Final stages of “Jinty”

[don9f]

Hi, as hinted at a couple of times I suspended work on the overhaul of the 9F (in July 2018) and instead have been working on the completion of a Martin Evans “Jinty”, started around 20 years ago by myself and my stepson. For all the usual reasons, this project got put on “hold” for a good number of years but the good thing was that we had bought all the castings and the boiler kit in the early days!

I have always liked these little tank engines, known as “Jinties” or “3Fs” and having been brought up in the Birkenhead area, used to see them working from most of the sheds we used to visit in the area. One particular fond memory is of one pulling a number of out of steam 9Fs out of the shed at Birkenhead and onto the uphill gradient up the yard. So far up, the cavalcade stopped and with much slipping and noise, the whole lot slid back down where it had come from, with the Jintiy’s wheels still desperately trying to go forwards! Happy Days....

Anyway, I have to confess that apart from a short video I linked to in the “What I’ve done today” thread back in January, I haven’t taken a single photograph of it at all and am beginning to feel a bit guilty at not joining the various fascinating build threads that are ongoing on this forum.

A recent request for info on the Fowler type of vacuum ejector that would be fitted to these engines has resulted in some great scans of relevant photos and drawings and I am indebted to the members who responded, particularly Malcolm and David....but Thank You all very much!

I think I have now sorted out how to make such an ejector in 5” gauge and intend to start on it tomorrow and to start taking some photos as I go. The loco isn’t quite finished yet but it is at quite an advanced stage and as I strip it down for painting and then final assembly, I could take photos of the various parts of it and how it all goes together, if this would be of interest? It is basically built to Martin Evans’s design, but with various alterations and additions to enhance its appearance where possible, bearing in mind that the basic running chassis was built many years ago.

The chosen identity is 47447, a resident of 8H Birkenhead Mollington Street in the 1960s and withdrawn from there in Dec 1966.



Please let me know

Cheers   Don

[mbrown]

I have loved Jinties ever since I was invited into the cab of one at St Pancras, aged 4! I had a distinct memory that the fireman pulled the firebox door downward to show me the fire - and this perplexed me for years because Jinties I saw later on when shed-bashing had sliding fire doors. When I got the LMS Loco Profile my infant memory was vindicated as it showed that some had the earlier Midland-type door which dropped down to open!

All of which is a long-winded way of saying that I would love to see any photos and notes you may be able to post.

Malcolm

[springcrocus]

Sept 29, 2019 21:05:19 GMT don9f said:

I think I have now sorted out how to make such an ejector in 5” gauge and intend to start on it tomorrow and to start taking some photos as I go. The loco isn’t quite finished yet but it is at quite an advanced stage and as I strip it down for painting and then final assembly, I could take photos of the various parts of it and how it all goes together, if this would be of interest? It is basically built to Martin Evans’s design, but with various alterations and additions to enhance its appearance where possible, bearing in mind that the basic running chassis was built many years ago.

Please let me know

Cheers   Don

Of course it would be of interest. Seeing the parts and how they go together often gives someone else that "Ah ha!" moment, especially considering the poor quality of and lack of detail on drawings provided for model engineers. Plus hints, tips and workarounds are always welcome.

There are far too few participants on this forum, please be encouraged to continue this thread. I, for one, will follow it.

Regards, Steve

[barlowworks]

Hi Don

I too would love to see a build thread. My memories if the Jinty go back to when I was a small child and Father Christmas brought me a TT gauge train set with a Jinty goods train. I seem to remember it had a very improbable top speed.

Regards

Mike

[Midland]

Hi Don

Me too! It will be a very quiet confession that I have a set of frames, wheels, valve gear, rods etc secreted away in my work shop and I add to my cache when frustrated with the other ones. Actually most of the valve gear if the same or similar to the Princess of Wales so making two off with one setup seemed a good idea!
Cheers David

[ilvaporista]

I started Molly over 40 years ago and it's sat there for the past 35 looking at me. I'd love to see a 5" version completed. It might even stir me in to action.

[lparris]

A build thread would be great! Jinties are one of my favourite 'little locos'!

[Midland]

Don
No excuse, the masses have spoken, get building. Mine will be from the 2441 class so I can paint her red!
D

[don9f]

Well thanks everybody for responding, I'll try to keep the updates coming, but apart from anything else that might interfere with progress, I'm waiting for a knee operation, haven't got a date yet but it could be anytime!

The ejector is very prominent on the driver's side of the smokebox on these and other Fowler locos and in particular on the Jinties, the arrangement of the ejector and its exhaust pipe incorporates part of the handrail on this side. Another common feature on Fowler locos is that the small ejector is supplied with steam from a valve on the backhead in the cab, whereas the large ejector steam comes from a valve mounted close to the ejector and operated by a pull rod from the cab! In both cases, the steam is supplied as required via internal copper pipes from up in the dome. The real engines do not have a manifold.....but the model does. I may have to position things slightly differently due to the boiler feed clacks being in the vicinity. Again on the real thing, the clacks were backhead mounted.



Made a start today on the main body of the ejector. First thing was to find some chunks of metal to make it out of, so lets see if I can turn some of this:-



into one of these:-



This is a crop of a photo kindly sent to me by David and is of an ejector fitted to a left hand drive loco. The one I need is for a right hand drive, so will be a mirror image of this....I will be constantly reminding myself of this when looking at the various drawings I've also received from members of this forum.

I'm not going to show every mundane machining operation....its all simple stuff and all done by hand (don't have cnc, 3D etc.), although there's a fair amount of headscratching, deciding how to do it so the thing at least looks realistic. The next few photos show how I have used a 2mm ball nosed slotdrill to try to avoid any unrealistic sharp internal corners, as obviously the real thing is a casting. External corners will be filed.





