TFW’s workshop

Discussion in '2mm Lounge' started by Tim Watson, 11 November 2017.

  1. Tim Watson

    Tim Watson Western Thunderer

    Here you go Ken. It converted to the GN version very early on.

    [​IMG]

    It’s probably done about 130 miles by now.

    Tim
     
  2. Martin Long

    Martin Long Member

    Tim

    In awe of your talent and ability. What a fantastic model this is and truly a worthy loco for CF.

    I make lamp irons the way you do but mine in 7mm look clumsy by comparison!

    Martin
     
  3. Threadmark: LP Running on Jerry Clifford’s test track at St Evenage CMRA show
    Tim Watson

    Tim Watson Western Thunderer

    Found some castings for the tender axle boxes at the show which with a bit of work, at work, will save me quite a bit of time.



    Tim
     
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  4. simond

    simond Western Thunderer

    Tim,

    When it went past the tweezers, that were near-on the same size... well, just fantastic.

    I must try harder. I must try harder...

    Best
    Simon
     
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  5. farnetti

    farnetti Western Thunderer

    Lot's of different coloured materials here. I seem to remember you using various heavy metals to get weight into the loco.

    Ken
     
  6. Tim Watson

    Tim Watson Western Thunderer

    There aren’t any exotic heavy metals in this engine, Ken. It’s big enough to be heavy without trying. The boiler / firebox is made from solid gunmetal, brass and nickel silver, with the motor-gearbox occupying very little space, as it is low down between the frames, as can be seen in these early photos.

    [​IMG]

    [​IMG]

    The cab is cast in ‘student’s alloy’ - brass - from plastic patterns, whilst the front end is white metal from an A4 casting (only the good will left of that though).

    [​IMG]

    The whistle will be turned from gold, so that will add a bit of weight! I’ll put her on the scales at work and report back. LP is capable of pulling anything we want to put on the back.

    Tim
     
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  7. Peter

    Peter Western Thunderer

    Hi Tim,

    Many thanks for sharing photos of your work. I have been admiring your models since the article in Model Railways (??) about the MR Spinner.

    In my humble opinion, you set an impressive benchmark, not only for 1:152.4 scale but for larger scales as well.

    The motor set up in Lord President is also impressive. Can you supply details of the motor and the attached gear-head please?

    Many thanks and best regards,

    Peter
     
  8. Tim Watson

    Tim Watson Western Thunderer

    Thank you for the comments Peter. You realise that Spinner was made 40 years ago?

    The motor-gear head is an 8x16 motor and a 1:4 gearbox made by Maxon. They are rather expensive with the Swiss franc and pound at their relative values, but as I usually take so long to make a model, the investment is spread over glacial periods of time. It is coupled to a modified low ratio transfer gearbox that I got from C&L, giving an 80:1 overall reduction. The brass flywheel might also be useful, although there wasn’t much room for it: tungsten might have been a better choice.

    [​IMG]

    The slow running Maxon motors (often with gear heads) have become standard on Copenhagen Fields, where we need massive reliability.

    Tim
     
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  9. Peter

    Peter Western Thunderer

    Hi Tim,

    Many thanks for your reply.

    It is greatly appreciated.

    Peter
     
  10. Tim Watson

    Tim Watson Western Thunderer

    Heavy weight haulage:
    Engine 140g; tender 30g.

    Tim
     
  11. Threadmark: More off the list
    Tim Watson

    Tim Watson Western Thunderer

    Just finished detailing the tender front for LP. It is very unlikely to be visible, especially with the tarpaulin over the top. Still, God and I will know it’s there.

    [​IMG]

    Tim
     
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  12. Threadmark: Going for the big stuff
    Tim Watson

    Tim Watson Western Thunderer

    A successful evening making two massive components for LP: the atomiser valve for the cylinder oil feed and a couple of wick feed oilers.

    [​IMG]

    The atomiser was made from some fine brass tube for the unions either end of the body, which was represented by a piece of nickel silver strip wrapped around it and also acted as a peg into the boiler cladding. The globe valve handle was represented by some phosphor bronze wire, which passed through the tube to also make the pipe feed. The twist drill is 0.3mm; used to make the locating hole in the cladding.

    [​IMG]

    [​IMG]

    The wick feed oilers are quite conspicuous. The sand box covers may be represented by some transfer film at the painting stage: difficult to represent them to scale, otherwise.

    [​IMG]

    The oil reservoirs were represented by a bit of brass bar filed in the middle to visually separate the two oilers.

    [​IMG]

    Tim
     
  13. Tim Watson

    Tim Watson Western Thunderer

    Lord President’s tender is now complete, except the brakes. The pull rods were made from quite thick nickel silver sheet, filed down to represent the bearings for the cross members that tie both sides together in between the wheels. These rods are quite substantial and conspicuous on the real thing, but often modelled over scale. The rods for LP also incorporated three rebated lips across their top edge to solder to the tender frames: they are otherwise quite vulnerable to handling.

    [​IMG]

    Rear view shows the vacuum and heating pipes also in place.

    [​IMG]

    Side and 3/4 view (bit cruel) shows the fork joint represented for the front hanger of the brakes pull rod and the cross arm pivot representation. They would look a bit bland otherwise.

    [​IMG]

    [​IMG]

    Not sure whether to model the tender brakes. They are well hidden behind the frames, so will probably only act as fluff catchers. However, the engine now needs the brake blocks making: I’ll probably turn these with a large flange that can be filed to make the hangers. The brake pivots were fitted to the chassis long ago.

