This is a Technical Bezel Filing Demo showing How to File Your Bezel Before Soldering.
It is very important to pay attention to the “contact point” or the soldering joint you are attempting to solder. Spend EXTRA time making sure the 2 ends to be joined are as flush as possible. When I say “flush” I mean the 2 ends need to be as closely matched up as you can get them. Use your magnifying visors or an eye loupe to ensure they are evenly matched and flush.
The 2 ends to be soldered need to match well and have no gaps which will take more solder to fill in the area. Solder “will” fill in gapped areas, but it will be a weak union, filled with pits, and when you go to finish the piece, it will have a darker color and have pits that will be unattractive. This solder joint will likely break easily if it is on a high use area, or a stone setting.
* With a little more time spent preparing the solder joint, these defects can easily be avoided, and you will have a much higher chance of soldering successfully.