{"product_id":"slim-planetary-gearbox-for-nema-17","title":"Slim planetary gearbox for Nema 17","description":"\u003ch3\u003eWhat is this?\u003c\/h3\u003e\u003cp\u003eA compact (planetary) gearbox that can be mounted on top of a Nema 17 motor to increase the torque at the cost of speed.\u003c\/p\u003e\u003cp\u003eIn this case, the ratio is 1:4.36 (the output shaft moves once every 4.36 rotations of the stepper motor).\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eIt has been designed to replace these two large gears\u003c\/p\u003e\u003cfigure class=\"image image-style-side\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_54ddcd618500e.png\"\u003e\u003c\/figure\u003e\u003cp\u003ewhich took up a lot of space and were suboptimal for my project.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThe gearbox consists of a sun gear with 11 teeth and 4 planets with 13 teeth each. The outer ring has 37 teeth. Note that all teeth are prime numbers, which reduces wear on the teeth.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003ch3\u003eWhy another planetary gearbox?\u003c\/h3\u003e\u003cp\u003eThere are many planetary gearboxes out there like\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/makerworld.com\/en\/models\/464228\" rel=\"nofollow noopener\"\u003ehttps:\/\/makerworld.com\/en\/models\/464228\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/makerworld.com\/en\/models\/540208\" rel=\"nofollow noopener\"\u003ehttps:\/\/makerworld.com\/en\/models\/540208\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/867552-planetary-gearbox-for-nema-17\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/867552-planetary-gearbox-for-nema-17\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/45205-nema-17-cycloidal-gear-box-prototype\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/45205-nema-17-cycloidal-gear-box-prototype\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/44974-nema-17-stepper-51-planetary-gearbox-with-5mm-shaf\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/44974-nema-17-stepper-51-planetary-gearbox-with-5mm-shaf\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/202734-801-nema-17-planetary-gearbox\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/202734-801-nema-17-planetary-gearbox\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/853296-mini-planetary-gearbox\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/853296-mini-planetary-gearbox\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca target=\"_blank\" href=\"https:\/\/www.printables.com\/model\/281222-nema17-planetary-gearbox\" rel=\"nofollow noopener\"\u003ehttps:\/\/www.printables.com\/model\/281222-nema17-planetary-gearbox\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003ebut many have restrictive licenses that limit one's ability to use them in their own projects or are missing the parametric step files.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThat is why I created my own planetary gearbox that can be used without restrictions in any project.\u003c\/p\u003e\u003ch3\u003eHow has this model been created?\u003c\/h3\u003e\u003cp\u003eI primarily design my models in Shapr3D, which unfortunately does not have the ability to generate gears.\u003c\/p\u003e\u003cp\u003eFinding a good tutorial that explains how planetary gears are made was quite difficult as well, which is why I document it here, in case someone else struggles with it too.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThis site was useful for finding different combinations of teeth that work and which ratios one will get: \u003ca target=\"_blank\" href=\"https:\/\/planetarygenerator.mateuszdrwal.com\/\" rel=\"nofollow noopener\"\u003ehttps:\/\/planetarygenerator.mateuszdrwal.com\/\u003c\/a\u003e\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThe gears were generated in Fusion 360 with the \u003ca target=\"_blank\" href=\"https:\/\/apps.autodesk.com\/FUSION\/en\/Detail\/Index?id=9029586664984391977\" rel=\"nofollow noopener\"\u003eHelical Gear Generator\u003c\/a\u003e and the following settings:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eRadial System\u003c\/li\u003e\n\u003cli\u003ePressure Angle: 25°\u003c\/li\u003e\n\u003cli\u003eModule: 1mm\u003c\/li\u003e\n\u003cli\u003eTeeth: 11\/13\/37\u003c\/li\u003e\n\u003cli\u003eBacklash: 0.1mm\u003c\/li\u003e\n\u003cli\u003eGear Thickness: 5mm\u003c\/li\u003e\n\u003cli\u003eHandedness: Right for planet and ring, left for sun gear\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eThe ring gear was created like described in \u003ca target=\"_blank\" href=\"https:\/\/www.youtube.com\/watch?v=5a1w9daIybc\" rel=\"nofollow noopener\"\u003ethis tutorial\u003c\/a\u003e, but without the mentioned adjustments (I simply generated the ring gear with a backlash of -1mm and then subtracted it from a cylinder to create the internal ring gear).\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThe gears were then incorporated into a frame that holds them in place in Shapr3D. I went through many iterations until I ended up with the design that you see here. The current design is optimized to be as slim as possible, the gearbox ended up with a height of only 18.8mm, which is a bit taller than \u003ca target=\"_blank\" href=\"https:\/\/makerworld.com\/en\/models\/464228\" rel=\"nofollow noopener\"\u003ethis model\u003c\/a\u003e (according to the slicer it has a height of 17mm, but the screw heads are not in the lid, with them included, it would have a height of 20mm).\u003c\/p\u003e\u003ch3\u003eMinor improvements\u003c\/h3\u003e\u003cp\u003eWhile designing, I thought that it would be nice to add bearings, but they don't seem to be an improvement. The option is still there in the print profile if you already have the bearings.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eIf you want, you can add a bit of grease between the gears to reduce friction\/noise. I used the same grease that I use for the z-axis of my printer. In my case that is the \"liqui moly silicone grease\", but other ones like super lube or the one included with the printer should work as well. In the worst case, you would have to reprint the parts, but with only a few grams of filament that shouldn't be much of an issue.