HP45 power switch lubrication without opening calculator?

[teenix]

The switch is quite basic in operation.

A contact connects via rounded edges onto the plated circuit board pads and fits into a recess under the switch moulding. It is bent in such a way as to provide outward pressure onto the board when assembled.

The plastic switch (from memory) slides over a plastic protrusion tensioned by the spring contact which gives it the snap on, snap off feel. I doubt the board contact would offer much resistance to movement although thick grime can build up over time.

Rather than just push it sideways, you can push down slightly on the switch as you move it from off - on - off and this will relieve pressure on the switch to the underside of the case which reduces the "snap" to off or on.

I don't think they were manufactured with any, but maybe a tiny bit of lubricant on the plastic applied as you mention may reduce the drag between the switch and the underside of the case top, but I'd be careful about too much.

Not sure about which type of lubricant though, something that doesn't hurt plastic and won't dribble onto the circuit board underneath.

Other than that, it might just need a clean up.

cheers

Tony