Adams T3
- Thread starter Thirtysecond
- Start date
Thirtysecond
Western Thunderer
The female part is firmly mounted under the loco cab floor. The male part once attached to the female part is free to move sideways is it mounted through a slot milled in the mounting bracket (see photo three posts above which shows both male and female units)
Thirtysecond
Western Thunderer
Prototype tender now effectively finished. Finally installed
the electronics. Pressure gauge and water level LEDs are on the tender as are the battery, electronics and on/off switch.
There are three leads (high , low and common) which will be connected to the loco via micro connector (aircraft R/C type) . It all tested out with red for "top up NOW" and green for " you'll be priming soon!"
the electronics. Pressure gauge and water level LEDs are on the tender as are the battery, electronics and on/off switch.
There are three leads (high , low and common) which will be connected to the loco via micro connector (aircraft R/C type) . It all tested out with red for "top up NOW" and green for " you'll be priming soon!"
bambuko
Western Thunderer
Thank you for that.
It was "silicon sleeves" in your description that had me puzzled, but thanks to this photo:
it is all clear now (I can see the sleeves and can see how they work) - thank you.
Thirtysecond
Western Thunderer
Boiler and smokebox prototype complete. Note that the tiny smokebox is packed with connectors. Its a multi-flue boiler fired by Meths or coal.
adrian
Flying Squad
Very nice, clean and compact - the copper tube bending is exemplary. Unfortunately it raises a few questions - sorry.
So it appears that although a couple of tubes are filled with superheater elements it seems that a couple seemed to be blanked off with brass plates and some have blanks bolted in with a ptfe washers - what is the purpose of these? Many thanks.
Thirtysecond
Western Thunderer
Here is a different loco using the same principle where it is perhaps a little clearer. What you saw as blanks are actually o-ring based connectors. The ones withe PTFE washers are probes for the electronic water gauge.
All bushes are at the FRONT of the boiler because at the back is a scale backhead with no room for bushes. An added bonus is that with all steam and electrical connections going through a manifold on the smokebox floor, releasing a couple of screws on that manifold enables the complete boiler/smokebox assembly to be removed in a couple of minutes.
David Halfpenny
Western Thunderer
Brilliant, Derek!
While I'm assuming you're spirit-firing from the firebox, this design has potential for improving gas firing.
From time to time I've toyed with the idea of a recuperative radiant cartridge burner.
While I'm assuming you're spirit-firing from the firebox, this design has potential for improving gas firing.
From time to time I've toyed with the idea of a recuperative radiant cartridge burner.
i.e. a radiant poker burner in which the flue gas passes down the middle of the burner on its way to the smokebox, giving up more of its heat to preheat the fuel and combustion air.
Until now, I'd always seen it as a snag that all the connections (fuel, air-in air-out) were at the smokebox end, but now . . .
David
Thirtysecond
Western Thunderer
The pipe looms have now been installed in the prototype. They took some fitting in in such a small loco as they have to avoid the firebox, various eccentrics, and all the different valves mounted in the frames. You can clearly see the manifold whose other half is the base of the smokebox. The counterbored holes take the o-rings.
The lubricator pipe, axle pump eccentric and ram have yet to be added .
The lubricator pipe, axle pump eccentric and ram have yet to be added .
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Thirtysecond
Western Thunderer
Alternative firing now complete. Ashpan not shown but done!
Reverser and cylinder drains all in place. Blower and by-pass controlled by, what are on each seat on the original, injector water valves.
Reverser and cylinder drains all in place. Blower and by-pass controlled by, what are on each seat on the original, injector water valves.
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Thirtysecond
Western Thunderer
Thanks mswjr. The problem with this prototype at every turn is space. Its essentially, by later locomotive standards, a very small loco, so getting everything we want into such a small space requires a lot of discussion, trial and error, and design iteration. We were going to add an inertia unit *(slo-mo) but there just isn't room. That will have to wait for the next model!!!!
Thirtysecond
Western Thunderer
A bit more progress on the prototype. With cab, cab roof and multiple splashers its starting to look the part.
Here's a problem we should have thought of. Coal firing requires a slightly oversize firehole. That has serious knock-ons for our scale backhead. Essentially all the other fittings on the backhead get squashed together more than they should be. Oh well, cross that bridge when we come to it.
Over this weekend I shall be putting the operating levers on the sliding firehole doors and adding the firehole tray, all of which will overlay the backhead you see in these pictures. Everything on this has to be silver soldered because of the working temperature.
