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lyneux

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  1. lyneux
    I finally finished off the rake of 5 scratch-built wagons that were built by prominent modeller Andy Elliot who built a number of models for Foster Yeoman before he sadly died five years ago. I obtained these last year from Gridwatcher who was a mate of Andy's.
     
    Andy constructed the wagons in styrene sheet and they are surprisingly detailed. I've done them as a rake of 2 outer wagons and 3 inner wagons:
     

     
    There was a actually quite a lot to do in the end:
     
    - Creating mounting points for the bogies and fitting my 3D printed LTF-25 bogies
    - Fitting lead weight
    - Fitting kadees as inner couplings at prototype height
    - Adding buffers to outers from Skits
    - Fitting kadees as outer couplings at normal kadee operating height
    - Painting - lots of coats of Phoenix enamels!
    - Transfers - from Fox and using my own home-printed data panels
    - Varnishing - good old Klear
     
    They still need weathering and one or two extra details adding such as the distinctive coupling bars. Here are a couple of shots of the individual wagons:
     
    Outer wagon: 17918

     
    Inner wagon: 19890

     
    Just to show how much had to be done, here is a pic from Gridwatcher showing the state of them when I got them from him:
     

  2. lyneux
    I'm not the first person to attempt to make an JMA from the Bachmann HHA, but given that I had already done a version of the bogie for this wagon, it seemed silly not to see how quickly a couple of them could be bashed into shape. The first step was to acquire and dis-assemble a Bachmann HHA. Take all the screws out from the bottom of the wagon and twist. The wagon snaps apart into the pieces seen below:
     

     
    Next step is to chop the detail off the wagon sides:
    The grid at the end (international wagon data panel?).
    Buffers and coupling (one end only as this will be an outer).
    Brake handles and stop cocks.


     

     
    Ping off the yaw dampers and small plastic triangles attached to the side. These are just glued on so come off easily:
     

     

     
    The first tricky part: cutting a hole for the brake actuator. Locate the plate with the two semi-circular cut-outs on the solebar. Mark a square on the body 22mm from the end of this plate and 2mm up from the solebar. It should be about 3mm high and 4mm wide. I drew this on in pencil as a guide. Then drill out using a 3mm drill bit, centring the drill against the left side of the square.
     

     

     

     
    Using a square file and a round file I first opened the hole into a squarer shape and then cut towards the end of the wagon to open it out and produce the distinctive shape. I finished off the bottom right of the hole using a half round file. After this, I edged the hole with some 0.3mm brass wire (not too hard to bend to shape) and super-glued this on using sparing amounts applied with a cocktail stick. Finished result below:
     

     

     
     
    I then added a representation of the lever on the brake distributer out of 0.3mm brass wire and a small circle of electric wire sheathing. I did think about fitting a Wizard models cast distributer in this position but the unprototypically thick plastic sides already mean that the recess is very deep so I'm going to settle for a representation of the red lever (which is about all you can see in the darkness of that cavity). There is a small mounting point (or something?) near to the right end of the wagon so I've represented this with a small piece of 40 thou square strip filed down to match the profile of the wagon side.
     

     
    The end panel is totally wrong for the JMA. To correct this, I filed off all the moulded detail and filled any holes so that I had a completely flat panel. I then added 40 thou wide (10 thou thick) strip to represent the corrugations. I used a piece of 30 thou styrene to space them out and then primed the finished piece in grey ready for casting and cast it in resin as a one-part mould.
     
    Here is a view of the end panels (original on the left and modified on the right):
     

     
    Here is one of the resin copies loosely held in place (no glue yet!):
     

  3. lyneux
    I've had the latest prints back from Shapeways of my Westinghouse Brake distributer and Roevac vents and I'm slightly underwhelmed by them. I'm sure that I have had prints in the past where I have seen details that are 0.2mm in diameter which don't appear to have come out on these. Perhaps when they are cleaned and primed they will look better? This is the problem with Shapeways - massively variable results!
     
    4mm Westinghouse Brake Distributers:
     

     
    You can just about see the detail on the distributers in this photo (e.g. the star pattern on top) but screw details are lacking.
     

