Simple momentary switch idea: Will this work?

I'm somewhat new to the hardware side of electronics, and need to build something with ALOT of momentary switches using the Arduino. I'm poor enough that even buying a bunch of momentary switches is going to make a nasty dent in my wallet. However, I've seen people use nails and other bits of metal as crude electronic interfaces, and I want to know whether this will work.

--- My Idea ---

Take something conductive. Like a nail. Connect (low, preferably) voltage to it, and then add a pullup resister going from the nail to an I/O pin. When nothing is touching the nail, the I/O pin should be high because the electricity has nowhere to go but through the resistor, but when my finger presses the nail, the electricity follows the path of least resistance down my body into the ground. The I/O pin goes low, signifying a touch.


I figure if all I have to buy is an LED driver, some LEDs, and some multiplexing chips, I can make something similar to a Monome for about 50$ using some spare acrylic/plywood and some metal contacts. But that only really works assuming that my idea isn't completely stupid and won't result in a dead Arduino.

Other benefits are that the construction will be infinitely easier, neater, and more durable this way. Metal contacts won't get nasty, or stuck, or break. It's going to be part of my live performance rig, so this is really ideal.

P.S. I know about capacitive sensing, but it's going to be slow for over 64 contacts. I would prefer to do things this way.

I don't know if you'd get enough current through your body to register a LOW on the Arduino (plus, it would vary from person to person).

Are you sure you can't afford momentary switches?

Digikey has them for ~ 10 cents each (if you buy 64).

That comes out to a little under 7 bucks. Not too bad.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=CKN9082-ND

I would expect static or other unforeseen contact to damage the digital IO. I just bought 100 micro switches from here http://www.virtualvillage.com/switches-and-relays.

I'm poor enough that even buying a bunch of momentary switches is going to make a nasty dent in my wallet. However, I've seen people use nails and other bits of metal as crude electronic interfaces, and I want to know whether this will work.

Well, any reason you can't find a nail and do some testing?

you guys are lucky, when I was 16 you still had to call in or write in to get people to mail you datasheets heh

you guys are lucky, when I was 16 you still had to call in or write in to get people to mail you datasheets heh

:O Seriously?

I guess we're a little spoiled by this new-fangled "Inter-Nets" thing..

I have to get some money in the bank and order my Arduino first. Metal contacts would greatly simplify the build. Prolly just bite the bullet and buy some switches though.

Fax Baby... You used to call support lines and request they send you a fax with the datasheet you wanted... LOL