This should explain a great deal to the curious.
http://www.laserwelding.co.nz/The filler rod can be smaller than a human hair, laying down beads beneath a microscope that look like miniature ears of corn.
After the material is built up on the piece, it is dressed down to required dimension. The great break through is the small heat affected zone.
You still pay for the hand polishing and fitting. But no disassembly problems.
All that said, Unless the pin can be removed, only certain parts of the pin could be welded. Which as has been beat to death, is really ok, as not 100% of the pin is used as a bearing surface.
If you google Micro Laser welding, you will find a shop in PA that might be a source if contacted. You will also find all the technical drawings that show how the light is focused, how the power is modulated to heat only very tiny places, and how weld beads smaller than you can imagine are layed. Fascinating stuff.
Just understand, it isn't magic. It's bench time. Fabulous benchtime.
A piece of equipment like that probably has higher value density targets than cross pins on Crescents. But hey, they sell time. It's a declining asset.
