Pete,
Those magnets are a claimed 3kg strength. No one has come forward with any equation to measure how much two opposed would hold (obviously minus the small lateral friction!). Do you think a pair of those is anywhere near holding up 6kg?
I have moved off BBs on oak to pure ebony, temporarily (maybe).
Ian
What does the ebony sound like ...?
I've no idea as to the weight two magnets will hold up .....
the two rings of magnets was not as good as the original set up.
I've now got my 20mm one and they are strong !
I shall have a play and report back !
Just a quick correction for Uncle Ants:-
The Clearaudio Ceramic Magnetic Bearing, floats the platter, there is no ball bearing at the top of the spindle shaft, the whole weight of the platter is held by the magnet. I have just fitted one to my turntable.