Frob Knob Bracket

thingiverse

Another prototyping aid, adding 'controls' to your project, like others in this series, where you can glue the bracket down to a piece of scrap acrylic or polycarbonate for everything to be in one place. This is shown in an image, holding Quadrature Knobs from AdaFruit which provide a soft API for my graphics application. See instructions for details of the design. Instructions I drew this up in TurboCAD like other designs. The interesting bit is that it prints "sideways" because bridging would be difficult, and the top part is only 2mm thick to accommodate short threads of the AdaFruit knobs. On the ends you'll notice some "hold down" tabs. For long pieces like this prone to lifting at the ends, I've found that a 1mm thick piece of plastic connecting with a .25mm thick x 1mm "connector" is sufficient to keep the part in place until enough structure has been printed to stay flat on its own. Ideally, hold down tabs have rounded corners but in this case they are small enough that it's not an issue. The other thing is that center supports are required as these knobs have a 'push button' function where you can press the knob down as a momentary push button. All in all it works well. On the application board, you can see the power connector adapter and standoffs being used as well. This is a very handy way to prototype a system out of "pieces" that come from places like Sparkfun or AdaFruit.