Finescale - of a sort?!

[Peter Insole]

The brief outage notwithstanding, I'm afraid I have been doing more worrying brass and solder rather than writing again!

A little bit late in the day, I have collected a fair few photographs of progress to share now:

The straight connector and one of the nuts previously mentioned would prove to be almost perfect for the task...



A couple of small, rubber discs from some pipe end stops will hopefully provide material for the valve seals later too?!

I have shifted from the original design slightly, in that the thread for the lever cap is on the exterior of the barrel, instead of being on a narrowed section. Using the existing nut and leaving a remnant of the matching thread seemed to be a slightly easier option, as well as providing a bit more clear access for later operations?

While I was still considering the best way to proceed, a start was made on the cap itself by filing down the nut and chopping a bit more off a remaining stub of another old donor 10mm coupler:




I have left the inner ring section rough cut for the time being, as I want to solder that, whatever I can find for a hollow centre fitting, and the operating lever clevis in a single, messy operation!

The symmetrical coupler barrel has a reduced diameter pipe stop section in the centre, beneath the former hex, which I felt could be handy for pressing a separating barrier plug into - but that turned out to be a bit of a fiddle:



It did make drilling the apertures for the two vertical tube connections rather a nether clenching exercise... but I got away without any serious mishaps, or missing bodily bits!!

Making a really tight, press fitting plug to fit a hole with an unspecified, and difficult to accurately measure internal diameter required an amount of trial and error... plus a fair wind blowing in the end.




It might not look like it in the last image above, but the plug was sufficiently snug to require a bit of gentle "persuasion" before it settled in the correct position.

I wanted this essential barrier section to hold firmly in place during subsequent soldering up of the two, vertical branches and the front end fitting to come later.

Not only was working out the appropriate order of shaping down, drilling, tapping and cutting the branches tricky and troubling enough...



but on the lower, feed section, I was down to my very last bit of brass hex of the right size in the box...!



Wow! There really was just enough length to spin the shaft to shape when the piece was held in the chuck jaws - so not a millimetre to spare for any errors there!

I will admit that I am somewhat reluctant to order any more brass sections, particularly bearing in mind that I am now so close to completing all the plumbing jobs, that it would a shame to end up with any new lengths of odd size materials. for the sake of a single part!



By the way, the vee shaped cuts filed in before separating the pieces from the stock bar are necessary to fit with the sections left open above and below the centre plug - and having those angles inside the barrel would also provide a flat surface to commence drilling the connecting airways.

I felt it was preferable to drill those airways after soldering up, rather than finding that the angle might be slightly too steep, and then having difficulty trying to clear the tiny holes again of any runaway solder?!

There are more pics and words to bring this bit up to date, but I will save them for later!

Pete.

 

[Peter Insole]

It was a bit of fun trying to ensure that the cruciform remained reasonably square during soldering up, and I did have some trouble with solder not flowing quite where I wanted it - requiring a second dose of flux and waft (or perhaps more accurately a blast) of heat to make sure that the plug was thoroughly airtight all round the edges!



The view above was taken before cleaning up the excess solder, while the two below show how the angles act as both a shaped fillet, that doesn't intrude too much into each chamber, and as previously mentioned, would then provide one, small, flat section for drilling an angled passage connecting with the main column bores at top and bottom.



Once again, I was so busy faffing about with it all that I quite forgot to take pictures of the new holes, so the best I can do is describe them! The front chamber (upper view) has the inlet hole leading down into the branch with the hex and male thread, while the rear chamber (lower view) has the outlet hole leading upwards into the short, stubby, top branch (female threaded for the whistle).

A 2.5mm (max. dia.) valve rod and larger seal should (hopefully) hold the air in the front chamber, and then when pushed in against a spring, allow air to pass through the 3mm hole in the plug, thence into the rear chamber and to atmosphere via the screaming fipple!

That's the theory anyway! I still have absolutely no idea if it will work... but the learning curve is a steep and rather adventurous journey!




