billbedford Posted September 18, 2011 Share Posted September 18, 2011 Here are a few prints I received in the last couple of weeks. I shall be at Scaleforum next week-end if you would like a closer look The first is the body of a LNER Toad E, This is shown as it arrived except for a quick blow-over with primer to make it more visible. The others are the parts for a coach assembly frame. for a LNER TPO. The material is glue-able with cyano-acrylic glues and allows brass sides and ends to be finished in the falt and before assembly. Link to post Share on other sites More sharing options...
RMweb Gold griffgriff Posted September 18, 2011 RMweb Gold Share Posted September 18, 2011 WOW.... it's certainly a dynamic science this printing lark, it seems to advance all of the time . Link to post Share on other sites More sharing options...
Red Devil Posted September 18, 2011 Share Posted September 18, 2011 Shapeways or a different supplier? Both look very well, really like the TPO idea............. Link to post Share on other sites More sharing options...
Atso Posted September 18, 2011 Share Posted September 18, 2011 I've said it on another forum but these are worthy of saying it twice, excellent work! As per Red Devils post, I really like the idea for the TPO, a good way of using 3D printing while keeping costs lower. What else have you got in store for the 4mm modeller? Link to post Share on other sites More sharing options...
craigwelsh Posted September 19, 2011 Share Posted September 19, 2011 Shapeways or a different supplier? Both look very well, really like the TPO idea............. They are listed on Shapeways http://www.shapeways.com/hisdesign?user_id=11818 3D printing is certainly getting there now though you may still lose some detail trying to clean up the surface finish at the moment. Link to post Share on other sites More sharing options...
iak Posted September 19, 2011 Share Posted September 19, 2011 Interesting developments indeed. That Toad E is fascinating to behold especially. Hmmmmmmmmmm Link to post Share on other sites More sharing options...
Red Devil Posted September 19, 2011 Share Posted September 19, 2011 They are listed on Shapeways http://www.shapeways...n?user_id=11818 3D printing is certainly getting there now though you may still lose some detail trying to clean up the surface finish at the moment. Yep, so are most of mine, but I'm not using them to do much at the moment! Always on the look out for a new product or supplier................ Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 15, 2011 Share Posted November 15, 2011 I recently was sent a body for an Irish diesel locomotive so I could measure it up and fit a mechanism to it. But I was astounded to see the surface finish looked and felt like someone had sprayed it with flock! This body apparently came from Shapeways, and I am wondering if this is typical of the results they produce? If so, it would be a devil of a job to clean up that surface enought to do a decent paint job, and you would most likely lose a lot of surface detail in the process. I have been using 3D printing processes for many years now, and from a number of suppliers, but I would never use a supplier that produced a furry finish like that. I use Finelines in the US for my printing, and while is it not a cheap process, the surface does not need any cleaning afterwards. I also note that there is a temptation to produce body shells in one piece when this is not always optimum for the build direction of the printing process. In general, it is better to produce a body as a series of flat-pack sections then assemble them with glue later. Anyone have further thoughts on this? Link to post Share on other sites More sharing options...
billbedford Posted November 16, 2011 Author Share Posted November 16, 2011 Shapeways offer the output of a number of different machines. Each has its own strengths and weaknesses. The pieces you have seen were SLS (Selective Laser Sintering) using a nylon material. This will always produce a sandy textured surface. It can be brought to a good surface finish without resorting to the usual abrasive attacks. Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 16, 2011 Share Posted November 16, 2011 Yes Bill, but there would be inevitable damage to the body in doing so surely. The one I looked at was a dark grey, almost black in colour and the surface was very furry. Having received shiny, clean and highly detailed builds from Finelines, I cannot see why anyone would bother using a company or process that produces a furry result. Link to post Share on other sites More sharing options...
Pugsley Posted November 16, 2011 Share Posted November 16, 2011 I cannot see why anyone would bother using a company or process that produces a furry result. The only reason that I can think of is cost - I understand that the Finelines service is rather expensive. Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 17, 2011 Share Posted November 17, 2011 Martin, I would agree that cost is a big issue, but I suspect they will have to bring their prices down in order to compete with all the other 3D printing services that are starting up. Just today, I got a piece of SPAM from a Chinese company offering their services, and dirt cheap. Trouble was, there was nothing on their web site to say what the quality is like, as in no specs. I guess my interest is a little different from other modellers as I view the process as a way to obtain good quality patterns to use for casting kits from. Link to post Share on other sites More sharing options...
