Fingertip Tight

If you've ever canned anything, you're familiar with the term "fingertip tight."  For those of you who are not canners, jars are sealed with a 2 piece system consisting of a lid and a band.

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Band on the left, lid on the right.

Virtually every canning recipe includes the instruction to tighten bands fingertip tight.  If you tighten the bands too tight, the jars won't seal properly.  If you don't tighten enough, the jars won't seal properly.  It's a classic case of not too tight, not too loose, but just right.  But how to find that elusive just right middle ground?

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I have been canning now for at least 6 years, and I still have no idea what the heck fingertip tight means.

Well ... I thought I knew what it meant ...

I rarely have trouble with my water bath seals (in fact, I can't remember any of my water bath canned jars not sealing.  Ever)--they're a bit more forgiving, but I've had inconsistent results with the pressure canner.  And who knows if my bands are too tight or too loose?  Not me!

So I did a little research and learned ... no one else seems to know, either.  Or, rather, everyone knows, and everyone thinks it means something a little different.

*Sigh*

The most useful answer I found was from Carolina Canning:

A practical way to determine if the lid is fingertip tight is to place the band on the jar, turn it just until you feel resistance, then turn the band one-quarter turn more. 

So, I guess that's what I'll do.