coachmann Posted January 13, 2013 Share Posted January 13, 2013 It occurs to me the strength of the material doesnt matter in 4mm scale and larger as it could be purely cosmetic and attached to an etched brass innerd. A wagon or van for instance could have 3D detailed sides plus items such as axleboxes/springs attached to etched inner sides and W irons and brakegear. No single material is ideal for all circmstances as was shown in the past with full etched wagons and fully cast whitemetal wagons. Link to post Share on other sites More sharing options...
Rabs Posted January 13, 2013 Author Share Posted January 13, 2013 Very true, although combining multiple methods does partially negate one of 3D printing's advantages - the time saved. One of the attractions for me is that hopefully, one day soon if I want a long coal train I can print 40 wagons and they're finished and detailed ready for paint. Link to post Share on other sites More sharing options...
coachmann Posted January 13, 2013 Share Posted January 13, 2013 I had in mind things like the bogie vans with outside framing such as the ones built by the LMS on old MR and LNWR coach underframes, which at the present require the building up of multiple etchings. Anyway, I wish you every success and look forward to further developments. Link to post Share on other sites More sharing options...
richbrummitt Posted January 13, 2013 Share Posted January 13, 2013 Rabs, Thank you for your dedication to the model. I could fill the roof but I guess you are still learning a huge amount from iterating the same model. The model was quite thin in places, sorry. The rivets will come out rounded. They are drawn as short cylinders but this is something that the process as it is at the moment allows you to be intentially lazy with in the CAD (and it reduces regeneration time not having radius end edges on everything). Coachmann, This particular vehicle was chosen as a first shot for me to use this process because of the complexity of the sides. The details and the number of layers required (I estimated 4) would make an etch laborious to laminate and the completed model would also be quite heavy. Originally I built the underframe up from etched parts and other metal sections to create something with fidelity and strength that I wouldn't get from this process however the future versions (these are to 1:148 scale) will hopefully have a one piece underframe to go with the body. Link to post Share on other sites More sharing options...
Rabs Posted January 13, 2013 Author Share Posted January 13, 2013 No problem - I've just finished my latest print of it. I printed this at half the layer thickness. The rivet detail is slightly more noticable, but some of the thin side walls didn't make it through. I'm going to take a break from printing until I can sort out the ripple though. Richard, would you mind posting a photo or two of the ones that you had done at shapeways so that I can compare the results? Thanks Link to post Share on other sites More sharing options...
richbrummitt Posted January 13, 2013 Share Posted January 13, 2013 No problem - I've just finished my latest print of it. I printed this at half the layer thickness. The rivet detail is slightly more noticable, but some of the thin side walls didn't make it through. I'm going to take a break from printing until I can sort out the ripple though. Richard, would you mind posting a photo or two of the ones that you had done at shapeways so that I can compare the results? Thanks They're in a topic in this section titled 'throw a six to start' Link to post Share on other sites More sharing options...
Rabs Posted January 14, 2013 Author Share Posted January 14, 2013 Ah, found it, thanks (http://www.rmweb.co.uk/community/index.php?/topic/45596-throw-a-six-to-start/). The results look very similar! The FUD is slightly better with the smallest rivet details, but the relief and vents on the sides are almost identical. Hopefully with a little more fine-tuning I can equal FUD. I just need to eliminate that ripple... Link to post Share on other sites More sharing options...
richbrummitt Posted January 14, 2013 Share Posted January 14, 2013 Thanks. I was on my phone in the kitchen last night whilst cooking dinner so it was difficult to find and link up. Link to post Share on other sites More sharing options...
Nimbus Posted January 15, 2013 Share Posted January 15, 2013 Getting there! My ultimate test piece would be a 4mm scale domed roller bearing axlebox with legible 'SKF' lettering. In the meantime, dimensional stability over time is an unanswered question. Might be tolerable in isolation, but if part of a composite resin/etched model, would prove embarrassing. Could you perhaps measure your Tower now and come back to it in a few months? Cheers, The Nim Link to post Share on other sites More sharing options...
Rabs Posted January 15, 2013 Author Share Posted January 15, 2013 Good idea, it's 47.05mm from the top flat to the highest point on the lower arches (this is the most convenient point to measure it). It's currently sitting upright in my office at a temperature between 18 and 25C. Had a good result on the ripple last night - I think that I've almost fully eliminated it. Photos coming soon. Link to post Share on other sites More sharing options...
