7mm On Heather's Workbench - a baby Small Prairie

Discussion in 'WR Action' started by Heather Kay, 2 August 2017.

  1. Steph Dale

    Steph Dale Western Thunderer

    Or screw it in from above?

    Pencarrow likes this.
  2. Heather Kay

    Heather Kay Western Thunderer

    All sound proposals, and the latter one sounds favourite at the moment. :thumbs:
    Malcolm Trevena likes this.
  3. Bagpuss

    Bagpuss Active Member

    A plain Pin with a head captive in side the loco and a small hole for a pin would work. A brass screw with a plain shank could be cut down to make a sutable part. Just a suggestion.
    Heather Kay likes this.
  4. Heather Kay

    Heather Kay Western Thunderer

    Thanks Bagpuss!

    I’ve worked out a solution based on my skills and materials at hand. I hope to have an update tomorrow.
  5. Heather Kay

    Heather Kay Western Thunderer


    I didn’t get a lot done yesterday. Essentially, I reworked the bolt fixings for the pony trucks so the nuts are now captive on the trucks. That means there’s no likelihood of a nut detaching itself in service. The rear, however, still presents a problem.

    Having adjusted the weighshaft casting so it fitted in place with the spacer, it became obvious the cylinder lever will seriously impede truck swing. I tried filing down the upper side to offer some clearance, but it rather looks like the lever must be removed. There is certainly no way I can fit the steam cylinder and attach it to the weighshaft that will avoid blocking the pony truck.

    I’m not keen on removing details, but I can’t currently see how the pony truck will swing with the lever in place. Perhaps a temporary lash-up might be in order to test on the track before I commit to amputation.
  6. Heather Kay

    Heather Kay Western Thunderer

    Road tests confirmed the steam cylinder lever had to be sacrificed. It’s lost in the murk, hidden among clutter and hopefully won’t be missed.

    Anyway, where was I?


    Saddle retaining nuts. I was all set to glue a cast part in here. I had one of those "thinks" moments as I drifted off to sleep where I realised the casting would double the thickness of the saddle plate. There were already holes etched in the plate, so I dug out my dwindling stock of 16BA nuts and carefully soldered them in place. Ideally, they should have had short studs as well, but a smear of filler will have to suffice before painting begins.


    Apart from the smokebox door, the casting for which I am not entirely convinced by at present, I think that’s about all the fiddly details for the front of this model. Ah, yes, vacuum brake pipe… I rather think that might go on after painting, but I will consult on that.


    The rump has had the lamp brackets and tool hooks fitted. Again, the vac pipe could go on, but there’s lining round the rear panel, so I suspect it needs to go on after painting.

    Time to think about the backhead again, then.
  7. simond

    simond Western Thunderer


    DLOS posted some pix a while back, I believe, in which he showed a lug silver soldered to the pipe, and subsequently screwed to a tapped hole in the underside of the footplate.

    Might need a stud soldered on the footplate at the front as you can’t drill & tap the footplate, where it would show.

    Means the pipes can be easily and firmly fixed after painting.

    It’s one of those ideas I ought to try...

    Rob Pulham and Heather Kay like this.
  8. Heather Kay

    Heather Kay Western Thunderer

    There are definitely times when the mojo just wanders off and refuses to play. Add in external factors getting a body down, and, well, you know how it goes.


    I finally settled to the backhead. The sum total of most of a day there. It’s not that bad, but acceptable for tucked away in the cab and hidden behind a couple of crew figures.
  9. Dog Star

    Dog Star Western Thunderer

    Um, three steam cocks on the fountain with large diameter pipes heading south.... I think that the centre tap on the fountain ought to have a blanking plug, that is unless you have a reason to believe that these engines had an exhaust steam injector.
  10. Heather Kay

    Heather Kay Western Thunderer

    Well, it ain’t coming out now. Well, not right now. ;)
    fenman, Ressaldar, Genghis and 2 others like this.
  11. Dog Star

    Dog Star Western Thunderer

    I have on good authority that 3 has become 2. Come on Heather, you know we all like pikkies :thumbs: .
  12. Heather Kay

    Heather Kay Western Thunderer

    Sorry for the delay, Graham. Life impinged a bit. All better now, at least in this corner of the cosmos anyway. I haven’t been altogether certain about the rest of the cosmos for a while, but there’s not much I can do about that right now.


    The centre feed tap area was excised by deploying a piercing saw blade in its general direction. The union will have to remain, but I suspect that was often the case anyway, just plugged with a suitable, um, plug. As ever, some pipe runs are rather notional, heading generally somewhere.

    I’ve been worrying about the safety valves. I have the castings from the JLTRT super detail kit. As I am not fitting the top feed cover with the bonnet, I have to find some way of levitating the valve bits so they are in the right position within the bonnet itself.


    I started by attaching the valve castings to a small circular brass plate. Then I found suitable telescoping brass tube and soldered one within the other. The smaller diameter fits into the hole etched in the boiler, the larger one supports the valves on their disc.