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003ch3\u003eParts for assembly\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e4x M3 x 20mm screws\u003c\/li\u003e\n\u003cli\u003e(8x MR63 bearing or 673 bearing) (optional)\u003c\/li\u003e\n\u003cli\u003e(1x MR128 bearing) (optional)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eFor bearings, you might notice that the names will have a ZZ or RS at the end, like MR128ZZ or MR128RS. They are the same bearing with the same dimensions. The suffix refers to how the bearings are sealed. The ZZ ones have a metal lid that is pressed onto the bearing and will only keep out dirt. The RS ones have a rubber seal, they are not waterproof but make it harder for liquids to enter the bearing. For this project it doesn't really matter which ones you get, and like mentioned above, there is \u003cstrong\u003elittle benefit\u003c\/strong\u003e to adding bearings. \u003c\/p\u003e\u003ch3\u003eHow to assemble\u003c\/h3\u003e\u003cp\u003e0. First start by printing all the necessary parts, you should have\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e4 gears with holes\u003c\/li\u003e\n\u003cli\u003e1 gear that is taller than the other ones (= the sun gear)\u003c\/li\u003e\n\u003cli\u003ea carrier (the thing with 4 poles and a hole in the center)\u003c\/li\u003e\n\u003cli\u003ea body\u003c\/li\u003e\n\u003cli\u003ea lid\u003c\/li\u003e\n\u003cli\u003ean output shaft (either regular or loose fit, try the regular one first)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eIf you are having problems fitting the parts together, you might have to calibrate the flow rate and pressure advance (flow dynamics) for your filament. I had some filaments that printed perfectly and others where the parts were a bit too large\/small.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eNote\u003c\/strong\u003e: The carrier should be printed separately from the other parts. Otherwise, the thin poles might print imperfectly.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e1. Find the carrier\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_9c6252ab02309.png\"\u003e\u003c\/figure\u003e\u003cp\u003e(1.a) If you have chosen the version with the MR128 bearing, insert it into the bottom of the carrier. You might need a bit of force to get it in.\u003c\/p\u003e\u003cp\u003e(1.b) If you have MR63 bearings, you should insert two of the small bearings in each planet gear. \u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e2. Add the sun gear into the middle of the carrier:\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_b0cec95534d57.png\"\u003e\u003c\/figure\u003e\u003cp\u003e3. Place the body on the Nema 17 stepper with the carrier and sun gear in the middle, like this:\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_74c2152f78e87.png\"\u003e\u003c\/figure\u003e\u003cp\u003eIf the stepper shaft is not going into the sun gear, you need to rotate it until it goes in.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e4. Add the planets to the carrier (you might have to wriggle them around a bit, to make them go in):\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_5a3fa829730d8.png\"\u003e\u003c\/figure\u003e\u003cp\u003e5. Now place the output shaft on the carrier like this:\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_dd9a233ad982c.png\"\u003e\u003c\/figure\u003e\u003cp\u003e6. Place the lid on top\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_a8a0f709da524.png\"\u003e\u003c\/figure\u003e\u003cp\u003e7. Then add the four M3 x 20mm screws in the four holes to complete the assembly. Note that the screws should screw into the holes of the stepper motor.\u003c\/p\u003e\u003cfigure class=\"image\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_2867d0f37460a.png\"\u003e\u003c\/figure\u003e\u003ch3\u003eHow to use the planetary gearbox?\u003c\/h3\u003e\u003cp\u003eThe planetary gearbox output shaft has a pattern that is supposed to be like a torx bit. There is an “output receiver” in the attached step file that you can use for your own model to attach it to the gearbox.\u003c\/p\u003e\u003cfigure class=\"image image-style-side\"\u003e\u003cimg src=\"https:\/\/makerworld.bblmw.com\/makerworld\/model\/DSM00000000774955\/design\/2024-11-10_6db609ba12a7a.png\"\u003e\u003c\/figure\u003e\u003cp\u003eUsing a different output shaft is an option as well, that is why I included the step files.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eJust keep in mind that I chose the “torx bit” design for a good reason. Before that, I used something like a six head bit for the output shaft. This worked, but when the motor applied a lot of torque (which you want to do with a gearbox) the output shaft would slip and over time the output receiver became round and failed to grab onto the shaft.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThe torx bit is less likely to slip, at the cost of the stepper motor skipping steps if it can't provide enough torque, but that is desirable, especially if you want to use the stepper in combination with a driver that can detect stalls like a TMC2209.\u003c\/p\u003e\u003ch3\u003eRegarding License\u003c\/h3\u003e\u003cp\u003eMakerworld offers an exclusive program through which one can earn more points, at the cost of only sharing the model here.\u003c\/p\u003e\u003cp\u003eTo prevent others from posting the model on different platforms, you are required to license the project under a “Standard Digital File License”. Most of my models are Makerworld exclusive, which is why I want to give the program a try.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eI only selected that it is 14-Day Exclusive. After that time period, the program ends, and I will license this project as CC0 (public domain), so you can use this in any project, sell it or do whatever you want to do with it.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eYou are not required to note that you used my model for your own project, but I would love to see what you used it for.\u003c\/p\u003e\u003cp\u003eDesign by luro02 on MakerWorld (license: CC0).\u003c\/p\u003e","brand":"Mymadmanlab","offers":[{"title":"Default Title","offer_id":67368167244080,"sku":null,"price":4.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0987\/0809\/5280\/files\/0_bf0d164a-252c-4358-9e1d-eea5557c8c5c.png?v=1784024348","url":"https:\/\/mymadmanlab.com\/products\/slim-planetary-gearbox-for-nema-17","provider":"Mymadmanlab.com","version":"1.0","type":"link"}