Having at last reached a significant milestone on the engine, and despite the ongoing health issues being somewhat compounded by an annoyingly persistent chest infection, the pace of the project seems to have picked up a little! Perhaps it is not just some sense of urgency alone, but also an impression that the goal is almost within grasping distance that is generating a bit more momentum ?!
The next major part, with whatever peculiar technique I might manage to decide upon, had been quietly bothering me for quite some time. Any questions, and the many lingering doubts, must however be resolved in the next few days, as I have now fully committed myself with the following action:
I recognised the essential requirement for an easily cut, chucked if necessary, and cut again template for the task. Thank goodness, (and Rod too!) for that splendid old mountboard stuff...
Now I could see the shape of things to come! The route toward the destination may, typically for me, be a convoluted one though?
Nevertheless, having established the fit, the scalpel and saws were applied to some ply...
(and strip wood!)...
The construction does look a bit quirky, or even bodged...? with extra holes in rather odd positions... ?! There is a reason - if that is indeed the word for it?:
The large saddle tank will have to be detachable in order to install and remove the battery for running sessions, so some form of reliable attachment system has to be devised, and using either loose or captive bolts, piano hinges or even draw sliding rails have been considered. Whichever method is finally chosen, there are some awkward fittings and fixtures to confound each theory!
Without any wish to be personally insulting, I am afraid that I feel compelled to mention that the enthusiast and author; Mr. M. Smithers, in what is regarded by some as a seminal publication on the subject of 18 inch gauge railways, unfortunately and unwittingly revealed a quite serious lack of observation skills, and therefore made some presumptive, and notably erroneous statements, particularly about the Horwich locomotives. Amongst them was a description of the "unique" and "unlike their Crewe predecessors" location of the blower valve - up forward and between the dome and chimney. He clearly hadn't looked very closely at the fair number of engineering drawings intended for, and then actually published in his own book, let alone studied any photographs that would contradict that notion. Furthermore, he also appears to have not fully understood the basic and fundamental principals that dictated the original design of the locomotives; that being the method of operation. John Ramsbottom's pioneering little Crewe tramway engines - and the inspiration for Aspinall's later version - were direct replacements for horses, that were primarily worked by a single, experienced "shunter" and a well trained animal. He would walk alongside and could be expected to let go the reins, move forward to change points and then let the beast and it's burden catch up. It is not so surprising then to note that the locomotives were configured to allow a similar way of working - and what might then have been regarded as an "efficient" practice! Why bother with a footplate then? The rather vestigial affairs provided were not much more than an occasional convenience, mainly used as a mount for passing through narrow, restricted spaces, and as a handy way of nipping over the "traces" while in motion. They were perfect for the driver to "pose" on for an official photo as well! There is not only a precious, ancient, and all too brief clip of moving film showing these practices in action at Crewe, linked on WT a while ago, but photos taken in the 1970's of the BR., two feet gauge, internal tramway serving Chesterton Junction PW Yard that reveal a driver on foot while controlling a Ruston LBT diesel and shunting a rake of loaded wagons in precisely the same manner!!
Mind you, to be fair, riding on a heavy engine with tiny driving wheels, hard riding with a suspension barely worth the title, and routinely passing over the flange gaps in standard gauge rails at repeated right angle, or worse, shallow crossings, we may have some sympathy with any driver who considered that no amount of discomfort or additional risk was anywhere near as bad as the alterative ?!
All that academic stuff aside, when the "Lanky" (in around 1902 (?)) decided to improve the water capacity of their eight little engines, in each case the blower supply and globe valve had to be moved aft to, a more sensible, main steam manifold above the backhead position, while a new pipe was then extended over the flat top of the tank on way to the base of the chimney. Large diameter balance pipes were also fitted under both the left and right sides of the saddle, leading aft to the original well tanks.
Just those features alone are downright awkward for a silly old modelmaker who would like a pretend water tank to act more like a motor vehicle bonnet !!
The old fool is also determined (against good advice I should add!) to fit a battery charge indicator, disguised as the pressure gauge, which is mounted on the dome - that itself will be firmly attached to the tank. Fearing inevitable memory loss moments that will occur, all the electrical wiring needs to be kept short and entirely contained within the "boiler" - with an absolute minimum of connectors to accidentally forget about!
A peculiarity of the prototype has provided some sort of answer to all the last mentioned issues:
The original locos' had saddle tanks - unlike the BR bodged and slightly dog eared survivor at the NRM, that were of rivetted platework. The final "closure" of the tanks could only be achieved by the provision of external flanges at one end. This might normally have been hidden from view on a locomotive with a more conventional weatherboard, cab or bunker structure abutting it, but in this case, for either Mr. Aspinall, Beyer Peacock or the Company Directors (?) it was presumably considered to be an unacceptably obtrusive eyesore. Their solution was a slightly extravagant extra bit of steel plate, held in line across the gap for the steam dome with an angle on the inside, and screwed to four lugs on the tank endplates. This plate was close, but not always a perfect fit, especially after becoming knocked about in daily service.
Curiously, when the tank on "Wren" rotted and required replacement in 1953, the Horwich fitters apparently went for the easier option of welding, and for that the technique would surely have rendered the flanging completely unnecessary - yet strangely, they chose to follow the earlier patterns, and luckily for us, retained the wasteful end plate arrangement. Very handy for me and this particular project anyway !!
Mounting this additional plate permanently on the boiler barrel, with the separate, and movable saddle tank snuggling up will provide a secure fitting for a bracket to hold the pressure gauge in an alignment that gives the impression that it is still attached to the dome. The bracket and framework will hold the contained wiring in place, along with the ends - with subtly placed joins - of copper plumbing for the gauge and blower. The narrow bottom of the tank will also be similarly fitted to the boiler, thus holding the balance pipes too.
It all seemed to be win, win... until; Uh, oh!...
With the tank end securely fitted in place, the reversing lever forward travel was compromised. It wouldn't quite latch any more !!
I had been so very careful with all the measurements, and was sure that I was within acceptable tolerances. I went back to reference pics, and closely examined images of the original locos - and there it was: The evidence was perfectly clear.
The Horwich draughtsman responsible for the modification work had cocked it up too, so many years before I came along !!
Proven, official Horwich remedy; multiplied eight times; belt the edge of the tank with a big hammer and make a dent, then the lever
will fit !!
It rather looked like I would have to do something similar, but I was not so sure about that though. While genuinely prototypical, I fear it would look too much like seriously bad model making. After a bit of thought, I decided on a naughty compromise. Noting that I had already made a slight error - in that the cut-out in the boiler was not quite square anyway, pulling the glued and screwed plate back off and adding a slightly tapered gasket not only corrected that, but also moved the awkward (and previously correct) side forward by about 1mm. In the overall scheme of things, having a finished tank, perfectly square, but just 1mm short will really not be noticeable, and a carefully designed and weathered "dink", rather than a full blown whack on the tank edge might satisfy the purist in me, and look a little less like a mistake, and more of the expected wear-and-tear damage ?!!
Damn close innit?! but I am a lot happier with that now !
Boiler cladding, a bit of filler on the quadrant bracket and several coats of thick, black paint should hide the gasket ?
The beauty of using ply for a tapered gasket is being able to clearly "see" and check the amount of material being removed as the laminations are cut back and revealed.
In my slightly about face way of working, I reassembled everything - just to make absolutely sure - then took it off again to fit the decorative screws and dummy "rivets" !
Then forgot to take pictures of the completed article - now all back on again and awaiting it's first coat of that lovely, rich, "Ivory" black paint !!
Shaping and fitting the tank bottoms is the next challenge on the diminishing to-do list.
Pete.