Subject: Automatic center punch?

From: [email-masked] (Theodore Henry Phares)
Date: 14 Aug 1995 12:42:52 GMT

Hi,

I'm relatively new to machining & metalworking & have a question
regarding a tool i've come across.

I believe it's called an 'automatic center punch' or something to that
effect.  The device consists of a hollow cylinder, one end with a
screw-on cap containing a large spring and the other holding a spring
loaded hardened tip.  There's also some other interesting workings
whose purpose appear to be to hold the spring loaded tip back against a
spring.

I'm guessing that I am supposed to be able to retract the tip and then
do something to "fire" it into whatever material I want to dimple (thus
eliminating the need for a mallet & making it an "automatic" punch).. 
So far, however, I haven't been able to get this or anything else
exciting to happen.  All it will do is lamely retract & extend the tip
whenever I push the unit against something hard...  

Is there some secret to this thing's operation, or does the one I have
not work?

thanks.

--
ted phares
   university of california, berkeley - mechanical engineering
      uc berkeley solar vehicle project
         http://www.csua.berkeley.edu/~tphares