Terrier Loco

thingiverse

This is a 1/32 scale interpretation of a Terrier locomotive based on the drawing of "Bodiam" by Leslie Darbyshire from the Colonel Stephens Society's website: http://colonelstephenssociety.co.uk/onewebmedia/KESR%20loco%20Bodiam%20(1)%20WM.jpg. The image is used with permission. The Terrier locomotive is relatively small, and its scale looks tiny compared to G-scale (circa 1/22) models. I have taken creative liberties in interpreting the drawing for this model and tried to make it easy to print. Some details like proper hook connectors on the buffers are not included; however, alternate bodies with various bits of detail are provided. Some Terriers have horizontal pipes from the tanks to the funnel box, which can be challenging to print unless the entire assembly is printed together. This would require removing support structures inside, making it difficult to achieve. The "Short Frame" has been reduced in scale length to allow for a single part print on 200mm beds. Everything else should also print on these beds. There have been comments about the coal bunker being too high, and I based this model on 32646 that ran at Hayling. However, there are many others with lower bunkers, so I added a "Low Coal" Body to better represent these models. The main goal is to have fun! The design uses M3 sleeved inserts in the body parts and wheels for 8mm long M3 hex head screws to hold everything together. Two "arduino smart Car Robot Plastic Tire Wheel with DC 3-6v Gear Motor" are used - be careful to get those with twin shafts, not the one with a single shaft. A slot is provided in the body for the slide switch on the "RC ESC 20A Brush Motor Speed Controller." There's room for the controller, an RC receiver, and a 1000mAh 2S lipo in the main body. Alternatively, you can use a Wemos ESP8266 with sound card and (and the same RC motor controller) to get a DCC-controlled loco with sound. See https://github.com/dagnall53/ESPMQTTRocnetSound. The latest version of the software now allows for chuffing and tooting at the same time: https://www.youtube.com/watch?v=Pg5r6MZDhww. A video showcasing some tests of the spring concept can be found here: https://youtu.be/I7FIhVYsUMA. The early F360 design process is shown in this video: https://youtu.be/74LDF40UaGs, but a lot has changed since then. The body and frame are screwed together with M3 * 8mm screws and 4mm M3 sleeved insert holes (total of four for the smoke box to hold it down). The buffers' beams are screwed on using two 1.8mm by 12mm screws each. Four more 1.8mm diameter *12mm long screws hold down the cab top. The steps need to be glued on. Parts list: * M3 8mm bolts, 16 needed * 1.8*12mm screws, 8 needed * 3mm shaft, 51mm long 1 needed * 3mm*7mm*3mm Ballraces, 2 needed * Motors: 2 needed * Electronics: + 10A RC Brushed ESC + 1500mAh 2S lipo + Extension cable for LIPO charge socket (to make charging available from rear bunker) + RC Receiver or: - Wemos D1 mini + - Adafruit MAX98357 I2S Class-D Mono Amp - 40 mm loudspeaker I painted my body matt black. To finish it off, I added some 0.7mm brass wire handrails and Slaters 7951L - 7mm - 12 x 3.2mm Brass Handrail Knobs. WARNING: Make sure the screws connecting the con rod to the wheel are well secured with Loktite screw lock (or similar) and well secured before testing the motors. If not, one side will tighten up and lock the con rod, either breaking it or putting the wheel sides out of alignment. I've done this too many times now and need to be more patient!