Relatively inexpensive - you can custome design a keypad and have them made, just like you get PCBs made. What an idea for a control panel - and not just the switches, they can embed LEDs in them! The main cost is the tooling, but that's a one time charge, they actual keypads are pretty cheap. So the idea would be to deisng a puzzle piece sort of thing and have dozens made, then fit them together as needed. It doesn;t make a whole lot of senst to say draw up your whole ayrd and make one big membrane keypad - that would cost a fortune.
This video from Dave Jones talks about it and mentions one such manufacturer that he has used.
https://www.youtube.com/watch?v=H8XBBfvsPj0
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
yep .. as you say most of the cost is in the tooling, the first design ..
i use allpcb for what i need, flexible is a bit more than rigid, but not much ..
most of the time i just use off the shelf matrix's with a pretty simple membrane overlay, nothing special, and cheap on ebay .. especially numeric keypads .. and in small quantities, less than a dozen each