     
    Roe-vac vents in 4mm and 7mm:
     

     

     
    7mm Roe-vacs:
     

     
    PTA Wagon Underframe components (including Westinghouse brake distibuters) v0.3. This is one of the better prints, for some reason the brake distributers are much crisper on this print than the other model where 18 have been placed on a cube-shaped sprue:
     

     
    And for reference, here are renders of the 3D files:
     


     
    None of the screw detail on the Roevacs came out in either 4mm or 7mm even though each screw in 7mm is 0.3mm wide and 0.2mm high (within the parameters for "surface detail" in FUD and therefore should come out?
     


  4. lyneux
    The need to place an order with Shapeways for components for the PTAs has seen some frantic work in completing a few other bits that have been on the back-burner for a while. One of these is a version of the LTF-25 bogie designed for the national power JHA/JMA:
     

     
    There are actually an awful lot of differences between this bogie that is fitted to these Finnish-built wagons and the one fitted to the ARC JHAs (built in the UK). Again, there are two versions of the bogie, one with a hand wheel and one without and again each of these has differences when viewed from the left side or the right side. The picture above shows the hand wheel version.
     
    Here are the main difference between this version and the ARC version:
    The main frame has a deeper profile box section onto which the secondary air suspension sits.
    Mounting points for the dampers are totally different
    Different hand wheel mechanism and brake application indicator board positioned side-on
    Larger cable stays


     
    Like the ARC bogie, this version also makes use of Colin Craig wheels and hand wheels plus the sequin and o-rings for secondary suspension. I have cut pilot holes for Colin Craig hand wheels that are in different positions on either side of the bogie.
     
    Here is a prototype view for comparison (albeit from the other side):
     

  5. lyneux
    More progress on the LTF-25 bogie and the JHA this month.
     

     
    Back in August, I was offered the chance to acquire 5 scratch-built JHA bodies. This seemed like a good solution in order to get a mini rake of 5 wagons up and running quickly. Colin Craig kindly supplied me with a few more wheelsets at Scaleforum so I've now been able to put the first wagon together with the better pair of my test print bogies.
     
    Although the wagon bodies could do with a bit more detailing, rather than go to town on them, I've decided to simply paint, transfer and weather them until I finish my own bodies. The following shots are of the first wagon sprayed with Phoenix paint (ARC mustard & grey). I've assembled and painted enough of Colin's 4mm diameter etched handwheels to do the mini rake of 5 but I want to make sure that the paint job is correct before fitting these. I'm planning to fit Kadees to all vehicles and buffers to the outer vehicles.
     
    Finally, I tested fitting in brass bushes as bearings into one of the test printed bogies. I had to drill out the axle holes to 3mm and then inserted the bushes from the front of the bogie. They are a snug fit and the front of the wheel stops them from coming out. They are also fairly free running too. The main faff is fitting the wheels as they both need to come off the axle in order to get them in place. This is a delicate operation but by following a few basic "rules" and the aid of a back to back gauge it can be accomplished quite easily without breaking any of the fine detail.
     
     



     
    I'm not really happy with the colour of the Phoenix paints: they seem a little bit dark compared to prototype photos. I've linked to a couple of prototype photos below that I've found on the web. Gareth Bayer's shots were taken in the late 90s and the wagons have had a chance to fade and weather down a bit. However, even in the second shot (taken early 90s) the grey looks quite a bit lighter.
     
    If anyone has good side-on colour shots of these wagons from the period when they were new then I'd love to see them for a comparison.
     


  6. lyneux
    Unfortunately the latest prints of the revised design haven't come out too well: they exhibit the rippling effect that many people are seeing and Shapeways have now agreed to re-print these for me. This seems to be a common problem at the moment with frosted ultra detail from Shapeways and people are speculating that it is to do with the calibration of the machines. You can make your own mind up and read more about the problem on this thread on Shapeway's forum: http://www.shapeways.com/forum/index.php?t=rview&goto=40321#msg_4032.
     
    Despite this, I thought I'd have a go at priming the best of the rippled prints and seeing just how well the new LTF-25 design fares... is it any quicker and less fiddly to put together? Four of the prints are totally unusable, whilst the one in the pictures is the best of a bad bunch.
     

     
    I'll let the pictures tell the story, suffice to say, they go together very easily with Colin Craig's wheels and are nice and free-rolling on the Markits bearings. Plus the wheel sets are now easily removable for e.g. painting.
     