Ah well, if it doesn't, I suppose it will still be as a golden ball, sitting pretty and surmounting the glorious dome?!

To bring the tale up to date; I have now soldered in the front ring, and more or less sealed the fate of the front end. Any alterations there are by no means impossible... but I fear it would be very easy for me to get the whole thing in a terrible mess when attempting to sweat any part back off!



It is all a bit tight in there, as the maximum diameter of the valve, (to fit against the plug) is 6mm, so I had to drill and tap the hole in the cap at an awkward M7. This also was at the maximum to allow the valve to be fed in, while still leaving just enough metal all round the cap for a hex screw head to finally seat and seal it up.



I found a handy little fibre washer that was exactly the right size for the whistle joint, but only after screwing it fully home on the valve body I discovered that one, or both of the hand cut threads was on the wonk!

Damn it and sigh!

We will just have to imagine that the exalted object copped a wallop at some time on it's host's travel on the lines around Horwich Works... (probably not a particularly unlikely scenario?) and that it has never been quite as straight as it's fellow bellowers ever since!!

Pete.

 

[timbowales]

Pete, I am in awe of your brass bashing, as usual! Wonderful stuff and don’t worry about the wonkyness, that’s just a little bit of character

 

[simond]

The “Screaming Fipple”.

Would this be some kind of Hammer Horror 1970’s vampire-like monster, or an ideal name for some kind of whistle-based folk band?

 

[Peter Insole]

Ah, I was just in a silly mood last night, as well as getting bored with typing ordinary words!

Trying to be as poetic as I could manage, I thought of an alternative that I was quite pleased with... was utterly convinced that I had inserted it... did a read through just before posting... and spotted a peculiar, empty space in the text. (?!)

For the life of me, I could not remember what the little gem was... so "screaming" was an act of frustration... being as I was, by that time, dog tired and just wanting to click post before heading off to bed!

Pete.

 

[simond]

No excuses, it’s exquisite!

 

[Peter Insole]

I am still not quite sure of the best way to progress making the valve gland and operating rod sufficiently airtight when closed. Fitting a Schrader valve looks like an option, and with that in mind I picked up a small pack of spares (working out at around 50p each!) to have a play with. Fortuitously, and according to my original plan, I had drilled a 3mm hole through the partition in the valve body, while the Schrader valve spindle is 4.35mm at its widest point, so opening out and tapping should not be a problem. It would however require the special purchase of a specific, 5V1-36 tap... for just one solitary job... and for which there is no guarantee that it will actually work in practice?!

In the meantime, and with a decent spell weather promised at last - along with the prospect of being able start tackling a huge backlog of track maintenance tasks, I was quite keen to get the main, wooden (sorry Mr. Ramsbottom!) safety valve finally fettled and fitted!

The big idea for this was to use three steel strips, drilled and bent to form a tripod support within the dome, thus providing a rigid mounting, as well as leaving just enough room to pack a small air reservoir in the space:



It took me a fair amount of effort to cut and shape up two flange "hoops" out of ply sheet to fit really snugly over the valve stem - which incidentally, as it was not practical to fit in the drill chuck to rotate, had to be rounded as accurately as possible by hand and eye alone!

After setting out and drilling six stud holes through both flanges, plus chiselling a slot in the top of one to allow the insertion and lodging of a short fillet, as per the original castings, below the whistle branch.




I prefer to use, for better or worse (?) "Resin W" type wood adhesive for such jobs, and so far it has proved to be excellent at grabbing quite quickly, before going on to form good, sound joints.

Regrettably, it was only after gluing it all up and inserting the aforementioned fillet, that I discovered a very slight misalignment. Admittedly, it wasn't by very much, but it was totally unacceptable when viewing the whole mount, with it's distinctly geometric pattern of studs, from the all important, engine driver's position!

The glue had shifted beyond the grab phase... and even though it was not remotely cured, removing and resetting the double flange was only achieved by the use of boiling water straight from the kettle, an awful lot of grunting, and then cleaning up a dreadfully gooey mess!

