Flickr Pass the gin!! Cheers David
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Midland
Elder Statesman
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Post by Midland on Jul 15, 2021 19:14:21 GMT
An update, Found the same thing as above but on the R side this time. The forces needed to rock the expansion link must be quite great hence the bolt amd taper pin. The slot for the taper pin is worn so I will have to enlarge it a little and jam another one in after doing up the bolt. All that boiler off for just that, frustrating! Cheers David
I should add that it must one of the peculiarities of the Midland that wedded to Stephensons in all their locos, lots of them, Deeley was allowed to go this way but they did out perform the compounds to start with. Along came superheating and the game was up, compounding came into first place. I imagine that the CME had too much authourity to do what he liked and crazy ideas came along. A bit like the LMS with Stanier. Tom Coleman designed all his locos, the Black 5 competely, the Princess Royals and Coronations. All Stanier did was to impose GWR susperheating which did not work as the LMS burnt different coal. Only when Coleman raised the superheater temperature while Stanier was in India did the pacifics become successful. Just some thoughts!!!!
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JonL
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WWSME (Wiltshire)
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Post by JonL on Jul 15, 2021 20:06:26 GMT
It will all come together. Best look for any other jobs that need doing whilst the boiler is off!
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Post by coniston on Jul 15, 2021 22:15:08 GMT
Perseverance as usual will win the day for you David, take it one bit at a time and as Jon says look for anything else that may need attention whilst you can get at it.
Chris
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Midland
Elder Statesman
Posts: 1,870
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Post by Midland on Jul 27, 2021 21:06:51 GMT
Hi Chris Was that perseverence or abstinance, by god does the gin help a bit!!! We are ready for a steam test as it works using air. Quite exciting to see the wheels go around more than once. Had to take the bloody thing apart to get at it. A couple of photos! Not much to see really but, IMG_0299 (2) by David Goyder, on Flickr and this is where all the added bits go temporarily IMG_0303 by David Goyder, on Flickr and a poor little buffer beam, IMG_0302 by David Goyder, on Flickr Anyway the next report should be her flashing by at 60 mph (that is 5 in our terms!) Cheers David PS Hope I remember where all the bits go!!!!
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jma1009
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Post by jma1009 on Jul 28, 2021 21:21:54 GMT
Hello David,
I do recall discussing with the late Don Ashton the "scissors gear" as applied to 'North Star' on the GWR as what was to become a 'one off'. It was discarded, as is well known, in favour of inside Walschaerts valve gear because it was very difficult to set the valves.
You have corrected faults found in old parts, but whilst the boiler is still off, might a detailed examination of 'cut offs' and 'lead', etc, be worthy of undertaking - as an on air test is pretty much a very rough and ready test?
Cheers,
Julian
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Midland
Elder Statesman
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Post by Midland on Jul 29, 2021 7:58:38 GMT
Hi Julian Thought of Don when I had this apart! I contemplated taking it right apart to measure up the bit and pieces and try to do an accurate drawing even to the extent of trying to use a simulator to see what happens, but . . . So I have her back together so I can have some fun. I have not really had a decent 'play' since I have had her. First was the blow by in the valves and new rings and then Covid came along and of course I have not really got the valves correct after the new rings. So If I have it right enough now I can contemplate a few minor tweaks to smooth it out as we go along. The big test is to get her into steam shortly and assess!! And I should mention that on both expansion links, the levers that actuate them were loose and are now tight with new bolts, taper pins and clean taper holes if ther is such a thing. So lots to check out before anymore mucking around with her. Cheers David
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twombo
Seasoned Member
Posts: 119
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Post by twombo on Jul 29, 2021 9:44:27 GMT
Thank You Roger for your “misquote” of a “great Man”! Follows, is a quote by another great Man! OUR, great Man!
“Mr. President, I have been informed by Mr. David Bruce that it is your intention to sign a bill conferring upon me honorary citizenship of the United States.
