AndyID Posted December 7, 2015 Author Share Posted December 7, 2015 Hi Andy, Is the prototype method out of the question? Drop in the rails, insert separate keys? Perhaps snap-off keys on the end of a stick. Then a drop of solvent or capillary cyano to secure them. Slaters do separate keyed track parts in 7mm scale. Martin. Hi Martin, It might be possible. I ran into a problem with the rails tilting in the chairs and (after an enromous amount of faffing around) I solved it by making the key side of the chair a flat vertical surface that is high enough to contact the head of the rail. There is nothing engaging in the slot in the outside of the rail at all. The inside of the chair is a bit more compliant and provides some "spring" force to keep the rail vertical and in place. That means, unlike the prototype, that the gauge reference is the key side of the chair. But the idea of using keys might still work although I suspect it will take a fair amount of experimentation to find out if it does. I've also found I can shave a bit off the inside of the chairs and snap the rail into the chair from above. I might end up using that trick on the diamond. With the long turnouts the chairs seem to be strong enough to allow the rail to thread all the way through although I cheat a bit and grind a little notch on the hidden bottom edge of the rail where I want the bend on the wings and check rails. Best regards, Andy Link to post Share on other sites More sharing options...
AndyID Posted December 7, 2015 Author Share Posted December 7, 2015 Andy to get back to the i3 printer ( maybe this should be in another thread) Would you recommend buy the frame separately (and all the bits separately ) and spending money on a high res extruder , or would you go for a complete " genuine " kit like the Prusa ( about 600 euros ) dave 600 Euros !!! I only paid $270 for mine. If you can get a decent price on a kit it I don't think it would cost a lot more than the sum of the components. For reference, I bought my kit from Folger Technologies in New Hampshire (no connection etc.) It seems a bit daft, but it might be worth importing one from the US, although I think you'll have to pay duty. I think the cost of the extra motors and nozzle I bought was under $30. Cheers! Andy Link to post Share on other sites More sharing options...
AndyID Posted December 7, 2015 Author Share Posted December 7, 2015 While I was minding the printer last night (BTW - that turnout turned out fine) I was playing around on Templot and curving various turnouts to try to understand what is hapening. It does take a fair bit of time to populate a turnout with all the chairs in CAD and I was wondering if I could cheat by producing a collection of straight turnouts of various sizes then bending them where they need to be curved. (I hope Martin isn't too horrified! Please don't beat me master!) Link to post Share on other sites More sharing options...
AndyID Posted December 8, 2015 Author Share Posted December 8, 2015 Threading the diamond was not a total success I thought I might as well take a shot at Martin's suggestion. On this sample I increased the chair slot enough to let the rail drop in and printed some wedges (not cut to length yet.). The "wedge" actually bears on the top and bottom of the rail and there is a raised projection on the inside that engages in the rail slot. I've found I need three points of contact to keep the rail vertical but I might take another shot at a more prototypical wedge. The wedges demonstrate how fine the printer's vertical resolution can be. For this print each slice is only 0.05 mm thick. The rail side of the wedge is really a series of steps, but the rise is only 0.05 mm per step. Link to post Share on other sites More sharing options...
trustytrev Posted December 9, 2015 Share Posted December 9, 2015 Hello, People in the UK might find http://www.reprappro.com/ worth a look.They do a variety of printer kits and have a lot of info available as well. Adrian Bowyer has been leading research and development of this technology for some time. trustytrev. Link to post Share on other sites More sharing options...
RMweb Gold Joseph_Pestell Posted December 9, 2015 RMweb Gold Share Posted December 9, 2015 Just had a quick look at that site. Will bookmark for future reference. It mentions some electrically conductive plastics. That might be useful in our context. Link to post Share on other sites More sharing options...
trustytrev Posted December 10, 2015 Share Posted December 10, 2015 Hello Andy, For chairs that are difficult for threading rail what about printing those with half the chair separate to be stuck on with solvent? PLA suitable solvents anyone? trustytrev. Link to post Share on other sites More sharing options...
RMweb Premium eldavo Posted December 10, 2015 RMweb Premium Share Posted December 10, 2015 No friendly solvents for PLA unfortunately. It's down to super glue, super glue or super glue practically. Cheers Dave Link to post Share on other sites More sharing options...
