Summary

Another prototyping aid. This time a way to add 'controls' to your project. Like the other items in this series the idea is that you can glue the bracket down to a piece of scrap acrylic or polycarbonate to keep everything in one place. This is shown in one of the images where it is holding Quadrature Knobs from AdaFruit which are providing a soft API for my graphics application.

See instructions for details of the design.

Instructions

I drew this up in TurboCAD like my other designs. The interesting bit is that it prints "sideways" because it would be difficult to bridge, and the top part is only 2mm thick in order to accommodate the short threads of the AdaFruit knobs.

On the ends you will notice some "hold down" tabs. On long pieces like this that want to lift on the ends, I've found that putting a 1mm thick piece of plastic which connect to the piece with a .25mm thick x 1mm "connector" is sufficient to keep the part in place and held down until enough of the structure has been printed that it will stay flat on its own. Ideally the hold down tabs have rounded corners but in this case they are small enough that I didn't see it as an issue.

The other thing is that the center supports are required as these knobs have a 'push button' function (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.

Frob Knob Bracket