Flexible Keypad Button/s in Nylon
by Taulman, published
Some systems I design are large and may have multiple keypads. Usually a main interface, then other small units for minor mech adjustments or mech calibration.
As keypads are usually tooled and die cut, even prototypes are very expensive. Having the ability to quickly 3D Print a flexible keypad can make prototyping faster, less costly and allow for a true Form-Fit-Function evaluation.
The .stl is not meant to be printed on it's own. Rather it's meant to be "step-and-repeated" in an array or placed in a desired pattern.
It is then Boolean added to a box/rectangle and then rotated such that the buttons are on a side wall.
Then you simply print the new .stl as a "hollow" part.
.4mm nozzle or smaller and .12mm layers
Print at 1 perimeter and 2 solid layers. The 2 solid layers act to hold the part to the table and the 1 perimeter is the thickness of the keypad.
After the print has reached the height you need, just stop the print.
You can then cut off the side with the keys using scissors as well as a desired outline.
The pliability of nylon is used in the flexible "S" joint around the key.
Because there's no delamination in the 618 nylon, the keypad is completely flexible and won't crack or frey at thread boundaries or split apart over time.
Most of my designs use a build up of :
- The Printed Circuit Board
- The Momentary Switches 8mm in this case
- Spacer to mount the keypad
- Then Keypad
Any size button can be designed to use this method. All you need is the flexibility of the nylon as well as a "S" joint built into your button.
To help others in their button designs, I've added the profile I used in .dxf format.
In the close up photo, you can see the single layer along with the "S" joint.
I have a new customer that want's a tubular shaped Keypad with a rocker thumb switch and two directional switches meant to be mounted on a activation handle. So instead of printing on a rectangle, I'll be printing on a tubular curve.
The material can be found here www.taulman3D.com