And here the first two bits silver soldered together:-





A bit more filing tomorrow, make the flange that goes on the end and start on the various dummy hexagon headed caps that fit in some of the holes.

Cheers   Don

[don9f]

Sept 30, 2019 6:39:18 GMT mbrown said:

I have loved Jinties ever since I was invited into the cab of one at St Pancras, aged 4! I had a distinct memory that the fireman pulled the firebox door downward to show me the fire - and this perplexed me for years because Jinties I saw later on when shed-bashing had sliding fire doors. When I got the LMS Loco Profile my infant memory was vindicated as it showed that some had the earlier Midland-type door which dropped down to open!

All of which is a long-winded way of saying that I would love to see any photos and notes you may be able to post.

Malcolm

Hi Malcolm, the very first steam loco cab I ever went into was a Jinty....the Station Pilot at Chester General one day. I’ve only just remembered that fact after your post!

Cheers   Don

[don9f]

Sept 30, 2019 8:55:48 GMT Midland said:

Hi Don

Me too! It will be a very quiet confession that I have a set of frames, wheels, valve gear, rods etc secreted away in my work shop and I add to my cache when frustrated with the other ones. Actually most of the valve gear if the same or similar to the Princess of Wales so making two off with one setup seemed a good idea!
Cheers David

Hi David, firstly thank you very much for your help with the drawings and photo....(must get my own email fixed)!

I can vouch for the fact that if built as per the drawings, the valve gear does actually work! I think Julian had a suggestion of a slight improvement by adding suspension link offset, but as I have found, it runs on air very well.

Cheers   Don

[ianmcgoo22]

Hello Don, it's great to see this. I'm a new forum member who is looking forward to seeing your progress. I just started building a Jinty of my own in 7 1/4" gauge. Maybe I can even start a build thread of my own once I have some parts worth showing!

[Midland]

Don
Julian can comment on what I am going to say but I think the problem with Martin Evan's Stephenson gear is that it works fine in full gear but does not like to notch up. The changes 'we' (yes quite a few helped) made to the PoW was not over come this issue. I am not sure if it worked due to my incompetence. I did run the Jinty through Don Ashton's system, will try to find it and advise but any changes will be minor and to the suspension link offset as you say. What fun, what is a collection of Jinties, a Jungle perhaps.
D

[don9f]

Hello, yes it would be good to see a 7 1/4“ Jinty build. I started this 5” one a long time ago and if I was starting again now, I wouldn’t use Martin Evans’s design as although it looks reasonably good and I don’t think that there is any doubt that it will work, there is scope for a lot of improvement to scale appearance and to get even some basic dimensions correct....but that’s too late for me now!

Cheers Don

[don9f]

Oct 1, 2019 8:41:54 GMT Midland said:

Don
Julian can comment on what I am going to say but I think the problem with Martin Evan's Stephenson gear is that it works fine in full gear but does not like to notch up. The changes 'we' (yes quite a few helped) made to the PoW was not over come this issue. I am not sure if it worked due to my incompetence. I did run the Jinty through Don Ashton's system, will try to find it and advise but any changes will be minor and to the suspension link offset as you say. What fun, what is a collection of Jinties, a Jungle perhaps.
D

Hi David, I have run this one on air and it does actually notch up quite well considering....will be interesting to see how it performs on the track under steam.

Cheers   Don

[Deleted]

lovely looking loco Don, I've seen Tom Parman's which is also a lovely model of the prototype, looking forward to seeing your progress..

Pete

[delaplume]

Hello all,

Don't forget the one at the SVR.............Currently in The Engine House awaiting renovation

www.svrwiki.com/LMS_Jinty_47383


www.railadvent.co.uk/2018/05/lms-fowler-jinty-steam-locomotive-class-class-information.html



These might be of use ??-------->

[Midland]

Good news Don

[don9f]

Hi, had a good day today but inevitably didn’t get as far as I had hoped. Made the large ejector steam inlet fitting, plus the flanges (twice!) that connect the ejector body to the exhaust pipe.
The flanges were coordinate drilled on the milling machine, then sawn out and profiled on the linisher. Holes were tapped for 1.2mm studs on the flange that attaches to the body, clearance holes in the other.
The first pair went a bit wrong so had to start again!



Parts silver soldered in place ensuring that the flange was at the correct angle:-



Next step was to form the offset bend that forms the transition between the ejector body and the exhaust pipe that incorporates the 90 degree elbow into the smokebox. The required 5/16” offset needed to occur over a relatively short length and I didn’t think I would be able to actually bend a pipe like this. Instead I machined a length of brass to 7/32” dia (scale 2 1/2”), drilled a 5/32” hole up the middle then, one at a time, sawcut about 85% through, closed up the cut which caused it to bend a bit, then silver soldered back together. Three such cuts got half the offset, so turned it over and three more brought the pipe ends parallel again. A bit of work with files and emery produced a fair result.
The second flange was silver soldered onto this pipe, again ensuring the correct relative angles etc. As it is at the moment, the pipe will be shortened somewhat before the next section is attached. The offset is needed to maintain the alignment of the two parts of the handrail that form part of this assembly....look carefully and you can see the joins:-







Cheers for now   Don

[jma1009]

Hi Don,

You ought to be able to make the vacuum ejector to work?

MalcolmB has my analysis of cone sizes from all the published designs, and their details, plus my own. I might have also posted this on the forum some years ago.

I would consider the correct suspension offset for the expansion link to lifting link to be something well worth incorporating, as was shown with Martin Evans' 5"g Princess of Wales design for David G (Midland) as a number of us this ran this on the computer simulator and I then did the same with Martin Evans' 5"g Jinty.

Cheers,

Julian