Overhaul of a 9F

[Deleted]

The 9F is beginning to look the part again Don, I love looking at your loco as I can see and appreciate all of the extra detail that you've included in your original build. She's a work of art sir...

regards

Pete

[don9f]

Hi Pete, thanks for that.....I have made some good progress the last few days but more gardening is quickly looming!

Cheers Don

[springcrocus]

May 22, 2018 21:18:43 GMT don9f said:

Hi Pete, thanks for that.....I have made some good progress the last few days but more gardening is quickly looming!

Cheers Don

Bah! Know the feeling...

Regards, Steve

[don9f]

A bit more progress to report....

Firstly in common with some of the other BR Standards, the 9Fs have a number of control spindle extensions passing through the cab floor and the cab front. All these have to line up properly with the valve or other item they are operating. In addition there are a number of pipes entering & leaving the cab which all have to pass through and overall it makes fitting the cab a bit of a fiddly job. Annealing all the original pipes, causes subtle changes to their shape, so nothing fits properly again without “adjustment”.

The main manifold on this model is the first casting of one ever produced by Doug Hewson, from the pattern that I actually made. I don’t know if it is the same as those sold today, but this one has some of the flanges, dummy studs/nuts and the auxiliary take off valve cast in and the pipes have to be silver soldered into these items. The flanges on the ends screw in to the body and whilst it looks very much the part, on this model the manifold actually screws in to a threaded bush on top of the firebox, so all the pipes have to be fitted first, the manifold screwed in, then the pipes bent to suit! Not the best way of doing things, but hey ho, that’s how this one is! The real thing of course fits to its mounting via studs and nuts.

As you probably realise, removing the manifold for this overhaul last year therefore meant bending all the nice neat pipework back to a position where the manifold could be unscrewed from the firebox. Getting it to all fit neatly again has been very time consuming and I’ve still not quite finished, but here are some photos of where I’m up to.

Note the original injector steam valve extension spindles re-ended with new adaptors to fit the slightly smaller spindles of the new valves, plus the little support brackets to steady them off the side of the firebox....I never had these originally but thought I’d fit them this time round!



Some of the injector pipework flanges etc. will be very difficult to access once the cab floor is in place, so I made sure all flanges and fixings were sealed and tightened beforehand.

 
Firehole doorgear is fitted, as are the rear brake cylinder and tender brake steam pipes, plus a few other bits like the non-prototype whistle valve and the regulator operating handle.

When I fitted the brake lubricator block, I realised that it almost fouled the LH lower water gauge fitting and due to things being a bit non scale in the vicinity, covered up the shut off lever, which was only a dummy anyway, but now cannot be fitted on that side! It’s too late now to start repositioning everything, so I’ll just have to live with that.



The final photo for this update shows the cab floor temporarily fitted, along with the driver’s pedestal and my old home made dummy Mk6 graduable steam brake valve (new functional Mk6 eagerly awaited from Adam). You can see how it gets a bit congested around the pedestal!



That will be it for a while....hopefully I’ll be able to carry on and get the boiler ready for a steam test before too long. Best to do that before finally fitting the cab, with all that’s still to be fitted, it’s not a 5 minute job to remove it if something leaks or doesn’t work!

Cheers   Don

[Deleted]

Now that's really starting to 'look the business' Don....lovely work and attention to detail sir...

Pete

[don9f]

Thank you Pete....but you should see the “other” 9F in our club. Its builder is well known for the quality of his models and unfortunately (for me), his model of single chimneyed 92150 puts mine to shame!

Your own model is looking very good by the way.....painting is not my favourite job!

Cheers Don

[92220]

As Pete says, looking really good Don. You may not like painting but that looks a pretty good paint job!! You'll soon be pulling passengers!

Bob.

[don9f]

Having escaped from gardening duties the other day for a couple of hours, I was going to fit the cab floor but on close inspection decided that my paint “touch up” of it last year wasn’t up to much and really needed doing again. I stripped all the flaking paint off with Nitromors and gave it a rubbing down with fine abrasive....bearing in mind that it is a fabrication with a few awkward to get to areas.

Anyway, the result was much better and the first photo shows it in Upol primer. Obviously this is upside down and the lumpy bits in the foreground are silver solder, joining two bits of chequerplate together, as at the time it wasn’t available in the right width.



After escaping again, the next shows it in black and all bolted into position on the frames, complete with pedestal and damper control gear.
The depressed area behind the pedestal/damper gear is where the wooden part of the floor fits in between the cab sides and there is another section of chequerplate to fit immediately behind the backhead.



Fitting 10ba screws and nuts to the brackets that support the leading part of the floor structure is a right fiddle....it’s a good job I had plenty of training with Meccano when I was a boy. You can just see some of them above and to the left of the injector water valves.