AndyID Posted December 10, 2015 Author Share Posted December 10, 2015 No friendly solvents for PLA unfortunately. It's down to super glue, super glue or super glue practically. Cheers Dave Failing that you could always use cyanoacrylate. Link to post Share on other sites More sharing options...
raymw Posted December 11, 2015 Share Posted December 11, 2015 Dichloromethane seems to weld it OK, no more unfriendly than other solvents, but you won't find it in your local model shop (post #34 of this thread) Link to post Share on other sites More sharing options...
autocoach Posted December 11, 2015 Share Posted December 11, 2015 Dichloromethane seems to weld it OK, no more unfriendly than other solvents, but you won't find it in your local model shop (post #34 of this thread) There is a reason it is not found at a local model shop: Highly toxic (Disclaimer I am not a chemist or elf and sarfty expert) Dichloromethane is the same compound as methylenechloride. It is a bit frightening to read the possible harm from breathing vapors of the stuff. https://www.cdph.ca.gov/programs/hesis/Documents/methylenechloride.pdf Have you tried Zap's Plasti-ZAP. This is available in hobby shops (US term). I have found it quite good for attaching plastic and non-plastic materials together. Link to post Share on other sites More sharing options...
raymw Posted December 12, 2015 Share Posted December 12, 2015 Most solvents are highly toxic, and I guess California has something to say about all of them. In the UK, it is only available for 'professional use, hence my comment wrt model shops. Fwiw, dichloromethane is often used in the 'drinking bird' type of 'toy' https://en.wikipedia.org/wiki/Drinking_bird Link to post Share on other sites More sharing options...
AndyID Posted December 14, 2015 Author Share Posted December 14, 2015 Works for me! Link to post Share on other sites More sharing options...
backofanenvelope Posted December 14, 2015 Share Posted December 14, 2015 Very impressive Andy. Once ballasted and painted will look great. Thanks for taking the time to show us. Link to post Share on other sites More sharing options...
hayfield Posted December 14, 2015 Share Posted December 14, 2015 Andy Very impressive Link to post Share on other sites More sharing options...
AndyID Posted December 14, 2015 Author Share Posted December 14, 2015 Thanks for all the encouragement! Separate keys were not working too well for me, so I went back to the original chairs, split the base into three parts and threaded the rails through the chairs. I left the paint on the check rails because the wheel treads don't polish the rust off. The other reason I left paint on the check and wing rails is because they were printed along with everything else. Link to post Share on other sites More sharing options...
AndyID Posted December 15, 2015 Author Share Posted December 15, 2015 This is a snip of the CAD work for the third turnout. The 2-D turnout layout (in red) is imported from Templot. The chairs are stored as "blocks" and each has a reference point that snaps to the intersection of the timber center and the rail gauge-line. Most of the chairs are "rubber stamped" on to the template. Once they are snapped to the correct location they are rotated into alignment with the rail. Some of the chairs consist of more than one block. The most complicated area is around the frog (still missing a few bits in this image). Once all the blocks are in place the timbers are extruded to the desired height. In terms of the CAD work, that's all there is to it. One of the things that appeals to be about this method is how it simplifies the actual construction of the turnout. It's just a matter of cutting and filing the rails and inserting them into the printed plastic base. So far I have not found it necessary to make any clearance or gauge adjustments after assembly. Link to post Share on other sites More sharing options...
mightbe Posted December 15, 2015 Share Posted December 15, 2015 Do the normal chairs automatically align perpendicular to the rails, or is this all done manually? Link to post Share on other sites More sharing options...
AndyID Posted December 15, 2015 Author Share Posted December 15, 2015 Do the normal chairs automatically align perpendicular to the rails, or is this all done manually? When they are snapped at the intersection of the rail and the sleeper they are all in the same orientation and have to be rotated into alignment with the rail. For 50% of the chairs that might mean about 180 degrees of rotation. It doesn't take long. The X rotation handle is simply snapped to the adjacent rail section. I don't know of a method in TurboCAD to automatically align them, but other CAD tools might have a way to do that. Link to post Share on other sites More sharing options...
RMweb Gold Joseph_Pestell Posted December 16, 2015 RMweb Gold Share Posted December 16, 2015 I know that you are primarily interested in this just for your own layout construction. But if someone did want to go into this commercially: - what sort of time is taken to create each drawing for the machine (assuming that you have already got a Templot template to start from)? - how long does each base take to print out and could it be done quicker on a more high-performance printer? - what is the material cost per turnout? Link to post Share on other sites More sharing options...
