Enlarging lens schneider-kreuznach 5.6 105

Just found this at photo swap in Dortmund, want to use on Jobo LPL c7700, for mid format. Anyone have experience w this lens, info on how old or quality of prints. Thx Ron

I just got done doing an assessment and cleaning of all my enlarging lenses. It is a big deal, I confess this is probably only done twice a decade.
But the basics are first making sure all the lens element surfaces are clean. If the lens surfaces don't clean easily, then they are permanently damaged. I have never found any strong chemical or forceful cleaning that can help destroyed glass and or coating. I don't always throw those away, sometimes glass of two lenses can be combined. Also, re-coating is available, but for $1000, it is frequently less expensive to look for an undamaged lens instead.
If the lens surfaces are clean and clear, then make sure the aperture mechanism functions properly.
If the lens passes those two tests, then one needs to work on mounting the lens to the enlarger. This can be easy or difficult depending on the enlarger and lens; each case is unique.

This is an example. I had cleaned the lens on the left when I got it a few years ago. I used it quite a bit and it works fine. Just to make sure it is not getting worse in my storage area, I disassembled it again and re-cleaned it but it is still the same. So that is all permanent damage. It will never get better without re-coating. So, even though the lens still works fine, I wanted one with clean glass. The lens on the right is it's replacement. The problem is that one might have to buy a number of lenses off the internet to get a good one. I was lucky with that one.
Either way, I still keep both lenses. Maybe someday it will be worthwhile to re-coat the older Componon.