Marbelup Posted January 16, 2013 Share Posted January 16, 2013 Hi Rabs I only just realised you had printed my diesel loco front. I found some good pictures of the prototype today taken soon after they were delivered in 1968, including http://www.westonlangford.com/images/photo/109257/ and http://www.flickr.com/photos/railwayofaustralia/5429930775/ The real locos were made in Australia but the main equipment is from English Electric. Photos of my complete loco body printed in i.Materialise Prime Gray are at http://wasnmodeller.blogspot.com/2013/01/wagr-r-class-diesel-using-3d-printing.html Very interesting that you have had a "ripple" problem, similar to the first prints I had done by Shapeways in FUD, which you attribute to the leadscrew. I reached the same conclusion with my Shapeways print, as the pitch of the ripple was 1.27 mm or 1/20", suggesting a leadscrew with 20 threads per inch. I suggested Shapeways investigate the leadscrew theory, but they never acknowledged that as a possible cause, and didn't seem terribly interested in fixing the problem at all. I wish you success in fine tuning the mechanism to eradicate the ripple problem. I noticed you had printed one of your test models at an angle, presumably to fit within the build envelope. I have thought, but not yet tried, the idea of designing in some sort of interlocking feature to facilitate construction of a large model from pieces sized to fit the build envelope. It might even be possible to incorporate a dovetail or similar so that the joint would be mechanically strong and only need a touch of superglue to lock it in place. Link to post Share on other sites More sharing options...
Ian Smith Posted January 17, 2013 Share Posted January 17, 2013 I had in mind things like the bogie vans with outside framing such as the ones built by the LMS on old MR and LNWR coach underframes, which at the present require the building up of multiple etchings. Anyway, I wish you every success and look forward to further developments. I have had 2mmFS Outside Framed Vans printed by Shapeways in FUD (see thread http://www.rmweb.co.uk/community/index.php?/topic/55935-gwr-outside-framed-wagons/ - finished models can be seen in post 12 onwards). Ian Link to post Share on other sites More sharing options...
Etched Pixels Posted January 18, 2013 Share Posted January 18, 2013 Only real problem I've found with outside framing and 3D printing with FUD is the framing needs support material so you get a rougher surface as a result. It's certainly acceptable for things like wooden stock IMHO and I've done NLR coaches this way. Mostly I've been doing the reverse of what you suggested - I'm using a WSF core for all the complex shape/structural stuff of a coach and wrapping it with etched sides/end overlays to get the quality and detail. That avoids all the origami and soldering for a lot of shapes. Alan Link to post Share on other sites More sharing options...
lyneux Posted June 20, 2013 Share Posted June 20, 2013 Hi Rabs, How are you getting on with the B9Creator? Have you eliminated the ripple? There appears to be a new material shortly available called "Cherry" that seems very promising: http://b9creator.com/support/?mingleforumaction=viewtopic&t=553.1 I have PM'd you about getting a test print done of some of the models that I've had done in FUD. Guy Link to post Share on other sites More sharing options...
lyneux Posted June 20, 2013 Share Posted June 20, 2013 Reading more on their website it looks like the latest hardware upgrades (v1.1?) solve the banding problem. Link to post Share on other sites More sharing options...
trisonic Posted June 20, 2013 Share Posted June 20, 2013 I'll think i'll wait for several generations/years..... Best, Pete. Link to post Share on other sites More sharing options...
Etched Pixels Posted June 20, 2013 Share Posted June 20, 2013 Right now several generations is probably not very long ... Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted June 20, 2013 RMweb Gold Share Posted June 20, 2013 I'll think i'll wait for several generations/years..... Best, Pete. So that's where all the Luddites went! Mike. Link to post Share on other sites More sharing options...
