Lenses are shaped and ground to perfection by polishing when manufactured,. not with some Calcium Lime and Rust remover. There are some things in this process that you may not be able to do by yourself. I would suggest trying tirediron's suggestions and contact a glasses store to get contact information on a lens manufacturer that can assist or Hasselblad themselves. They may be able to direct you to whomever they use to manufacture the glass for their lenses. You have done outstanding work so far and it would be a shame to ruin the glass itself. Am excited to see how it all comes out when you have it finished.
The CLR suggestion was not about polishing but that the scratches which are a byproduct of the fungus may only have etched into the coating layer. The CLR would remove the coating layer and take the scratches with it leaving the raw element unscathed.
The Hasselblad lenses of this era (and I think all the V series) were made by Zeiss (who I may try and contact about this). Unfortunately this particular lens was not really produced in any kind of substantial numbers and most are still in pretty decent shape due to little use so donor lenses are rare in their own right.
On any note I went to the hardware store at lunch to pick up some CLR and see if I could get the coating off.
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Unfortunately it appears there is no coating on this element (anymore at least) and the scratches are indeed in the glass. At this point any kind of polishing or grinding is going to change the characteristics of the lens anyway since it will require removal of glass and thus change the element thickness. I am tackling this a few different ways.
1. Hunt for a replacement element from Zeiss or Hasselblad
2. Talk to an optics shop and see if it can be saved.
3. Try and find the specifications for that element and see if an optics maker can cut one
4. The the specs (if I can get them) build a grinding jig and see if the element can be salvaged.
While lens grinding is not really an at home task the point of this project was to attempt DIY solutions to things like this so I am also going to try and read up on what I may be able to do. The chances the grinding is successful, slim.
Regards
Dave