The last thing anyone needs on landing/flying is for the collective to rise if the friction lock is `off`-think about it !
The collective friction `off` should hold the collective in that condition,fully up/down,or have a `tendency` to fall towards min pitch.Probably a friction `pull-off` of about 1-2 lbs; if it`s any lighter and you don`t have friction/hand on collective,in turbulence you will get a PIO on the collective which can damage the head very quickly.
Any collective friction applied should be `smooth` from fully up to fully down with no `lumpiness/unevenness`,and a smooth single twist ideally from fully `on` to `off`. Can`t recall actual figures,rather `personal criteria` applied to Wessex and S-K as MTP for 4Yrs and TP for 8. Isn`t there a `collective` balance spring in there somewhere ? Syc...