I actually don't see the big deal on adjusting product balance weights working-time wise. Not a big deal, just a few screws and some sealant when done.
Btw, the manual does stipulate something:
BHT-412-MM-2 Ch 18 Pg. 33.
Once a main rotor has been product-balanced, it
should not require additional product balancing until a
blade is replaced, or an existing blade is refinished,
repaired, or otherwise altered. Therefore, when
trimming a previously worked main rotor, use pitch link
adjustments and/or hub balance weight adjustments to
correct balance.
Thnx for the other advises. I just wrote them on my book so I'll follow them the next time I balance a 412 (hopefully next month).
