Sorry if I misuse terminology...
I'm a master of malapropisms, spoonerisms and any other grammar malformality.
I grew up in WV where they say "tar arn" for a tire tool and "far" for fire and things like "tarnation" are used regularly.
Try to listen to what I mean and not what I say... and I'll try to be more precise.
A propeller by comparison has just two such lines
If you assume a two blade prop. Like fan blades, they too can have three, four or even five blades (common on WWII fighters like the Sea Fury and later 'Stangs, to soak up all that HP! pardon whilst I drool) again, the complexity of balancing such props increases exponentially.
Draw two lines intersecting a two blade prop at the center of the hub, one verticle and perpendicular to the centerline of the blades, and one horizontal along said centerline. Call each quadrant A (top-left) B (top right) C (bottom left) and D (bottom right). First you balance the prop so that the A/C side is even with the B/D side. Then still you must balance to see if the A/B side differs from the C/D side as well.
With a magnetic balancer, I can acheive prop balance in excess of the two-stroke motor that it is attached too very regularly.
Ceiling fans are a whole different ballgame even with what I know about prop balancing!
[This message has been edited by sparky66wv (edited 07-17-2001).]