I’m in the process of fitting the water gauges and am waiting for a glass tube cutter, some 5mm glass and small o rings to arrive, so I’ll post about that on the next update.

Cheers for now

[don9f]

Hi, the water gauges are now fitted, complete with glass, seals etc. You might recall that I had posted a while ago (Sept 2017) about being disappointed with some new commercial ones that I had bought to replace my old original ones, finding them far to "chunky" for my liking. I decided to have a go at making my own, aiming for something not only a bit smaller, but at least looking a bit like the real thing!

Unfortunately I didn't realise at the time that there would be a minor problem later on with other cab details wanting to share some of the same space. Its too late now to start altering things, so I have had to leave off the dummy shutoff linkage to the Driver's side gauge. I copied the full size in this area and made two sets of water gauges both handed the same....if I'd known, I could have made one LH and one RH and it wouldn't really have mattered. Something for the next overhaul!

This was a photo taken last year after producing all the parts:-



These gauge frames are threaded 5/16 x 32tpi and when I made them, I tried to ensure that once each one was tightened into its backhead bush, it was in correct alignment with its partner....Sod's law would normally dictate otherwise that they would tighten in the wrong place. Fortunately this worked out nearly right and to achieve the desired alignment, both the top ones needed to be shimmed out from their bush by one full turn. I used a combination of thin copper washers but ultimately the sealing of the threads is by ptfe tape, so the washers really only fill the gap.

Ideally when the glass is fitted, there should be no contact between the glass and the metal parts. I copied some of the commercial dimensions in this respect and for the 5mm dia glass, allowed for 5.25mm clearance holes in the frames where the glass fits. I turned a piece of metal rod to this 5.25 dimension as a gauge and used it to set the frames in the best alignment I could achieve (sorry its a bit blurred):-





Once happy with both gauges, the glass was prepared for fitting. The cut ends of the glass tube are obviously left sharp which is undesirable, so they were rotated for a few seconds in a flame which creates a nice rounded finish to the ends....the added bonus being that this helps subsequently in passing the tube through the o ring seals contained within the nuts top and bottom.



Talking of nuts, mine are made from 2ba brass hexagon (.324" A/F) and are firstly threaded 9/32 x 40tpi to the full 1/8" depth of a 1/4" dia flat bottomed hole, using a tap specially ground for this. The flat bottomed hole is then extended by a further 1/32" so there is a clean unthreaded section of hole just beyond the thread for the o ring to sit in.

I am using viton o rings that are 6.5mm o/d with 1mm section. They fit nicely in the nut and with the rounded end to the tube, I had no difficulty in assembling the glass, seals & nuts to the frames. Note that for the bottom nuts, I have added a bit of extra material, to give an extra margin for the low water level. This is a feature sometimes encountered on full size gauges.





The next photo shows the finished gauges and you can see the unforseen clash between the LH bottom frame and the brake lubricator block....




Just as an aside, all the small hexagon plugs that close the various passageways through the frames are sealed with Loctite 577 Thread Sealant and were tightened using miniature ring spanners. These are SO much better for this sort of job than open enders and mine came from a well known Model Engineering Laser company and are brilliant for the price....



Cheers for now   Don

[92220]

Hi Don.

Lovely work!! You were saying about the difficulty of fitting nuts and bolts under the cab floor. One trick I use - as long as the screw head is accessible for a spanner, I hold the nut on a little piece of BlueTac stuck over the end of a thin, narrow piece of steel strip. It holds the nut just long enough to get the screw threaded a couple of threads and then I can use a long spanner to hold while tightening the screw.

I'm just drawing up the underfloor cab platform for mine. That photo of your underfloor frame is VEREY handy to see where bits go!!

Bob.

[don9f]

Thanks Bob, my cab floor was built using measurements from 92214 whilst it was dismantled at Buxton.....it’s quite an elaborate fabrication as you are probably aware.
Incidentally I think that the vertical support projecting up off the rear drag beam (diaphragm plate?) on 92134 has circular holes cut in it, not the square with rounded corners type like Evening Star and other later built engines. For interest, do you have any info on this change?

Cheers Don

[don9f]

Hi everyone, sorry there haven’t been any updates for nearly another 3 weeks, but I have just recently returned from holiday in North Wales where I did manage to get a bit of steam in the blood from things like this:-



and this:-



Eagle eyed viewers may notice the Gresham & Craven Mk6 steam brake valve in the cab of this 1992 built loco (Adam?)

Couldn’t help wonder what a Fairlie would be like in 5 inch gauge.....does anyone know of such a model?
The last time I was in that area was in 1967 and I finally got to travel over the Ffestiniog “Deviation” which in a very small way, I helped build all those years ago!

