clarkea1 Posted October 5, 2012 Share Posted October 5, 2012 Hi all, This is my first project in the rapid prototyping world (for models at least, have long used it for various engineering projects at work). It's a model of one of these: http://www.rmweb.co....49057_thumb.jpg The prototype 515hp diesel electric shunter was built in various batches by the Brush-Bagnall alliance - the story is that Port Talbot steelworks wanted to order more of the Alco shunters they had already obtained from America, but were prevented by Government policies at the time (how times change.....) and has to procure something from the UK. Hence these beasts! They are rather large, certainly outside normal UK mainline loading gauge. I've been fascinated by these locomotives ever since I worked at Port Talbot for a year and used to regularly see (and hear and feel) one of these rumbling past my office window. They were ordered in a number of batches, starting in 1953 with numbers 901-3, and also have received various modifications over the years. For example, a number were re-engined with Rolls-Royce DV8-T (v configuration) engines in the late 1970's, which resulted in the "lean to" style extensions to the engine casings as seen in this photo: http://farm8.staticf...27d42583c_z.jpg Also, the above photo of 903 shows it riding on the early-style bogies, whilst later batches had the style shown on 951 (below) and on the first photo http://www.flickr.co...N08/6370700667/ The model has been largely complete for a couple of years, but work kind of got in the way of finishing the details. It's been done in Solidworks, mainly as I use this at work and can (in my own time) get away with "homers". However, I've finally managed to finish it and found myself with enough cash in the bank to order one...... In the past I've experimented with variuous of the Shapeways materials, but have decided to try this in Prime Gray from iMaterialise. The quality seems far far better, and should cope with the details (fingers crosssed). The rest of the model is fairly straightforward - the bogies are a pair of Black Beetles, and the sideframes I envisage Rapid Prototyping assuming the body goes well. The bogies will attach to a brass strip subframe which will sit in a recess in the body. I have also left a large hole to stuff with lead! The cab will be flush-glazed in the hope of disguising the (necessarily due to min thickness requirements) over-thick cabsides. The roof I have left off so I can detail the interior. So now I just have to wait a few weeks for iMaterialise to do their thing...... If it works, I will modify the CAD to produce one of the re-engined locos sitting on the newer bogies. Might also try one of the Alco's, or even one of the newer "Trojan" locos which have recently been built for Port Talbot. I hope this is of interest to some. Cheers Alastair 6 Link to post Share on other sites More sharing options...
Arthur Posted October 5, 2012 Share Posted October 5, 2012 (edited) Looking good Alastair, I'll look forward to seeing how this turns out. Fascinating prototype, too. Edited October 5, 2012 by Arthur Link to post Share on other sites More sharing options...
clarkea1 Posted October 5, 2012 Author Share Posted October 5, 2012 Fascinating yes - also infuriating! When researching the locos I've come to the conclusion no two are exactly alike! Plus they're so old now the ones still working have had quite a few modifications. Trouble is I fear this is all leading me down a slippery slope towards some kind of BSC Margam-based layout...... 1 Link to post Share on other sites More sharing options...
Arthur Posted October 5, 2012 Share Posted October 5, 2012 Trouble is I fear this is all leading me down a slippery slope towards some kind of BSC Margam-based layout...... Don't fight it...... 2 Link to post Share on other sites More sharing options...
RMweb Premium cornelius Posted October 5, 2012 RMweb Premium Share Posted October 5, 2012 I've been really pleased with the results from iMaterialise's Prime Grey so far. The only drawback, as you've noted, is the minimum thickness but I'm sure this will improve given time. Test print v2 by fairlightworks, on Flickr 1 Link to post Share on other sites More sharing options...
clarkea1 Posted October 5, 2012 Author Share Posted October 5, 2012 That's very nice - how "fine" are the louvres on the bonnet sides? Link to post Share on other sites More sharing options...
RMweb Premium cornelius Posted October 6, 2012 RMweb Premium Share Posted October 6, 2012 0.35mm high and 0.1mm deep. Although they're replaced with etched panels on the final thing as I wanted the choice between louvred and solid sides. Link to post Share on other sites More sharing options...
clarkea1 Posted October 6, 2012 Author Share Posted October 6, 2012 Thanks - interesting to know I could have gone a bit finer on some of the details! Link to post Share on other sites More sharing options...
clarkea1 Posted October 20, 2012 Author Share Posted October 20, 2012 Well I've now received it!!! Overall I'm pleased, particularly with details liked the bodyside grills and panels as shown in the second picture. I do have some reservations - the model has been printed so that the "slices" of the rapid prototype are horizontal, i.e. parallel to the ground. This gives some noticeable stepping around the bonnet top. Preliminary experiments suggest this can be filed out, although access is a little difficult to some places. However, I am, all in all, pleased. I'm tempted to try a couple of layers of primer and a rub down before I worry too much about striations and imperfections in the surface. I must say I think the quality of the print is far better than Shapeways FUD, which was my other option for this model. Will post further photos when I have started the finishing process on the bodyshell. Other than that, there's plenty of detail to be added - e.g. handrails, cab details etc. Cheers Alastair 8 Link to post Share on other sites More sharing options...
RMweb Premium cornelius Posted October 21, 2012 RMweb Premium Share Posted October 21, 2012 Looks great Alistair! I haven't tried it myself but I've been told Mr Surfacer is pretty good for filling and smoothing stepping on curved surfaces. http://www.swannysmodels.com/Surfacer.html Link to post Share on other sites More sharing options...
