Looking for opinions on rubber keypad vs rubber + membrane

[priority1c]

I am in a little argument over rubber keypad repair with an unreasonable person. I am looking for other opinions.

We currently repair a certain keypad that was manufactured with an obvious problem. The rubber pills are 3mm diameter and the circuit board contacts are a star inside a circle that is 6mm diameter so the conductive pill barely touches the outer ring. Picture

Any amount of oil or build-up will effect the buttons almost immediately and quickly make them impossible to use. As we know, most rubber keypads secrete oil (Source)

We use a membrane insert between the original rubber keypad and the circuit board. Our membrane has 7mm conductive contact area, blocks the oil the keypad produces and prevents the carbon pill from breaking down leaving the black residue behind.

From looking through keypad manufacturer's web sites, this seems to be the preferred method or at least an improvement over a rubber keypad alone.

Any other opinions out there?
Can anyone think of potential problems with this method? We have tested this extensively with countless machine controlled keypresses and even froze and heated the repair several times but it is nice to get input from others.
Thank You

 

[MacGyverS2000]

Won't the insert secrete the same oils as the original membrane?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[priority1c]

The original is a rubber keypad not a membrane. The membrane insert does not have oils and is made with plastic that will not allow the oils to penetrate.

 

[BobM3]

Check out GGI International's "Pushgate" switches. I've been happy so far with their durability.

 

[priority1bc2]

The GGI Pushgate switches look very interesting but they will not work for my project. We are not designing this from scratch and the circuit board cannot be changed at this point.

We already have a solution that is working perfectly and I am not looking for another one. I would just like other's opinions on the rubber keypad & membrane combination. If anyone knows of anything that could go wrong etc...

Thanks