Strangely, on the original, the left hand operating lever is on the INSIDE of the door. Never seen it before on any other loco and must have been an awful environment for a sliding joint (searing heat, dust and dirt). Artistic licence, I think ours will be on the outside. Makes more sense.
Here's a problem we should have thought of. Coal firing requires a slightly oversize firehole. That has serious knock-ons for our scale backhead. Essentially all the other fittings on the backhead get squashed together more than they should be. Oh well, cross that bridge when we come to it.
Over this weekend I shall be putting the operating levers on the sliding firehole doors and adding the firehole tray, all of which will overlay the backhead you see in these pictures. Everything on this has to be silver soldered because of the working temperature.
Strangely, on the original, the left hand operating lever is on the INSIDE of the door. Never seen it before on any other loco and must have been an awful environment for a sliding joint (searing heat, dust and dirt). Artistic licence, I think ours will be on the outside. Makes more sense.
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Thirtysecond
Western Thunderer
Firehole doors completed. A more tricky task than you would think. The variables are the length of the linkage and the position of the pivot points. When shut the doors have to meet exactly in the middle and then they should open an equal distance exposing the firehole completely. Pure geometry is not sufficient however as every joint has an amount of "play"which is additive.
The only solution I have found is to experiment using temporary Brass linkages with multiple holes drilled then, once the correct holes/layout has been achieved, transfer those measurements into Steel.
The main lever is bent to allow for the oilcan/teacan tray and the vacuum brake pipe which goes vertically down the right hand side of the backhead.
The temporary Brass linkages:
The only solution I have found is to experiment using temporary Brass linkages with multiple holes drilled then, once the correct holes/layout has been achieved, transfer those measurements into Steel.
The main lever is bent to allow for the oilcan/teacan tray and the vacuum brake pipe which goes vertically down the right hand side of the backhead.
The temporary Brass linkages:
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michael mott
Western Thunderer
Beautiful work, I am really enjoying seeing how this piece of model engineering is developing.
Michael
Michael
Tim Watson
Western Thunderer
The problem with those elegant sliding doors is that they ‘coke up’ and need their backs scraping quite frequently (at least they do on my 4” scale road locomotive).
Tim
Tim
Thirtysecond
Western Thunderer
I am in total awe of people who can fabricate intricate, tiny patterns for casting. Chris Tolhurst is a master. It's jewellery making really. Here are two patterns he's just produced for the T3; the steam brake and the combined train brake.
I am currently assembling the backhead for the prototype and will use the patterns in lieu of castings for the purposes of getting everything positioned. Of course I'll have to bear in mind that the final castings will be slightly smaller than the patterns.
I am currently assembling the backhead for the prototype and will use the patterns in lieu of castings for the purposes of getting everything positioned. Of course I'll have to bear in mind that the final castings will be slightly smaller than the patterns.
David Halfpenny
Western Thunderer
Total Awe indeed, Derek!
Given the limited supply of Chris Tolhursts, it's good to encourage other people to have a go themselves.
He is sufficiently encouraged to start upgrading his Swiss-prototype Aster locomotives:
These are the actual lost-wax castings sent back by the foundry, and Markus says they look even better than in the photo.
If you are interested in how it's done, starting with 3D Modelling, through to LCD Resin Printing (as opposed to filament printing), you are welcome to join the quite new Gauge One 3D Circle at:
https://groups.io/g/GaugeOne3DCircle
(While the Gauge One 3D Circle is a special interest group of the Gauge One Model Railway Association, membership of G1MRA is not essential to join the forum.)
David 1/2d
Given the limited supply of Chris Tolhursts, it's good to encourage other people to have a go themselves.
Never be afraid of having a scrap box!
Jewellers now have an alternative, namely Resin Printing the individual waxes, like these first attempts by Markus Neeser in Switzerland.
He is sufficiently encouraged to start upgrading his Swiss-prototype Aster locomotives:
These are the actual lost-wax castings sent back by the foundry, and Markus says they look even better than in the photo.
If you are interested in how it's done, starting with 3D Modelling, through to LCD Resin Printing (as opposed to filament printing), you are welcome to join the quite new Gauge One 3D Circle at:
https://groups.io/g/GaugeOne3DCircle
(While the Gauge One 3D Circle is a special interest group of the Gauge One Model Railway Association, membership of G1MRA is not essential to join the forum.)
David 1/2d