PatriotClass Posted August 8, 2021 Share Posted August 8, 2021 (edited) This summer I am experimenting with 3D printing 4 mm scale signals for my LMS layout. TheSignalEngineer posted a great prototype picture of a Midland twin signal here and I decided without any hasitation to use this for my second project. There are four positions on my layout, where I need a signal like this, so it makes really sense to build a reproduceble 3D model. Like most of you I used mini servos. One of them is a SG90 type from EBAY, the other is a similiar type from the Digikejis Servo Starter set. I can't recomend the Digikejis - it's very noisy and rough geared - but it works so far. The model consits of four moulds: The signal post, the arms, the servo mounting and a connection part (blue) that is for planting the signal. The control wires are 0,8 mm brass, but will look better in 0,6 mm or even less. I was not shure about printing this L-shaped hinges from resin, but they work well, although they hve to be thicker than brass. The two lanterns have 3mm openings in the bottom to fit there either a warm-white LED or a conventional lamp. I wanted to model the back-blinders aswell, so there is a non prototype connection to the arms... well, a compromise. I am controling the servos by an Arduino UNO. This 10 GBP controller can operate up to 12 servos, so using these SG90 servos (1,8 GBP) it's really a budget-friendly way to signal your layout. So let's take the model to paint shop... See it in motion on YouTube Thanks for all your information! Below I uploaded the STL files for anyone who is interested: MT_root.stl MT_ServoMount.stl MT_signalBody.stl MT_Arm.stl MT_L_connector.stl Edited August 8, 2021 by PatriotClass Forgot a picture 5 4 2 Link to post Share on other sites More sharing options...
RMweb Gold Harlequin Posted August 8, 2021 RMweb Gold Share Posted August 8, 2021 This looks very good! Have you thickened parts over the prototype dimensions to ensure they will print? What printer did you use? 1 Link to post Share on other sites More sharing options...
PatriotClass Posted August 9, 2021 Author Share Posted August 9, 2021 (edited) 16 hours ago, Harlequin said: This looks very good! Have you thickened parts over the prototype dimensions to ensure they will print? What printer did you use? I used a three year old ELEGOO mars printer. So the print took 7 hours. I thickened just the hand rails and the safety ring at the top end of the ladder. These parts are printed in a diameter of 0,8 mm. I tried 0,6, on my Claughton handrails, but this won't bring satisfying results. To get here more prototype look, I suggest to knip off the resin handrail and replace it by brass. The arms have double the thickness of the prototype to give more stability, but I think, here it's possible to go thinner. Edited August 9, 2021 by PatriotClass 1 1 Link to post Share on other sites More sharing options...
RMweb Premium uax6 Posted August 9, 2021 RMweb Premium Share Posted August 9, 2021 (edited) The blinders look a bit odd, they are usually fixed via the spindle that the arm pivots on, not via a strap around the edge of the lamp.... The rest is pretty good! Andy G Edited August 9, 2021 by uax6 1 1 Link to post Share on other sites More sharing options...
Paul Cram Posted August 10, 2021 Share Posted August 10, 2021 5 hours ago, uax6 said: The blinders look a bit odd, they are usually fixed via the spindle that the arm pivots on, not via a strap around the edge of the lamp.... The rest is pretty good! Andy G They are fixed to the arm but the strap fits between the post and the lamp Link to post Share on other sites More sharing options...
Paul Cram Posted August 10, 2021 Share Posted August 10, 2021 5 hours ago, uax6 said: The blinders look a bit odd, they are usually fixed via the spindle that the arm pivots on, not via a strap around the edge of the lamp.... The rest is pretty good! Andy G They are fixed to the arm but the strap fits between the post and the lamp Link to post Share on other sites More sharing options...
PatriotClass Posted August 10, 2021 Author Share Posted August 10, 2021 13 hours ago, uax6 said: The blinders look a bit odd, You're right! It's not a good compromise, indeed. 8 hours ago, Paul Cram said: They are fixed to the arm but the strap fits between the post and the lamp That's possible to do so in the model, but I fear that the attatchment of the lamp may become to weak, when I give space for the strap. But I did it the lazy way: I applied a drop of super glue to fix the arm and the blinder to the shaft. When the glue has set, I removed the strap and, here it is! So I will keep the strap just as an assembly aid to fix arm and blinder exactly. 2 1 Link to post Share on other sites More sharing options...
RMweb Premium uax6 Posted August 10, 2021 RMweb Premium Share Posted August 10, 2021 If you make the pin that holds the arm to the post a loose fit in the post, but tight on the arm and the blinder, then it will be possible to get the blinder to move with the arm properly. Looks better already mind! Andy G 1 Link to post Share on other sites More sharing options...
PatriotClass Posted August 10, 2021 Author Share Posted August 10, 2021 35 minutes ago, uax6 said: If you make the pin that holds the arm to the post a loose fit in the post, but tight on the arm and the blinder, then it will be possible to get the blinder to move with the arm properly. That's what I did and it works fine. Link to post Share on other sites More sharing options...
PatriotClass Posted August 11, 2021 Author Share Posted August 11, 2021 (edited) Just catching the sun for drying. Here I made another one inspired by Mr Warburton's book. I wanted to try printing a lattice post and mount two arms on one post, The M2 screws at the arms are provisoric. The whole signal is one mould, exept the mechanics and arms and reaches up to 16.5 centimeters. I am just wondering if I should put in the arms colour filters or use a duo-LED that can display red and green by changing it's polarity. If anyone is interested in the STL files, feel free to write a message. Edited August 11, 2021 by PatriotClass 5 1 Link to post Share on other sites More sharing options...
MRH Posted November 18, 2021 Share Posted November 18, 2021 These are really very good. Well done. I was thinking of producing some Midland signals as well as LMS UQ's. Would be very interested in the STL files. 1 Link to post Share on other sites More sharing options...
PatriotClass Posted December 2, 2021 Author Share Posted December 2, 2021 Thanks for the interest. Below I have uploaded the STL files and a dxf-Export in case, anybody wants to modify the model. The Servo mount is made for these chinese mini hobby servos. LMS_Sockel.stl RedArm.stl YellArm.stl 1147782237_LatticeTriple.stl DogLeg.stl 1546055458_LMS_Junction1.dxf 3 1 Link to post Share on other sites More sharing options...
MRH Posted December 10, 2021 Share Posted December 10, 2021 Many thanks for these. Will keep me busy over Xmas! Cheers. Link to post Share on other sites More sharing options...
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