>Not necessarily. Some alloys are designed to be self-healing. Yes, I've heard that too. Which alloys? 73, Dick, WC1M -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@contesting.com Problems: owner-towertalk@contesting.com Search: http://www.contesting.com/km9p/search