I have received many kindnesses from the United States of America, but the honour which you now accord me is without parallel I accept it with deep gratitude and affection.
I am also most sensible of the warm-hearted action of the individual states who accorded me the great compliment of their own honorary citizenships as a prelude to this act of Congress.
It is a remarkable comment on our affairs that the former Prime Minister of a great sovereign state should thus be received as an honorary citizen of another. I say “great sovereign state” with design and emphasis, for I reject the view that Britain and the Commonwealth should now be relegated to a tame, and minor role in the world. Our past is the key to our future, which I firmly trust and believe will be no less fertile and glorious. Let no man underrate our energies, our potentialities and our abiding power for good.
I am, as you know, half American by blood, and the story of my association with that mighty and benevolent nation goes back nearly ninety years to the day of my father’s marriage. In this century of storm and tragedy, I contemplate with high satisfaction the constant factor of the interwoven and upward progress of our peoples. Our comradeship and our brotherhood in war were unexampled. We stood together, and because of that fact the free world now stands. Nor has our partnership any exclusive nature; the Atlantic community is a dream that can well be fulfilled to the detriment of none and to the enduring benefit and honour of the great democracies.
Mr. President, your action illuminates the theme of unity of the English-speaking peoples, to which I have devoted a large part of my life. I would ask you to accept yourself, and to convey to both Houses of Congress, and through them to the American people, my solemn and heartfelt thanks for this unique distinction, which will always be proudly remembered by my descendants.” –Winston S. Churchill”
Truly.. OUR great Man!
Forgive me, Brothers and Sisters in the mother Country of my Ancestors! I find inspiration daily in Sir Winston’s words! “never Surrender! Never, ever, ever, Surrender!” I will misquote now…. “Never in Human History has So Much been owed, by so many, to “The “One”.
He “Walked with Destiny”!
Mick
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jma1009
Elder Statesman
Posts: 5,900
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Post by jma1009 on Jul 29, 2021 21:40:52 GMT
Hello David,
Setting aside the previous post that has no relevance whatsoever to a discussion of the scissors valve gear, do you not think that further examination of the valve events is a good thing?
I give this a 'heads up' because it is well documented that the full size gear of this type it was difficult to set the valves, and presumably even more difficult in miniature.
Just a thought.
Cheers,
Julian
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Midland
Elder Statesman
Posts: 1,870
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Post by Midland on Aug 1, 2021 20:37:36 GMT
Hello David, Setting aside the previous post that has no relevance whatsoever to a discussion of the scissors valve gear, do you not think that further examination of the valve events is a good thing? I give this a 'heads up' because it is well documented that the full size gear of this type it was difficult to set the valves, and presumably even more difficult in miniature. Just a thought. Cheers, Julian Julian, Yes it would be wonderful to do that but where do I start. I have found the dead centres, put hoses on the drain cock extensions and watched the bubbles and followed the movement of the valves in the Dockstater simulations. I have also watched the frightening pace with which the valve stems move as the piston gets to dead centres and realise that the difference between success and failure is but a quarter turn on the valve stem when tightening up the nut. So when one compares the 4BA pitch as 25 thou and half a turn is 12 thou and lead is . Frightening is it not? I have done my best so far and will see what happens unless you will ride in on your white horse!!!! Cheers David
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twombo
Seasoned Member
Posts: 119
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Post by twombo on Aug 3, 2021 9:44:25 GMT
Please forgive my last, inept post. I got lost in this forum structure and some way leaped forward 21/2 years!
I was reviewing the whole thread to get up to speed. I saw Rogers allusion to JFK. THEN IT ALL “TOOK A JUMP” this motion is very difficult to understand. Is it Stevart? I will do a search on that! Is “ one half turn for .012” based on 4ba thread pitch, the least possible valve adjustment, for some reason?
I cannot see wellin the diagram. It may be my vision issue. I hope not cognitively, a “confabulation” on my part! That is, rather more, a concern of mine.
I ask Your forbearance , please!
Mick
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