    Like this. I may end up gluing the valves in places or using low temp solder. I don’t want the little beggars dislodging themselves again after the struggle I had getting 'em to stay put in the first place!


    Here's what it should like like when I’m done. The bonnet, being a shiny brass thing, will be left off until painting is complete. Contemplation is being made regarding two fixing bolts, which appear in most photos holding the bonnet in place.

    While I have your attention with this image, may I point out the rather messy join between tank top and boiler? Now, later in life, a steel plate was formed and placed over this area to prevent water sloshing down the gap during tank filling operations. I’m seriously considering that this plate may have been in place from new, and if it was then I’ve saved myself a lot of filling and sanding in that messy join. Again, lack of information about what goes on up here back in the 1900s is leaving more questions than answers. Perhaps the WT mega brain might weigh in on the idea while I set about fixing the safety valves in place, and more cab detailing.
  13. simond

    simond Western Thunderer


    Telescoping tube...? for shame, you have a lathe and the nous to use it! Actually, the result is indistinguishable, so carry on...

    On the other point, why would anyone care about water sloshing down betwixt tanks & boiler? Fireman breaking ankle, different question (even in those days).

    Dog Star likes this.
  14. Heather Kay

    Heather Kay Western Thunderer

    Ha! Indeed, yes. Sadly, the lathe lives out in the cold shed/workshop. I’m nice and warm cuddling my soldering iron indoors.
  15. simond

    simond Western Thunderer

    Ah, yes, laser, big lathe & milling machine likewise. I do understand. Too ruddy cold!
    November, coat everything in WD40 and retire indoors...

    Treat yourself to an old Unimat 3. It’s Christmas. They’re a bit like a cat, compact, self contained, and like the warmth.

    Not much on eBay today...

    3 LINK and dibateg like this.
  16. Yorkshire Dave

    Yorkshire Dave Western Thunderer

    Would there have not been a rim around the entire tank top to prevent the water sloshing around?
  17. Heather Kay

    Heather Kay Western Thunderer

    From a practical viewpoint, that would be undesirable as it would trap water and potentially lead to corrosion. I’ve not seen an inner rim on any GW tank engine, or indeed those from other companies.


    This is the baffle plate I was considering. Obviously, from the top feed and tons of random scrap on the tank top, this is quite late on in the life of this particular prairie. Note what I assume is a drain hole in the front left corner of the left tank.
  18. Bagpuss

    Bagpuss Active Member

    Love the detail must be a nightmare fitting all that to the backhead.
  19. Heather Kay

    Heather Kay Western Thunderer

    There’s a certain logic to such things, especially where the GWR is concerned. It also helps to have photos that can be followed.


    There’s been little progress, what with one thing and another. My general Scrooge-like attitude to this time of year hasn’t really been helped by what appears to be the self-immolation of the rest of the world. Anyway, head down, soldering iron on.

    I decided to assemble the cab steps. I’ve been leaving them off as they tend to be vulnerable to damage. As it turns out, these are quite tough, aided by a nice thick strip I added up the back as reinforcement. I’ve spent a bit of time cleaning things up, too, which is always a good way to find loose things!

    I have decided to go ahead with the tank top baffles. They solve more problems than they cause, so I can’t see any reason not to fit them.
  20. Heather Kay

    Heather Kay Western Thunderer

    Small things today. I was investigating whistles, but inevitably the eye strays. I noticed something about the cab handrails. I ought to stop looking at photos, because I keep finding things. Actually, what I really should do is deeply study photos before I start the job!

    Now, I had blithely installed turned handrail knobs for the horizontal rails in front of the door openings. That’s not what was done on the real thing. So, out came the knobs, and I was left with holes far too big for the 0.7mm wire I will use for the handrails.


    The real thing, I think henceforth to be known as RT to save typing fingers, had bent rails with small circular plates. I started out by soldering some scrap etch behind the cab sides to cover the holes. I’d drilled said holes 1.2mm to take the knobs, and luckily I have brass rod of the same diameter in stock. Rather than drill right through the plates, I fitted the rod in the hole and applied solder. Happily, things were firm, so I clipped the rod off as close as I dared. As I set about cleaning things up, I realised I didn’t need to file the rods down to the actual cab side. Leaving them slightly proud meant I could simulate the RT's plates, which would only need drilling out to take the wire handrail.

    Only later did I think I could have used suitable brass tube stock for the job. :oops:


    Still, it’s done now. Happy with that. So, whistles.


    The RT has a triangular bracket, bolted to the firebox crown and through the cladding, which supports the whistles. I let the noggin think about how to replicate things in a way that was relatively simple to achieve. In the end, I drilled a hole through the firebox, soldered in some wire as a support, then fashioned the triangular bracket from scrap. With a little fiddling, the cast whistles were fitted adequately.

    Before anyone says, yes, the whistles are the right way round and did have straight pipe runs into the cab front sheet. I’ve checked numerous early photos and they all show them in this order, rather than the usual way. Later in life, the whistles were swapped around to the more familiar order, and might well have ended up with the characteristic swan-neck pipework and shields.

    I suppose I should contemplate those tank top baffle plates now.