AndyID Posted December 16, 2015 Author Share Posted December 16, 2015 I know that you are primarily interested in this just for your own layout construction. But if someone did want to go into this commercially: - what sort of time is taken to create each drawing for the machine (assuming that you have already got a Templot template to start from)? - how long does each base take to print out and could it be done quicker on a more high-performance printer? - what is the material cost per turnout? Good Morning Joseph, Just caught your question before I go to bed With a bit more refinement I think it will take about 45 minutes to convert the Templot template for an average size turnout into a 3D CAD file. There are a couple of file processing steps after that to produce the file for the printer itself, but they are basically mechanical and require little thought. If the user created some "macro" models for particular crossing angles, the CAD time could probably be reduced quite substantially. I have not bothered to do that because I don't plan to make all that many turnouts. At the moment, the print time for a decent size turnout is about 75 minutes. That might come down a bit with some optimization, but I think it's still going to be a substantial chunk of an hour. Using this type of material and additive process I don't think it will get much faster, even with a more expensive printer. But the printers are relatively inexpensive, so it would be easy to add more printers to keep up with increased volume demand. I suspect a printer would be able to pay for itself quite quickly. The raw material cost (I'm using PLA) is peanuts. I can buy a one kilogram spool of the stuff for $20. I'm not sure how many turnout bases I can get from a kilogram, but I suspect it's a very large number. The timbers are not solid plastic. The inner layers consist of a lot of air. That's done largely to reduce the print time, but it also substantially reduces the weight. Cheers! Andy Link to post Share on other sites More sharing options...
RMweb Gold Joseph_Pestell Posted December 16, 2015 RMweb Gold Share Posted December 16, 2015 Thanks, Andy. On that basis, there is certainly scope for someone to make bespoke point kits that would come in at a price well below C&L and reasonably competitive with the ready-to-lay options. Exciting stuff! I had been considering laser cutting of bases but that still leaves a requirement for chairs to be glued in place. Link to post Share on other sites More sharing options...
trustytrev Posted December 16, 2015 Share Posted December 16, 2015 Hello, The main thing about 3D printing is the need to master the various skill sets required.CAD programs,3D printer maintenance and repair,possibly building your own.You will probably need skills with electronics which means expanding basic knowledge in that field as well.You need knowledge of track technology both past and present and the skills to construct it as well.You also need to be well versed in the use of Templot as peoples expectations will far exceed the capabilities of the technology however much it progresses. Before you know it you can't find enough time in the day for it all. Add to that the time needed for railway modelling and the days are too short. I forgot about life in general which has a habit of introducing unexpected things that derail(what a pun) everything. You can add learning about computers to the mix as well. It is all good interesting and fun though. I just need to take my tablets. trustytrev. Link to post Share on other sites More sharing options...
hayfield Posted December 16, 2015 Share Posted December 16, 2015 trustytrev I think the idea is that someone starts up a cottage industry to supply the prints either themselves or via one of the printing companies As for Andy, he seems to enjoy this development and its to assist him modelling. He has stated that if he were to do this commercially (which he has said he is not) then he would approach the design in a different manor which will be less time intensive. look at what Modelu3D are doing and the results being achieved. Before this will have an impact on the likes of C&L/Exactoscale let alone Peco there is a lot of development to do, but its a fantastic start Link to post Share on other sites More sharing options...
AndyID Posted December 17, 2015 Author Share Posted December 17, 2015 trustytrev I think the idea is that someone starts up a cottage industry to supply the prints either themselves or via one of the printing companies As for Andy, he seems to enjoy this development and its to assist him modelling. He has stated that if he were to do this commercially (which he has said he is not) then he would approach the design in a different manor which will be less time intensive. look at what Modelu3D are doing and the results being achieved. Before this will have an impact on the likes of C&L/Exactoscale let alone Peco there is a lot of development to do, but its a fantastic start Hi John, I would be interested to see what people thought of an exhibition model that used it. Unfortunately it's a bit unlikely that my layout will ever be exhibited in the UK, and if I did take it to a show in the US the reaction would be "entertaining". Andy Link to post Share on other sites More sharing options...
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