We don't use the linseed oil anymore. After having some old instruments visit us for rework, it tends to remain tacky even years later. At the endgrain, little beads of the stuff formed, making a rough surface. This was easy enough to dissolve with more oil without disturbing the patina, but the slight tack to the touch is a bit annoying.
We are using a polymerized oil finish now. I don't know the brand off the top of my head, but on
this old page you can see the first coat of oil being applied.