Pugsley Posted November 17, 2011 Share Posted November 17, 2011 I guess my interest is a little different from other modellers as I view the process as a way to obtain good quality patterns to use for casting kits from. Not that different, as that's exactly the way that I view the process. I guess it depends if Finelines can reduce their prices - do you know what equipment they use? Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 17, 2011 Share Posted November 17, 2011 Yes, their main machine for high resolution builds is the Viper HR, they have nine of them, but they also have the SinterstationPro and iPro for other work. I have sampled their Micro Resolution builds for a forthcoming kit, and the quality is outstanding, and the finish is a satin sheen. Link to post Share on other sites More sharing options...
Petri Sallinen Posted November 18, 2011 Share Posted November 18, 2011 Geoff, I have similar thoughts as you in many cases. We produce small series kits of Finnish prototypes in 1:87 scale. Our typical run for one kit is about 100-200 pieces and our kits consist of resin parts, etched parts and brass cast parts. Nowadays we make originals for resin castings only by 3D-programs. The company that sells us resin casting services also makes the 3D printings from our STP-files by very good quality — the surface does not need any fine-tuning. Yes, that is costly (cost for one kit body is something like 400 euros), but saves our work. We have also used in some cases rough prints that we have finished ourselves by sanding and detailing like you might have seen earlier http://www.rmweb.co....s/page__st__125 — too much work by comparison with costs of high quality printing. We also have to remember that the printing costs will spread with 100-200 kits — not so much per one kit. There also might be some problems with making molds with rough prints: the rough surfaces also inside body have to be sanded carefully and filled before making silicon mould (the silicon rubber get stuck with rough surface) so that means more job. Rough printings are not very accurate. The window openings are not in same size although they had to be. Our motor wagon kit has 12 same size window openings, but they are not exactly in same size when using rough prints. For the kit we made injection molded windows — only one aluminium mold made by milling (making one mold is cheaper than 12). After making windows we noticed that in some openings window fits well, in some openings it was too tight and in some openings loose. So the high quality printings would have been better…. This is the ready resin body with details. As I said, every windows do not fit in openings same way. Yes, in some cases it is better to make printing in parts instead of one piece. In pictures you will see our bitumen wagon. The body has been printed in six pieces: both ends, saddles and container with doom. After that the parts have been glued together, but no finishing for surfaces was needed. The body in pictures is ready made resin part. If the same company makes both printings and resin castings, they also might add some parts to drawings before printing that are needed in molding process: molding pipes etc. This is also cost effective for us. I hope that our experiences helps you with your projects. Petri Sallinen Helsinki Finland Link to post Share on other sites More sharing options...
Pugsley Posted November 18, 2011 Share Posted November 18, 2011 Thanks Petri - that's really interesting and useful information. I like the bitumen wagon, the combination of etched chassis and resin components was what I was going to do on one of the projects I'm currently working on. Out of interest, was the reason for moulding the barrel in resin, rather than using a rolled etch with resin ends and details, the raised seams on the tank? On mine I was planning to use an etched barrel, rolled to the correct diameter, with resin ends and hatches, etc. Link to post Share on other sites More sharing options...
Petri Sallinen Posted November 18, 2011 Share Posted November 18, 2011 Martin, I thank you for your intrest. The reason for moulding the whole barrel in resin was make it as simple as possible to build. Here is also some pictures of underframe, but without lost wax brass parts. These pictures might be off topic, I am sorry for that. Link to post Share on other sites More sharing options...
Pugsley Posted November 18, 2011 Share Posted November 18, 2011 These pictures might be off topic, I am sorry for that. With models like that, as far as I'm concerned you can carry on being (slightly) off topic with no apology required! Thanks for letting me know the thinking behind the resin barrel. Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 18, 2011 Share Posted November 18, 2011 My apologies for being a bit off-topic too. Those are very impressive models Petri, and a good example of the advantages of using mixed media. This is a view of the model I am currently developing as a kit. It is a Victorian Railways W Class shunter, built in Australia to an obvious German design. The design is a typical German centre cab, offset with one end shorter than the other. The kit will be in pewter (for weight) and will come as a flat-pack of sides and ends that need to be assembled. This requires 12 flat panel items, and because there were two variants of this locomotive (it was rebuilt with a bigger engine), 8 items have to be made to a slightly different design. All in all, that means 20 flat panels have to be created. I am about half way there at the moment in the 3D design process. To make this as inexpensive as I can, I am planning to put several items on each build connected by sprues, maximising the available area of the Finelines Microfine Green process. The build size is 127 x 127mm. Once the parts are built, I then have to investment cast the parts in Manganese Bronze so they can be used to create a vulcanised rubber mould for spin casting. I have had one side built so far in the Microfine Green process, just to test the quality: This side is quite small, 40 x 18mm in size. But you can see the surface is quite shiny and needs no further treatment before casting or painting. The sand box filler cap at the bottom edge is particularly fine, with the bolt heads on the cap support bracket even rendering: The cap is only 2mm in diameter. You can just see some steeping on the sand cap, and a little on the louves, but the majority of the panel is shiny, and this is due in part to the choice of build direction. By building each side flat, the top surface, which represents the major surface area, is not subject to stepping. This is the reason I am careful in selecting the best build direction. Another reason is that the resolution of most printing systems is greater in the X and Y directions than the Z, or depth, direction so you get crisper parts with higher detail. So, one part down, only 19 to go Link to post Share on other sites More sharing options...
