I am going to attempt canning for the first time and have done a lot of research on methods, equiptment etc. I have several 'old style' jars with the glass lids and zinc rings that, apparently, are no longer recommended. I have new red seals and was looking forward to using these old jars. Here's 2 of them Does anyone here use these old jars? How do you know when they are sealed properly? (The new style containers with the metal lids make a pinging noise when they seal) HELP!