Customizable Battery Tray for FlexRC Mini Owl

thingiverse

Those running FlexRC Mini Owl quadcopters with motors on top frame plates pointing downward may encounter two very inconvenient bolt heads when trying to mount their battery. These bolts stick up above the top plate surface, and you're left to try perching your battery on top of them. This battery tray sits over the exposed bolt heads, providing a secure mount for your battery. If you run only one type of battery on your Mini Owl, this battery tray can be configured to be bolted to the quadcopter by specifying a bolt shank diameter, bolt head diameter, and bolt head inset. If you run multiple types of batteries, as in my case, then this tray can be configured to just sit over the exposed bolt heads, allowing for different trays to be easily swapped in/out. This is very customizable and should be able to be used for a variety of batteries. It's likely that this could also be used with other quadcopters in the Owl range. Settings I use for a Tattu 450 mah 2 cell lipo, where the tray just sits over the bolt heads: bolt_c_c = 43.5; //center-to-center distance between bolts bolt_shank_dia = 6; //shank diameter of bolt (where bolting battery tray to quad frame) - make same diameter as bolt head for tray that will simply sit over bolt heads bolt_head_dia = 6; //bolt head diameter of bolt (where countersinking bolt, or making tray to sit over bolt head) bolt_head_inset = 1; //depth to countersink bolt head to (applicable if bolt shank and head settings are different diameters) batt_len = 62.5; //length of the battery, plus a mm or so of wiggle room batt_w = 17.4; //width of the battery, plus a mm or so of wiggle room base_t = 2; //thickness of the base plate base_corner_r = 7; //corner radius of plate external corners - must be a sensible value that works with plate width - some experimentation may be needed finger_t = 2; //thickness of battery holding fingers finger_w = 8; //width of battery holding fingers finger_h = 7.5; //height of battery holding fingers hole_web_t = 3; //width of side walls - should be at least as bit as finger_t parameter center_hole_r = 4; //inside corner radious of plate internal corners - must be a sensible value that works with plate width - some experimentation may be needed For a Tattu 850mah 3 cell lipo, where the tray just sits over the bolt heads, I use: bolt_c_c = 43.5; //center-to-center distance between bolts bolt_shank_dia = 6; //shank diameter of bolt (where bolting battery tray to quad frame) - make same diameter as bolt head for tray that will simply sit over bolt heads bolt_head_dia = 6; //bolt head diameter of bolt (where countersinking bolt, or making tray to sit over bolt head) bolt_head_inset = 1; //depth to countersink bolt head to (applicable if bolt shank and head settings are different diameters) batt_len = 62.5; //length of the battery, plus a mm or so of wiggle room batt_w = 17.4; //width of the battery, plus a mm or so of wiggle room base_t = 2; //thickness of the base plate base_corner_r = 14; //corner radius of plate external corners - must be a sensible value that works with plate width - some experimentation may be needed finger_t = 2; //thickness of battery holding fingers finger_w = 8; //width of battery holding fingers finger_h = 7.5; //height of battery holding fingers hole_web_t = 3; //width of side walls - should be at least as bit as finger_t parameter center_hole_r = 4; //inside corner radious of plate internal corners - must be a sensible value that works with plate width - some experimentation may be needed Print Settings: Printer Brand: Printrbot Printer: Simple Black Rafts: No Supports: No Infill: Whatever you like - I tend to like 20% Notes: This is a non-structural part, so can be printed fairly light (ie, infill), and made fairly thin (just thick enough to smooth out the exposed bolt heads). Note that the external and internal corner radii can be set free-form, so sensible values must be chosen. A large outer radius, on a fairly narrow battery tray, won't provide great results, for instance. How I Designed This: OpenSCAD allows this battery tray to be highly customizable. I love OpenSCAD! This uses the great Chamfers-for-OpenSCAD library from SebiTimeWaster. While the library is included in this file, the library can be found at the link below, and is well worth incorporating into OpenSCAD designs. https://github.com/SebiTimeWaster/Chamfers-for-OpenSCAD