Next, I needed to drill a big hole through from the underside of the saddle tank and the twin layered MDF base of the dome.



Great, good fortune smiled upon me here; as I had already drilled a central bore through the layers for accurate alignment of the dome, and that hole was the perfect size for the saw guide bit! The largest tool I had available also neatly cut just inside the four existing dome fixing screws!

Phew!

It took me a little longer to find some suitable steel for the tripod legs.



I found my last, well buried offcut of sheet eventually, but cutting out three more strips this time proved that either my much abused saw blade was getting blunt, my files were becoming dull, or more likely it was me losing my edge?!

After a load of bashing, several minor bruises, and at least two rounds of blood-letting later:



Gosh, I was glad I had chosen to only do three legs! It took an absolute age to ensure that the valve stood vertically, and at the right height.

It was a bit like sawing a shave off a chair leg that won't sit on the floor without wobbling... only to find that it still rocks, and needs a little bit taking off the other three! In the end, indeed if at all, you end up sitting with your knees up under your chin, and only just able to see across the dining table!

After an unimaginable faff of individually flapping legs and falling nuts, the whole shebang was finally bolted in place:




Despite all the fuss, it is still not quite in the middle - as the eclipse effect attests.

I had quite enough, so it can can jolly well stay like that for time being!



Incidentally, on the prototype examples, some had a metal ring lodged under the valve flange, overlapping the gap between it and the dome cover.

Such a fitting could be used to hide my own error and irregularity, but just to be wayward, as ever, I would rather leave it open.

On nice sunny operating days, the varnished black saddle tank and dome gets terribly warm inside - and along with heat generated by the motor and resistances in the controller directly beneath, some of the paint finish is already showing signs of tell tale blistering. I think it might be wise not to restrict any more of the excess therms gathering than is absolutely necessary?!

Pete.

 

[Yorkshire Dave]

On nice sunny operating days, the varnished black saddle tank and dome gets terribly warm inside - and along with heat generated by the motor and resistances in the controller directly beneath, some of the paint finish is already showing signs of tell tale blistering. I think it might be wise not to restrict any more of the excess therms gathering than is absolutely necessary?!

What it needs is a fan installed at the base of the chimney to draw the air through the firebox, over the electrical gear and exhaust it through the chimney.

 

[Peter Insole]

Bang on Dave... but then might it start sounding a bit like an old "Shenfield" quietly humming away while standing at platform 16 on the East Side?

Pete.

 

[Rob R]

Bang on Dave... but then might it start sounding a bit like an old "Shenfield" quietly humming away while standing at platform 16 on the East Side?

Pete.

And what is wrong with that?

 

[Yorkshire Dave]

Bang on Dave... but then might it start sounding a bit like an old "Shenfield" quietly humming away while standing at platform 16 on the East Side?

Two for the price of one - cooling the 'steam' loco electrics and some nostalgia for the old Shenfield EMUs.

I should have mentioned you could also place a 'dry ice' tray above the fan in the chimney to provide pseudo smoke .

 

[Peter Insole]

Absolutely nothing Rob... indeed, I would love to hear that (sorely missed) sound again... but perhaps not emanating from a representation of an 1880's steam locomotive though?!

There has been some previous discussion around here on the various benefits or difficulties of installing a rudimentary cooling system, but the subject had stalled on the points of battery draw - and noise generation! All full size engines gently rumble, gurgle, bubble and occasionally hiss when stationary in full steam, let alone the very individual "voice" of their essential blowers. Finding some way of making an electric fan and ducting produce acceptable tones is beyond me at the moment!

Ah, yes again Dave! Making "smoke" would be soo much fun!

I have made some attempts at provision for any future developments by ensuring that the blast pipe is clear all the way through from the otherwise empty steam chest anyway!

Pete.

 

[James]

Pete would it be possible to see photos of the loco as a whole please?