    Tim
     
    Last edited: 27 January 2018
  14. jamiepage

    jamiepage Western Thunderer

    Got to say, especially coming from the other end of the scale/ size modelling spectrum, I am finding this thread utterly absorbing. Thanks very much.

    And good for WT- what a great variety of modelling inspiration.
     
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  15. Threadmark: Sort of brakes
    Tim Watson

    Tim Watson Western Thunderer

    Realised after looking long and hard that I hadn’t put in the rear two brake hangers. These make a big difference to the appearance and, frankly, take away from the need for the brake shoes themselves, which are tucked up well behind the frames. Ironically, the brakes themselves, being attached to the body, are not part of the internal chassis and so the advantages of split frame pick up don’t work here.

    [​IMG]

    Exhibition maintenance on our locos on CF is a constant battle against fluff, not always helped by brake shoes. The engines can attract enough of the stuff over a weekend to set a Hotpoint tumble drier on fire.

    Tim
     
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  16. Tim Watson

    Tim Watson Western Thunderer

    The cylinder drain cocks and pipes are very obvious on a P2, launching themselves forwards to join up eventually with the front guard irons, as was also the case on the A4s, as built. Quite sensibly, they were shortened in BR days. On LP they were made from a length of 0.25 phosphor bronze wire folded back on itself and silver soldered together (with silver solder paste) over about 15mm length. This produces a nice strong length of double ‘pipe’ that is also resistant to soft soldering temperatures.

    [​IMG]

    These were then bent up to shape to enter the drain cocks themselves, which were made from small brass tubing that was a plug fit into holes already drilled in the bottom of the cylinder casings. The control link was a short length of nickel silver strip, bent at ninety degrees at the front to represent the rest of the linkage. The pipes really do swing right out at the front to clear the pony truck on tight curves.

    [​IMG]

    The pipes were soft soldered onto the front guard irons and a little bit of epoxy used to secure them into the cylinder: I wasn’t going to waft a soldering iron near that lot at this last stage. At the same time, the bearing cover for the front brake cross shaft was fitted in the chassis, behind the cylinders.

    [​IMG]

    Now for the RHS. The bits are made, but it will have to wait while the epoxy sets. These pipes really help to join up the font end of the engine; without them, it looks a bit like Jimmy Edwards without a moustache (only a few on the forum will remember him).

    Tim
     
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  17. Tim Watson

    Tim Watson Western Thunderer

    Finished off the other set of drain pipes this evening. The two photos show the clearance between the pipes and pony wheels. Should be OK, unless the engine damages the pipes in some minor misdemeanour: as often happens with miniature live steamers.

    [​IMG]
    [​IMG]

    Shorting out isn’t a problem, of course, because of split frame pick up. The insulating PCB between the cylinders and the outer cover/valence is pretty obvious in these views.

    Tim
     
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  18. Tim Watson

    Tim Watson Western Thunderer

    Finally started on the engine brake gear for Lord President
    A pattern in styrene was made to fit on the brake hanger pivots to check the size.
    [​IMG]

    This then needed to be copied eight times in 20 thou nickel silver. To make eight pieces, a strip was tinned, folded up, and then squeezed together in the vice and re-heated to join up the layers.
    [​IMG]

    This block was then drilled with two 0.5mm holes for the hanger and push-pull beam pivots.
    [​IMG]

    This was then filed up in the vice.
    [​IMG]

    And then a lot more filing.
    [​IMG]

    Next stage was to separate them and file in the brake shoes and hangers. Final filing and shaping of the brake blocks and hangers required the use of some nice safe-edged Vallorbe escapement files.
    [​IMG]
    What can’t be seen is the finger nail that would be holding down the brake block.

    Each block was made to fit a particular pivot, as my chassis drilling wasn’t that accurate.
    [​IMG]

    They tuck snugly into place on the wheels and definitely fill the space well, helping to hide the overscale flanges. There is no way I could have made this engine with scale size wheels: the brake gear would have been impossible to fit.
    [​IMG]

    The brake cross beam assemblies consist of thin double sided PCB with a brass pin soldered across and gapped. The assembly is gently sprung over the brake hanger pivots: these are a shouldered 16BA steel bolt tapped through the frames.
    [​IMG]
    [​IMG]

    The cross beam was also strengthened by a piece of shim brass on the other side to span the weakened area of the insulation gap: this will have the push/pull rods soldered to it to allow the brakes to be held in the ‘off’ position.
    [​IMG]

    Before mounting on the engine the whole lot was chemically blacked.
    [​IMG]

    Afraid these photos are desperately cruel. Just need three more and the push pull rods.

    Tim
     
    Last edited: 9 February 2018
  19. Threadmark: Brake gear rigged
    Tim Watson

    Tim Watson Western Thunderer

    At last the brake gear is complete and rigged (representative, rather than accurate).
    [​IMG]

    The close up shows it filling in the bottom half of the chassis
    [​IMG]

    It scarcely shows in the general view, as it is currently too black.
    [​IMG]

    Lord President is almost complete on the LHS. There is a gubbins on the front of the Cartazzi frame extensions that ought to be modelled, but I don’t have a decent image or drawing of it. And of course the whistle and safety valves: a nice little turning job in non-tarnishing alloy.

    Would be nice to get some good photos of LP before painting.

    Tim
     
  20. David Varley

    David Varley Western Thunderer

    What's the build time so far, Tim?