BernardTPM Posted October 21, 2012 Share Posted October 21, 2012 I'd try Milliput fine on the stepping, shaped in situ with a smooth edge so that only the recess of the step if filled on the first application. If you have the choice re: orientation it might be worth turning the whole model 90 degrees onto it's side so the bonnet, cab and footplate sides are dead smooth. It may even help the roof area as the steps should be smaller that way. Is that possible or do iMaterialise not allow it? Interesting subject - they must have got their money's worth with these old beasts! Link to post Share on other sites More sharing options...
billbedford Posted October 21, 2012 Share Posted October 21, 2012 If you have the choice re: orientation it might be worth turning the whole model 90 degrees onto it's side so the bonnet, cab and footplate sides are dead smooth. That won't work. One side would be smooth, and shiny. The other side would have a lot of small pips on it where the piece has been supported during the build. 1 Link to post Share on other sites More sharing options...
thaddeus Posted October 21, 2012 Share Posted October 21, 2012 Looks pretty good Alastair, difficult to tell in the photo but the stepping doesnt look so bad. I think I would try masking and using filler primer on the worst areas before reaching for the epoxy fillers Link to post Share on other sites More sharing options...
clarkea1 Posted October 21, 2012 Author Share Posted October 21, 2012 Think I might try masking and high-build primer first - the steps are probably less than 5 thou so I think a combination of primer and rubbing down will do the job. Will try it first anyway! On some if it (tops of cab, hatches on top of bonnet) I have been able to get access with a needle file to smooth things off. The sides are much smoother than they look - normal primer and a quick rub down (prob with a glass fibre brush to try to preserve details) should see them acceptably smooth for painting. As a material, this seems far superior to FUD. Feels much more stable - I was worried the body would be fragile based on experience with FUD but I'm much more confident now I've actually been able to handle it. I thought long and hard about the orientation - but as Bill suggests, this was the best way round I could come up with! 1 Link to post Share on other sites More sharing options...
simao28 Posted October 22, 2012 Share Posted October 22, 2012 Hello Is that 00/4mm scale? It looks very good Link to post Share on other sites More sharing options...
Allegheny1600 Posted October 22, 2012 Share Posted October 22, 2012 Hi Alastair, WOW!!! That looks superb, really well done! If this is 00/4mm scale - I wonder if it is possible to print it out in another scale, like H0 perhaps? I only ask because I once bought something from Shapeways that was designed in 4mm and could be printed in other scales! (trust me to be awkward!). Thanks anyway, John E. Link to post Share on other sites More sharing options...
clarkea1 Posted October 23, 2012 Author Share Posted October 23, 2012 Yes it's in 4mm scale - the eventual loco will be EM gauge. It would be entirely possible to print in 3.5mm scale - if i.materialise don't have a scale function (which I haven't checked - they may well do) then my CAD software certainly does, so I could generate a new STL file at HO scale, if you're interested. Regards Alastair 1 Link to post Share on other sites More sharing options...
Dan Griffin Posted October 23, 2012 Share Posted October 23, 2012 where do you get the cad design programme from and is it expensive? Link to post Share on other sites More sharing options...
clarkea1 Posted October 23, 2012 Author Share Posted October 23, 2012 Dan, It was Solidworks, which is a professional engineering design package. It costs a few £k as far as I know - I am lucking in that we use it where I work, and nobody minds me using it for my own work "out of hours". Don't be put off however, there are a number of packages which are either free or very inexpensive, with which you can produce identical results. I use Solidworks as I spent many hours teaching myself how to use it a few years back and, as such, I now find designing in it very straightforward. There is a thread in this Rapid Prototyping area (I believe it's a sticky at the top of the page) which discusses the various free/inexpensive software packages. I'd hesitate to make a recommendation as I've never used any of them in anger. Best Wishes Alastair Link to post Share on other sites More sharing options...
Wild Boar Fell Posted October 23, 2012 Share Posted October 23, 2012 Yes it's in 4mm scale - the eventual loco will be EM gauge. It would be entirely possible to print in 3.5mm scale - if i.materialise don't have a scale function (which I haven't checked - they may well do) then my CAD software certainly does, so I could generate a new STL file at HO scale, if you're interested. Regards Alastair Hello Alastair, Firstly I am very impressed, the loco and CAD work look brilliant, the quality of the print also looks top notch and has given me ideas about trying prime grey!, To clarify I.materialise do have a scale function done via % on the 3D print lab section, however you may have to check your walls are still thick enough. Regards, Wild Boar Fell 2 Link to post Share on other sites More sharing options...
clarkea1 Posted October 24, 2012 Author Share Posted October 24, 2012 Hello Alastair, Firstly I am very impressed, the loco and CAD work look brilliant, the quality of the print also looks top notch and has given me ideas about trying prime grey!, To clarify I.materialise do have a scale function done via % on the 3D print lab section, however you may have to check your walls are still thick enough. Regards, Wild Boar Fell Thanks for clarifying about the scaling option. I can definitely recommend the prime grey option - it is not quite as good at Shapeways FUD, but doesn't seem to suffer from the various issues they seem to regularly have with it. I think i.Materialise are really on top of their equipment and know what they can and cannot repeatedly do with it. I think it helps that they're the "consumer" arm of an industrial RP bureaux. 1 Link to post Share on other sites More sharing options...
clarkea1 Posted February 19, 2021 Author Share Posted February 19, 2021 It's interesting to find that it was 9 years ago since I made much progress with this. Recently, the loco has gained a chassis (two Black Beetles - yes the model is going to have ample haulage capacity.....) and some progress on bodyshell finishing - lots of fiddly grab irons etc. I've also made some progress with the long handrails that run down the side of the loco. I've going to have a concerted effort to finish the loco. I now have the bogie sideframes printed up, and some nice Stenson Models air tanks etc to represent the tanks that can be seen prominently on the real things between the bogies. Then, I just need to finish the steps, make a roof, and paint it..... So, see you in 2030 for another update? Cheers Alastair 2 Link to post Share on other sites More sharing options...
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