Returning to 9F things, I have fitted the regulator valve and it’s linkage, plus the internal main steam pipe. Photos of some of these overhauled parts were posted a while ago.
Next job will be to fit the superheater elements and connect up to the cylinder steam pipes etc. and I hope to have some more photos to show in a few days time.

A steam test draws ever nearer!

Cheers Don

[mbrown]

John de Bank of the IoW club built a 3.5"g double Fairlie in (I think) the early 1970s - he did an article about it in the ME at the time, I expect Julian would know all about it - and probably even drove it! I imagine it would be a bit of a pig to drive as the fireholes would be at the side, half way along a lengthy loco.... and, if you have the bottom engine working as per the original, the exhaust would go up your nose every time you reached for the controls. I have a vague memory that John experimented with oil firing, which might have made firing easier on the Fairlie, but I defer to the IoW people on this forum for the full details.

Malcolm

[don9f]

Hi Malcolm, cheers for that....I hadn’t seen one of these locos for over 50 years, so didn’t really know much about them but one thing I took note of and talked to the driver about was that they have two independent regulators, although the reversing gear is linked to avoid the obvious! A bit like aircraft dual throttles and I imagine that could be challenging on a model with a central, side access cab as well!

Apparently better than the Garratts on the Welsh Highland (so the driver said), as you can control slipping on one engine, whilst the other keeps working....

Cheers Don

[don9f]

Hi all, well I managed to find time today to do a bit more to the 9F and take more photos. The lighting in parts of my workshop are not very good and even outside, I find difficulty with shadows etc. but anyway, here they are:-

The external main steam pipes were fitted between the smokebox wall and each valve chest. As may have been mentioned before, I used the arrangement as drawn by LW involving sealant and nuts/lead washers. These pipes each carry a check valve for the oil supply from the mechanical lubricators. In practice, I once had trouble with these check valves “blowing back”, so I fitted additional ones at the outlet point from the lubricators, with the ball seating on an o ring and this seemed to solve the problem:-



I had already fitted the regulator valve along with it’s operating shaft, to it’s mounting within the boiler and photos of this arrangement have been posted before, so I didn’t take any more. The valve has to be in place so that the internal main steam pipe can be fitted....as this pipe then becomes “captive” once the superheater header is fitted. It involves 2 gaskets and so on and if I was making it new today, I would probably make a different arrangement that used some sort of o ring seal which would be easier to dismantle in any future strip-down. I thought I had taken a photo just after fitting the superheaters and header, but now I’m posting this, I find I haven’t done! Anyway you get the idea from the photos I have taken....note also the blower steam supply pipe, plus the (enlarged) pipe connecting the wet header to the snifting valve:-



Attention then turned to refitting the petticoat “pipe” and the chimney. The petticoat is a large gunmetal casting and from memory, the external shape involved much filing by hand, to achieve the oval shape! This is then held to the top of the smokebox by stainless csk screws, with the actual chimney just pushed on. I definitely remember that the chimney bit involved some serious filing, no doubt these days such things could be fully machined with the right equipment!








I scraped the soot off the smokebox door and it’s ring and fitted these too. The ring is secured only be being a light push fit into the front of the smokebox....I never even got round to making some sort of “register” to line it up, relying on the Mk1 eyeball each time it was put back after cleaning etc.


Finally a photo of 92167 once again displaying its 8H (Birkenhead) shedplate! I have fond memories of the place when I was a lad and as may be known, it was once home to about 55 9Fs....hard to imagine these days!



Looks like I need to do a bit more painting....

Cheers   Don

[simplyloco]

Excellent! AND at last I can now see all of your pictures!
John

[mbrown]

The grubby smokebox number plate and shed plate are totally prototypical! Looks great.

Malcolm

[don9f]

Hi John, that’s good news, I suppose it was some sort of privacy or security setting blocking the photos. One thing that embarrasses me frequently is how “scruffy” the loco looks in photos....it never looks half as bad for real. When it’s all done, I’ll wipe oil all over it, that’ll make it shine!

Cheers Don

[don9f]

Hi Malcom, of course you’re right and part of me wanted to “overhaul” it, but keep it looking like they did in the times I remember them. I think some of my club mates would frown on that a bit, so maybe I’ll meet them half way?

Cheers Don

[ettingtonliam]

'Oily Rag' is quite the thing in the vintage car world these days - mechanically restored 100%, but bodywork left pretty much 'as found'
Many years ago I recall a chap who built models of construction plant, dozers, cranes etc. Having done so, and painted them nicely, he then left them outside to weather, becoming dusty, dirty and slightly rusty, just like the real thing.