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Member postings for julian atkins

Here is a list of all the postings julian atkins has made in our forums. Click on a thread name to jump to the thread.

Thread: don young piston valves
26/06/2022 08:27:58

Hi Brian,

John is correct.

The first description by Don may be earlier (I haven't checked). See his 3.5"g 'County Carlow' in ME 1969, and "Fabricated cylinders" in ME 1973. The latter describes the non ferrous piston valve cylinders for his 5"g LNER K1/1. His incomplete K1/1 was only steamed and ran a few times when no one else was present apart from Gordon Chiverton whose 'Maid of Kent' tender it borrowed for these occasions. The boiler never had a club boiler test!

Don's personal experience of piston valves 'in miniature' was limited, and he relied on feedback from others.

Note also that at the time and for very many years Don had only a secondhand Myford 7.

It was not until John Mercer (in ME 1987) described the use of fluorosint rings for piston valves that a decent solution to piston valves (and the liners) wearing out and 'blowing' was 'found' for bronze/gunmetal liners and piston valves.

LBSC advocated precision ground stainless for the solid piston valve bobbins/valves with gunmetal cyklinders on his later designs which will also 'blow' after a bit of use or an interruption in the supply of steam oil.



Thread: Cylinder drain cocks
17/06/2022 09:28:45

I use 2 x 10BA nuts locked together.



Thread: Edward Thomas. 5" gauge. Hackworth Valve Gear.
01/05/2022 23:15:21

Perhaps best to wait until the OP has got back from his holiday.

In my view, valve setting must be done methodically and very accurately.

28/04/2022 22:44:29

Hi Duncan,

"If you just set the lap" as you stated bemuses me.

Notwithstanding the above, I recall Simon Bowditch providing some very valuable input to miniature locomotive designs with Hackworth valve gear.

Of note is that Colin (the OP) has yet to respond.

27/04/2022 09:07:42

Hello Colin,

The variable is the amount of 'lap', but starting from the 'lap' being 3/4 of port width, the 1 5/64" dimension for the over all length of the valve is only just a tad more and will be perfectly ok.

Exhaust port width 0.3125" is a bit less than I would use but doesn't affect the maths.

The exhaust cavity on the valve will be 0.5625" with no exhaust clearance (which I wouldn't add anyway).

0.125" between edge of exhaust port and start of steam port.

Steam ports 0.125" wide.

The steam ports do not need to be fully uncovered in full gear; the exhaust should.



Edited By julian atkins on 27/04/2022 09:09:58

Thread: Detroit Hydrostatic Lubricator
30/03/2022 23:55:53

Hi Dave,

If you send me a PM with your email I can send you the articles and drawings referred to.



Thread: 5" Dean Goods valve gear dimensions
30/03/2022 13:36:09

Hi Alastair,

If I am correct that Keith's 5"g 'Dean Goods' for Kennions is as per my 2014 post, then it is a LBSC designed 'Pansy' without the side tanks and with a tender. Same cylinder block, valves below the bores, same valve gear. Top suspended loco links, crossed rods, and rocker arms reversing the valve travel.

If you PM me I can send you via email my own modifications to the 'Pansy' valve gear, which subsequently Don Ashton checked for and approved.



Thread: Original Tich
22/03/2022 10:06:56

Les Clarke's 3.5"g GWR 4-4-0 'County' appeared in Don Young's LLAS magazine. Principally the 2 piece cylinder block. The completed loco was gifted to the GWS at Didcot where I recall seeing it on display.

I don't have any info on the whereabouts of Les Clarke's original Tich or the highly modified Tich built by LBSC complete with wagon.



Thread: Westinghouse pump in 5" gauge
26/12/2021 10:11:43

Sadly, Bob Youldon died 2 years ago, but he had sent me via email attachments his notes and drawings back in 2016.

I can probably work out how to forward them on via email.



Thread: Contacting a forum Member by PM
19/12/2021 22:16:47

Hi Reg,

Phil (weary) has very kindly prompted me on this, and I have now read your subsequent PM.

Can I suggest you post the contents of your PM on here or on the other forum with some of the drawings?

