Lewm,
My dear friend and comrade Nandric and I have had running arguments in regards to my love for the JVC 7045. He also has one that he hasn't found time to mount. He's in love with his FR-64. It was actually him that convinced me that perhaps I should at least try a heavier arm with my FR's.
I must admit, I was also surprised at just how good the JVC is. In many regards, it is quite similar to the Lustre. Both have VTF adjustment on the fly. Both, removal head shells. Both have exceptional bearings. The only short coming that they both have is lack of azimuth adjustment. I solved that problem by the exclusive use of the Sumiko/Jelco head shells. LP/tunes also carries the same head shell but calls it the Supreme.
In regards to the use of magnetics for the VTF on the Lustre. I still prefer the old fashion method. Balance the arm, then move the counterweights for VTF using a digital scale for verification. I've been doing it that way for damn near 50 years so I am too old to be changing! (grin) I like the magnetic concept but 'blind trust comes into play with that design and considering the arms age, well, I just don't trust 'trust'! (grin)
As far as effective mass? I wish I knew. I did the typical search but found nothing definitive. Only speculation. Considering how it performed in regards to my 'high compliance/low compliance cartridges, I tend to believe it is on the lighter side. The arm assembly has stainless steel parts, but the arm tube is of an aluminum mix. Mix of 'what' would be an interesting discovery. This would explain the lack of corrosion that you and I expected to see. I also though it was stainless but discovered this aluminum mix statement somewhere in regards to its arm tube.
My TT-81 came without arm. I had a spare Graham 2.2 and had thought about mounting it on the TT-81 but what I really wanted was a arm with a removable head shell. The Graham has removal arm wands. Those wands were $800 a piece new, $400 used when you could find someone willing to sell one. Thanks to the M/M thread, I have more cartridges than I care to admit and to place each of them in their own arm wand would of forced me to sell my house and give the profits to Bob Graham. (grin)
I did a search to determine what others were using with that table and to see what was recommended by JVC. That 7045 was/is JVC's top arm and considering it was 'the' arm during the legendary production run of both the TT-81 and the TT-101, I went looking for one. Just so happens that 'Foxtan' had a good one available so I bought it. I now consider that an even better decision than the actual purchase of the TT-81.
Lewm, you are wondering how much do I really like the JVC 7045. Let me put it to you this way. And I am being quite honest when I state this. I am considering selling my Graham 2.2 and mounting the JVC 7045 in its place on the VPI Aries table. Those two tables (the VPI Aries and the JVC TT-81) would have excellent arms on each of them with removable head shells. This would allow the mounting of low compliant cartridges to high complaint cartridges when ever I wanted. No arm changing required. No 'wondering' if a higher mass or lower mass arm would be a better match. Performance wise, I would loose nothing. All three of the mentioned arms are 5 star arms in my opinion. But I gain in versatility.
The biggest problem in all of this is the selling of the Graham. to do this is to me like selling my beloved dog to a stranger! It is going to be a tough thing to do. I'm the original owner and have had that arm for many years. The selling of the dog I couldn't do. But selling the Graham? I definitely leaning that way!
Regards,