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Tightening tab backs


#1

Anyone have a tried and true method for tightening “tab” backs for
coin = bezels without gouging the coin and without it spinning?
Prefer not to = use glue. Thanks in advance,

Bob Staley
B.Staley, Goldsmiths
Precision Laser Welding
@B_Staley_Goldsmiths


#2
    Anyone have a tried and true method for tightening "tab" backs
for coin  bezels without gouging the coin and without it spinning?
Prefer not to  use glue. Thanks in advance, 

Bob, Sometimes it helps if you use a fine sawblade and make slight
cuts on each side of the tabs. The cuts should be just enough to
allow you to bend the tab low enough to the coin. Pre-bend the tabs a
little by clamping down low on the tabs. Then put a stiff piece of
leather to the front of the bezel so that one jaw rests on leather and
the other is on the tab. The plier is in line with the tab. Firmly
press down and forward to almost set the tab. Do the opposing tab
and
then the others in an order you would use to bolt a wheel back onto
your car. Once all the tabs are almost set, go back and finish
setting them down tight, once again following a cross tightening
sequence.

I use a pair of modified loop closing pliers. These pliers have a big
clearance behind the active part of the jaws which are ground down to
just remove the loop indentations. The remaining portion of the
active part of the plier tips are shaped. These pliers provide a lot
of visual access and the relatively small working surfaces of the
plier jaws provide controlled, concentrated pressure. To make these
pliers, I used German-made loop closing pliers. The economy Pakistani
pliers don’t have enough tip left after you grind off the loop
indentations. I guess you could solder metal into the indentations of
the Pakistani pliers, finish the surfaces flat and then grind the
plier tips to get nice, small working tips.

I used this approach to set 24K gold coins in rings and pendants of a
production line. If this isn’t clear enough, email me offline.

HTH,
Donna Shimazu