Rabs Posted June 20, 2013 Author Share Posted June 20, 2013 Hi Rabs, How are you getting on with the B9Creator? Have you eliminated the ripple? There appears to be a new material shortly available called "Cherry" that seems very promising: http://b9creator.com/support/?mingleforumaction=viewtopic&t=553.1 I have PM'd you about getting a test print done of some of the models that I've had done in FUD. Guy Hi Guy, Sorry for not replying to your PM - I got it while on holiday and it slipped my mind when I got back. I'm not usually that rude! It's been slow going for the last couple of months. I've been struggling with various niggles with the printer (to be expected with a 1st generation build). The ripple was one of these and I've now fixed that to my satisfaction. Generally I'm very happy with the performance, I'm just not getting as much time to play with it as I would like. My latest results equal FUD as far as I can see, and I've had some success in painting the results. I'll put some photos up when I have a moment. I'm looking forward to the new resin, which should be a big step forward in detail. Printing has taken a back seat while I play with laser cutting for baseboard modules (see here:http://www.rmweb.co.uk/community/index.php?/topic/72424-bath-spa/). I'm now waiting for some parts for that, so I may get printing again in the meantime. More generally my modelling time is very limited at the moment, as I'm in my last few weeks of normal employment before I leave to start my own business. Link to post Share on other sites More sharing options...
lyneux Posted June 20, 2013 Share Posted June 20, 2013 Look forward to seeing you photos when you have a chance to post them! Link to post Share on other sites More sharing options...
Pugsley Posted June 20, 2013 Share Posted June 20, 2013 I'm looking forward to the new resin, which should be a big step forward in detail. If you've got some B9 Red, you can change it into the cherry, by a adding black pigment to a certain ratio (the ratio is on the B9 forum somewhere). Good luck with the new business! Link to post Share on other sites More sharing options...
Rabs Posted June 30, 2013 Author Share Posted June 30, 2013 Slightly delayed, but as promised some pictures of my more recent printing. First is the Beetle wagon without banding with and without paint. Please excuse the poor condition of these - I used them to practice my painting but didn't bother to varnish them so the paint has been knocked about a bit in a box. I then managed to drop them on the carpet where they picked up quite a lot of dirt and hair (note to self - must get wife to vacuum more often or get rid of the cats! ) And here are some microscope closeup images of some of the details. At 50x magnification these are very cruel to the model. As you can see, the detail is quite rounded and this comes from overexposure of the resin. I believe that a new resin formulation which is about to be launched will improve this. Unfortunately I can't just reduce the exposure because if I do I get holes in the model in other places. So, not likely to win any awards yet but acceptable. It isn't clear from the photos but the rivet detail on the strapping has come out, which at just 200microns in diameter I wasn't expecting! A bit of optimisation is needed to improve the 'crispness' of the details. It does depend on what you want though - these models already far surpass what is typical in white metal and they are getting close to modern injection moulded models. Here is another microscope image, along with some images of typical, modern RTR plastic models for comparison (at the same magnification). What is interesting is that they don't mould features any smaller than I am printing, they are just a bit more sharply defined. This is good because it means that the resolution (pixel size of the projector in the printer) is not likely to be a limiting factor and the 'crispness' can be improved with changes to the resin formulation and exposure times. I'm of opinion that when I get to the point that I need the microscope to see the differenced then it's good enough! But we're not quite there yet. I've also been using the printer to make parts for structures on my layout. My first one is Skew Bridge in Bath (layout topic with photos of the prototype here: http://www.rmweb.co.uk/community/index.php?/topic/72424-bath-spa/ the bridge is first mentioned on the 3rd page) These are a few of the printed parts: These parts, with their larger details, I am very happy with. I will need to slightly thicken and reprint the braces between the round pillars but that's no problem. Link to post Share on other sites More sharing options...
lyneux Posted June 30, 2013 Share Posted June 30, 2013 Very encouraging photos, thanks for taking the time to upload them! Agreed that there is room for improvement on the crispness of some of the detail. It'll be interesting to see what the new cherry material can do to help here. Guy Link to post Share on other sites More sharing options...
Nimbus Posted July 1, 2013 Share Posted July 1, 2013 I asked: Could you perhaps measure your Tower now and come back to it in a few months? Good idea, it's 47.05mm from the top flat to the highest point on the lower arches (this is the most convenient point to measure it). It's currently sitting upright in my office at a temperature between 18 and 25C. Had a good result on the ripple last night - I think that I've almost fully eliminated it. Photos coming soon. Well I reckon now's about a few months. What shape is your Eiffel Tower now? The Nim. Link to post Share on other sites More sharing options...
richbrummitt Posted July 1, 2013 Share Posted July 1, 2013 Nice results on the cattle box, even in the cruel pictures. In some respects it looks better than the shapeways models I have. I'll have to take and post some similar pictures for comparison. Link to post Share on other sites More sharing options...
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