    Twist the wheel set to remove the wheel - being careful not to pop the black plastic bush out:
     

     
    Thread the Markits bearings onto the axle:
     

     
    Using a back-to-back gauge, replace the wheel:
     

     
    Drop in the wheel set from below with the bearings in the centre:
     

     
    Slide the bearings into position with a pair of tweezers:
     

  7. lyneux
    I've been working again on the 3D model and refining it to the next version ready to print:
     

     
    Refinements include:

    Revised secondary dampers (shown in blue) with extra strengthening (these broke in the first test prints). These also now have their own sprue (shown in green) to try and stop them breaking off during the printing and cleaning process. Spare dampers are also included in case of breakages.
    New mechanism for inserting the wheelsets. With two Markits brass bushes positioned flanges to the middle on the axle, the axle can be inserted from below. Bushes are then pushed outwards. The missing piece of the bearing housing has also been included so it can be glued in place after the wheels are fitted. These pieces are printed on the spacing sprue between the frames (you can't see the sprue in this view but it's there!). Again, I've included two spares in case of damage or loss.
    Extra bracing to add strength to the side sub-frames

    Note: all sprue elements shown in green and included to try and minimise warping during printing. These are easily cut off from the final print.
  8. lyneux
    The test print arrived last week and I couldn't wait to try it out with Colin's Wheels. Here it is with a white background:
     

     
     
    And here it is against black (seems to show up more detail and yes, they are the same wheels!):
     
     

     
     
    I was initially worried about the material (frosted ultra detail) not being strong enough and/or warping but it was gratifying to see that the bogies are nice and strong and totally "true". I added a bit of sprue between the ends of the frames (evident in the pictures) to keep the frames the right distance apart. I'm not sure that this is totally necessary. The amazing thing is that none of the brake gear is damaged at all (I was expecting this to be the weakest bit).
     
    The axle holes need opening out a bit with a cutting broach to make them free rolling. I've also lost a few of the dampers in the process of handling and washing them. I'm not totally convinced that metal axle on plastic will give a long life to the bogies so I've ordered some Markits bush bearings for 2mm axles. On the test prints I'll open out the bearings to 3mm with a drill to accept the bushes once they arrive.
     
    I've washed a lot of the residual wax off the bogies using warm soapy water and a soft paintbrush (inserted into all the nooks and crannies). This seems to have done the trick and it is now a case of seeing how well they take paint.
     
    Things to improve on in the next batch:
    Print with a 3mm hole ready to accept the Markits bearings (assuming they fit on the test print).
    Strengthen the join between the secondary dampers and their attachment points (make a bigger cross section so they don't snap off). I might also add a sprue that joins the 4 secondary dampers together to keep them from snapping off. Will also print some spare ones as I've lost a few on the carpet!
    Add a bit of bracing between the main and the side frames (light and dark grey bits in the 3D render on my previous blog entry). The extra bracing on the bogie with the handwheel has a significant strengthening effect.

    Off now to make up some of Colin's handwheels and to order some sequins and O-rings to act as the primary suspension units.
  9. lyneux
    I've been working on a little project lately to produce model of an ARC/Hanson JHA (build code JH016D/JH017D). Not wishing to bite off more than I can chew, I've started with the LTF-25 bogie. If I never make the wagon, I can at least make a rake of National Power JMAs by re-bogying the Bachmann HHA (+ a little work) as these use a very similar bogie.
     
    First a little background on the prototype. Each bogie is different and non-symmetrical. One is hand-braked, the other isn't and the secondary dampers point inwards at the ends of the wagon. This means 4 different views:
     




     
     
    After much faff with Blender, the 3D model was ready to print. The handbraked bogie is shown on the left and the non-handbraked on the right. You'll notice several pieces missing. I am planning to use Colin Craig's excellent handbrake wheels for the handbraked bogie and the primary dampers will be constructed using Chris Wild's rubber o-rings and sequins technique. I'm also planning to use Colin's excellent wheels for the finished bogie.
     
    The blender file:

     
     
    And once uploaded to shapeways, their rendering of the file:

     
    More to follow, including pictures of the first test print results from Shapeways...
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