MicroYo - The mostly-printed mini yoyo

thingiverse

Changelog: (7-16-2016 3:30pm EST) -- If you downloaded the pocket model before 3pm EST on July 16th make sure you re-download, the version that was uploaded had an issue with extremely thin walls and would cause failures when printed, the new version should correct this. I've recently taken an interest in yoyo-ing again, but this time I'm focused more on the mini throws you can take anywhere, like the one drop dingo, mighty flea and the not yet released executive. They're all unresponsive yoyos with a compact frame and unique playstyles, and I wanted to approach that from a 3d printed route. The issue with 3d printing such a small yoyo is that it's impossible to reach the required 54-68 gram weight range, but there are solutions, one of which I've employed in this design. There are two versions, one has a diameter of 48mm and an assembled width of about 36mm, making it small and playable, but not exactly pocket friendly. The second is almost 1/3 slimmer in width with a slightly larger diameter, making it much more pocket-friendly at the cost of some stability from its thinner stance. This is a mostly 3d printed mini yoyo with customizable weights and a completely extreme rim weight to body weight ratio (60-90% of the weight is on the rim, depending on infill density and the washer size used). The bulk of the weight of these comes from the use of a thrust bearing washer with a minimum internal diameter of 0.75" and a width of 0.125", the maximum outer diameter supported is 1.75". A pair of bronze thrust washers at the maximum supported size should bring a MicroYo printed at 15-20% density to an assembled weight of around 70 grams, making it a bit heavy, but perfect for slower play. If you want to print at higher densities, or want a lighter yoyo, just use a smaller or thinner thrust washer to compensate. Another option is to sand down the thrust washers in order to make small weight adjustments. The calculator I use to estimate the weight of these washers is located on this site: http://www.onlinemetals.com/calculator.cfm The weight of the yoyo's hardware is approximately 6 grams (m3 x 16mm bolt, m3 nut, C-sized yoyo bearing and flowable silicone response pads), the weight of the printable parts themselves are estimated in Cura. The hardware needed for assembly is one m3x16mm or m3x14mm bolt, an m3 nut, and a standard C sized yoyo bearing (available from nearly any online yoyo shop, I personally like the buddha whipple and ripple bearings from yoyobestbuy) as well as flowable sililcone to create the response pad system. And of course, plenty of strings. The thrust washers can be found on ebay and mcmaster-carr, as well as in hardware stores. Photos will be added as soon as my thrust washers come in, for now the cover image is a prototype using Alumalite two-part polyurethane resin to fill the void, which is also option if you want an extremely light yoyo that plays surprisingly well. Print Settings Printer: Kossel Mini Rafts: Doesn't Matter Supports: Yes Resolution: 0.15mm or better Infill: 15-50% Notes: Infill density is dependent mainly on how heavy the washers you buy are, with heavy bronze washers I went with 15% to hit my target weight, for lighter aluminum you would want a much higher infill density. PLA is the preferred material as it is stronger, ABS tends to snap at the bearing seat. Print at as high a resolution as you can for a smoother body; The smoother it is, the better it will play.