What the prototypes found — board angle and sensor height

Question

Is a design that is right in CAD also right in actual use?

Background

I worked out RYF-001 by printing more than six versions on an FDM 3D printer. Not only to compare shapes in the hand: by fitting the internals and actually using them in games, I found a number of problems that had not been visible on screen.

Here I record two of them.

Board mounting angle and cable interference

The first design

In the first design, the main-click board was mounted parallel to the base — that is, horizontal. In CAD, there was no problem with that at all.

The problem found

Actually using the prototype showed that the cable running from the lower rear edge of the board touched the mouse pad. It was a problem I could not have noticed while I was only looking at the shape.

The fix

I revised the mounting angle of the board so the cable no longer touches the mouse pad.

Sensor mounting height

The problem found

The other was the mounting height of the sensor.

Using the prototype, something felt off. On investigation, the sensor had not been mounted at the right height, and the LOD (lift-off distance: the height at which the sensor responds) was only around 1.5 mm. As a result, the DPI felt lower than on the mice I normally use.

What a sensor reads changes with its distance from the mouse pad. The sensor was mounted too high, so it was not delivering the performance it should.

The fix

I adjusted the sensor’s mounting height little by little until nothing felt off.

Observations

Neither problem was visible on the CAD screen. They were found when the internals were actually fitted and the mouse was moved by hand.

Next, in shapes maketh aim — 06, I write about the problem, also found through prototyping, that led to the largest design revision: the internal structure.