Dental floss may work during the fitting stage but I don’t believe
it will help you during subsequent repair, which is the context in
which I made my warning. But that’s only half of it. The other half
is, as Leonid mentions, possible stone breakage. With sturdy stones,
no problem most of the time I suppose. When you start setting more
fragile stones, like Todd’s opals, the risk can sometimes be
intolerable. Not even going into the hammering stage, just dropping
the stone in the bezel, if its too tight you may chip the girdle.
Then again the other other half (three halves, more for your money!)
is, with a tight fitting bezel, can you really be sure the stone is
fully seated on the bearing and not just squooshed between bezel
walls? So now you have the situation where the bezel is jammed
against the girdle and when you start setting you put even more
pressure on it, or at the last moment the stone rocks out of
Given the risks, I don’t see a positive to making press fit bezels.
Todd, I once had the daunting task of setting a scary opal in white
gold. I used 18K palladium white to make a bezel about 1mm thick,
cut a relief inside, and used a hammer handpiece. It helps to polish
the hell out of the inside of the bezel so that at least you don’t
have irregularities to deal with, the kind where you might have a
little jagged gap and be tempted to hammer just a wee bit more.
Sometimes that wee bit is a killer.