G3 0-4-4T 'Project' based

Discussion in 'G3' started by jamiepage, 6 September 2016.

  1. jamiepage

    jamiepage Western Thunderer

    The steamchest cover on top needed finishing off with steam inlet and blastpipe. The smokebox was temporarily slid back into place and the blastpipe position marked through, the resulting position actually necessitating a pad be silver soldered in place to act as a decent seat.
    This was subsequently machined, drilled and tapped at 6 deg to the cover itself, so the blastpipe points vertically once in position on the loco.
    The blastpipe top was threaded ready for some trial and error to find the best nozzle size later.

    IMG_0008.JPG

    Once that was done, it could all be connected up and tried on air. In fact, the photo above shows the valve in motion, so it did work. (Phew!).

    Here's another view, to record the fact the wheels are going round.
    IMG_0009.JPG

    As can be seen, the knuckle joint is just temporarily held in place with a brass rivet to make it easier to fiddle around with the valve timing, but it does run so with luck it shouldn't be too hard to find a reasonable setting. Straight out of the box, it runs better in reverse; once a decent compromise has been found, it can be taken down again, and the cylinder assembly completed with gaskets or sealant etc.
    IMG_0008.JPG
     
  2. Tim Watson

    Tim Watson Western Thunderer

    Proper job! Why did you go for a single cylinder - as per the G1 project loco?

    Tim
     
  3. jamiepage

    jamiepage Western Thunderer

    Thank you, Tim.

    Yes, a project based on the 'Project', pure and simple.
    Other models have (and will have) two cylinders, but I'm happy with this one this as a simple, straightforward build.
    It was also supposed to be a quickie, with bought in wheels etc, but that altogether too ambitious target has stumbled over the hurdles of distraction.

    Anyway, it has been timed, runs nicely now in both directions, and has been stripped down prior to painting the frames, fitting gaskets and re- assembling.

    Cab, tanks, footplating etc are also ready for painting and there's no practical reason why that can't also be done now. They will only be screwed back into place as purely decorative embellishments after the boiler and steam plumbings are all fitted and proved.

    Jamie
     
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  4. Tim Watson

    Tim Watson Western Thunderer

    My P2 was supposed to be a quickie....

    Tim
     
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  5. jamiepage

    jamiepage Western Thunderer

    Another small step forward today.
    The spirit sump/burners assembly has been made.
    IMG_0008.JPG

    Sorry it's a bit monochrome.
    It is a silver soldered assembly, using a piece of 3/4in OD copper as a sump to the right, a 1/4in feed pipe and two wick holders from 1/2in.
    Cross holes and blanking ends were drilled or fitted as appropriate.

    The sump has a flange (scalloped to avoid a frame stretcher) which allows the assembly to be bolted underneath the rear bunker.

    IMG_0008.JPG

    Should it be required, bunker plus sump, burners etc should unbolt in one piece from the loco even with boiler in situ.

    IMG_0008.JPG

    The assembly has some support where it passes through the bogie pivot stretcher and shouldn't need any other support. I might, though, fit something at the front end and ensure it would be accessible from underneath so the boiler need not be removed first.

    The spirit tank sits within the bunker. Underneath, it has a delivery pipe from a spirit cock and a chamfered air pipe for chicken feed control. Both slot down through holes in the bunker base and sit within the sump.

    IMG_0008.JPG

    And finally, one day, the cab structure complete with integral coal load, will sit on top to camouflage the necessaries.

    IMG_0009.JPG
     
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  6. jamiepage

    jamiepage Western Thunderer

    Actually, there was one further step forward.
    The brake gear was built up as a bolt on piece.
    IMG_0010.JPG

    Lots of bits needed to be laminated to make each block and hanger, then each was screwed into their respective locations on the mainframes.
    With the driving wheels in place and with some plasticard to keep blocks away from wheel treads, turned cross pieces and flat pull rods were fettled and soldered to form a single assembly.

    The piece will be secured at the top of each hanger with a 10ba bolt, and with 1/32 pins at the rear cross shaft.
    IMG_0008.JPG

    Some jiggling was needed at the rear to bring the pull rods out from behind wheels with their underscale back to back, to mate with full width cross shaft.
    Fortunately the joggles sit very close to rear wheel flanges which distracts attention fairly well.
    Actually, the prototype pull rods did appear to have some kind of bodge going on there , certainly in later pre- grouping days when the loco sported the MSWJR scroll.
    The photos show 'new' fork ends bolted on with one fork sitting outside the cross shaft cranks.
     
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  7. David Taylor

    David Taylor Western Thunderer

    Glad to see some progress on this one! Looking great.

    Now you've got this far it's a good time to tell you I read an interesting article on making the crank 'axle' not a real axle but just a shaft inside the frames which is geared 2:1 to the driven axle. This gives 4 chuffs per wheel revolution and probably results in smoother running. Probably a JvR idea.
     
  8. jamiepage

    jamiepage Western Thunderer

    Hah. Now you tell me...
    I did see that idea (somewhere in the G1 mag?) a few years ago and put it in the 'good idea' box.
    The idea with this one is really to keep it as mechanically simple as possible, so really as close as possible to the original Project. Minimum parts, no water pump etc.
    All part of a cunning plan to have it finished and running months ago.
    Jamie
     
  9. Jon Nazareth

    Jon Nazareth Western Thunderer

    Jamie
    I do like the way that you have made up the brake rig, everything you make is always so 'neat'. I may try something like that on the tender for my Stirling Single.

    Jon
     
  10. jamiepage

    jamiepage Western Thunderer

    Jon,
    That is very kind of you, thank you.
    Just by chance, I stumbled across a photo of a Stirling Single model just yesterday. It seemed to be rather good; investigating further, it turned out to be VERY good. Then I saw it was 2mm (honestly, I didn't see that coming), then that it was by Tim Watson.
    Fantastic inspiration.
    Jamie
     
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  11. Mike W

    Mike W Western Thunderer

    There is also a Stirling Single in the Powerhouse Museum in Sydney. In this case by J.S.Beeson and Gauge 3. Best not look at this as it may make you give up modelling altogether!
    Beeson locomotive model of GNR Stirling 8-footer
    I have never seen another Gauge 3 model by Beeson but when he started modelling professionally it was one of the most popular scales so I am sure there must be others. Anyone know?
    Mike
     
  12. jamiepage

    jamiepage Western Thunderer

    Thanks Mike. What a superb model; I had no idea Beeson had made a G3 model..
     
  13. Jon Nazareth

    Jon Nazareth Western Thunderer

    Mike
    Mine will never look like that no matter how many months of Sundays go by. Lovely model and I wonder how long it took him to build.

    Jon
     
  14. Spitfire2865

    Spitfire2865 Western Thunderer

    Somehow my workplace network has decided this page contains material that would fall under the "sex" filter.
    Oddly only this page (6), not any of the previous.
     
  15. jamiepage

    jamiepage Western Thunderer

    Crikey!

    Tim Watson's quickie perhaps?...