I am very busy in work until the 25th December and I am not even sure if I have the drawings to which you refer and I have no spare time to check until after Christmas.



Thread: loco won't run
11/11/2021 23:45:29

Hi Noel,

You might be right, but personally I have my doubts. Very happy to be proved wrong. I am pretty familiar with LBSC's 'Brit' design in 3.5"g.

As I said, it seems very odd.

11/11/2021 23:43:17

Hi Noel,

You might be right, but personally I have my doubts. Very happy to be proved wrong. I am pretty familiar with LBSC's 'Brit' design in 3.5"g.

As I said, it seems very odd.

11/11/2021 23:43:05

Hi Noel,

You might be right, but personally I have my doubts. Very happy to be proved wrong. I am pretty familiar with LBSC's 'Brit' design in 3.5"g.

As I said, it seems very odd.

11/11/2021 20:09:15

Am I the only one to consider this all a bit odd? Hydraulic test of the boiler for what? To run the loco again, but where? A club track that it's boiler inspector will carry out the test? Yet no club is mentioned.

I could comment on other details provided that also seem odd. You wouldn't need to touch the chassis for a boiler test. All seems very odd to me.



Thread: New locomotive project identification needed
29/09/2021 12:40:24

Looks like a Don Young Railmotor No.3, based upon the S14 class, but with alterations, and the boiler barrel diameter should be 4 3/4" not 4 3/8".

Thread: Injector LBSC type
30/05/2021 22:59:09

As presumably one of the persons quoted on the other forum mentioned, you cannot make a LBSC injector to work except by luck.

There are lots and lots of issues with all of the LBSC designs. He doesn't specify in print how to get the correct annular gap between the steam cone nozzle and start of the combining cone.

You would be better off copying one of DAG Brown's injectors from his book. He includes a table/graph for the annular gap.


Julian Atkins

Thread: Blast-pipe - Chimney Proportions
23/03/2021 22:56:15

Have none of you heard of Goss, Young, or Sam Ell, or Jos Koopmans?

Happily bemused by all this!

I suppose ignorance is bliss.

Apply the Greenly 1:3 and 1:6 tapers if you will. That was first published in 1904. And will only probably work within certain parameters.

Why Greenly should be still quoted on here after the work of Sam Ell and Jos Koopmans especially is quite beyond my comprehension.



Thread: 5" Maid of Kent Build Log
05/02/2021 20:46:54

Hi William,

The late Percy Wood won IMLEC with a Joy valve gear inside cylinder MOK.

If the Don Young Stephensons valve gear version is improved it ought to be equal if not superior to the Joy valve gear version.

I had drives many times of the outside cylinder version and personally I disliked it. Tricky to drive and fire with the sloping grate and leaning over a long tender. But others with different examples had different experiences.



05/02/2021 10:41:00

Hello William,

MOK. Where to start!

For the SR L1 (inside cylinders version) you have a choice of Joy valve gear or Stephensons valve gear.

The Joy valve gear version is regarded as very good, but not prototypical.

The Stephensons gear as designed by LBSC in the late 1940s is awful.

Hence, K N Harris, and later Don Young redid it. The K N Harris version is more of a complete rebuild, and has a peculiarity from memory.

The Don Young version is less radical and I would suggest be considered. See ME 7th and 21st November 1969.

The Don Young version could do with amending in some minor details as there is no suspension offset, and the lifting arm length may be wrong on the weighshaft, and I am far from convinced that the rocker arm bearing is in the optimum position.

As for Joy gear being not to prototype, there are lots of things about MOK that are not accurate, and to start with it doesn't have piston valves, so personally I wouldn't be too bothered about this.

The driving wheels are BIG!



Thread: LBSC 3.5" "Maisie" - steam regulator valve assembly
03/06/2020 01:58:36

Yes, the regulator rod should slide out of the green bit on it's square.

You don't have to undo the red screws at this stage.The valve and linkage will drop down and be retrieved by the wire I specified you must add to stop these bits falling down into the boiler.

Don't remove your '1' and '2'. Don't disturb this assembly please!



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