dave flint Posted November 18, 2011 Share Posted November 18, 2011 Can I just say, as a casual observer, how impressed I am with the capabilities of this technology and how its is being used to very good effect ? please keep the images and threads coming, It is fascinating and much appreciated. Link to post Share on other sites More sharing options...
Petri Sallinen Posted November 20, 2011 Share Posted November 20, 2011 I have had one side built so far in the Microfine Green process, just to test the quality. Nice work Geoff. What kind of material the Microfine Green is? Is it hard enough to use the print e.g. making the individual model (yes, this might be too expensive, but interests me anyway) or is it breakable? The material looks like the wax — when you hook up these kind of parts together what kind of glue is suitable? Or what kind of paint is good for prints? Petri Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 20, 2011 Share Posted November 20, 2011 Petri, the data sheet for Microfine Grren can be found here: http://www.finelinep...ets/mfgreen.pdf However I do not pretend to understand most of the specifications. It is a quite hard material, like ABS plastic, and not a wax. I imagine you could glue it using CA adhesive like most plastics. I have not tried to paint it as I will be using it as a pattern for a mould. Over the weekend I visited one of the prototypes and did some more measuring and photographing. I have now finished the 3D drawings of 4 of the 20 panels and am working on the 5th. There are another 6 panels in a partly completed drawing form. Link to post Share on other sites More sharing options...
craigwelsh Posted November 20, 2011 Share Posted November 20, 2011 Do you have to account for shrinkage with the pewter you intend to cast with Geoff? I know Shapeways charge a fixed setup costs and I assume your maker is the same so it makes sense to maximise use of the print bed. I want to do some of the early british tank wagons so the photos Petri posted are very interesting. I'd intended on doing the print in 3 parts, two hollow ends and a centre section that would slot together. It would have resin and allow for extra weight inside. Looking at the quality achieved in the above print it might not even need an etched wrapper for the rivets. Though I would have to work out how to draw rivets around a cylinder! Link to post Share on other sites More sharing options...
hollywoodfoundry Posted November 22, 2011 Share Posted November 22, 2011 Craig, from previous tests, there was no shringage in the investment casting process needed to get high temperature resistant patterns for the pewter casting and very little in the pewter casting process. So, as a result, I am keeping it exact. I have had more problems with resin or urethane castings coming out wrong than I ever had with metals. One body I had cast for me was 95mm long, and of the 100 odd castings made in urethane, about half were wrong, with some up to 2mm short. I am therefore not keen on urethane as a medium any longer. Finelines certainly have a set-up charge, as multiple copies of the same thing are not that expensive. I always get extras as the investment casting process is destructive, and if it goes wrong, you need to have spares. Link to post Share on other sites More sharing options...
Petri Sallinen Posted November 22, 2011 Share Posted November 22, 2011 I have had more problems with resin or urethane castings coming out wrong than I ever had with metals. One body I had cast for me was 95mm long, and of the 100 odd castings made in urethane, about half were wrong, with some up to 2mm short. I am therefore not keen on urethane as a medium any longer. Yes, that´s right — dimensions vary with resin parts. I have used different kinds of epoxy resins and polyurethane resins since the 1980´s. Nowadays materials are much better, but dimensions with ready made castings still vary. Not so much in some cases — this depends on what kind of resin or mold rubber have been used. Tin cured mold rubber is cheaper but it shrinks, addition (=platinum cured) cured is much better, but it is expensive (some resin casting service companies also use polyurethane rubber for making molds, but the method is more expensive). There are also different kinds of polyurethane resins: some of them will shrink more (typically cheap ones) than others and some of them swell, because the reaction of resin components causes heat (when using fast cured resins there will be more heat than using slow cured resins). Before making anything it is better to discuss with resin casting service company about materials they use. With small parts cheap resins might be OK, but not with longer parts. Pewter casting sounds very interesting — I have never used this (I have only made small parts in cast brass and bronze by lost wax method). Please let me know if possible what is the typical run for pewter casting — they might have minimum runs. Pewter casting might be more expensive method than resin casting, isn´t it? Petri Link to post Share on other sites More sharing options...
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