My recollection on balancing rods is that it's a two phase activity.
First you make the rods pretty much weigh all the same.  Then you start
balancing them.  Something like finding a balance point for each rod,
and measuring how far it is from the inner-most point on one of
the rod end bores.  These should all be at exactly the same distance.
If one varies, some material is removed at an end to bring it into
balance.  Once this process is done they're all balanced but their
weights vary.  I'm not sure how that's dealt with.  I know my balanced
rods show signs of material removed at the ends; I can't remember seeing
signs of material removed on the area between the end bores.

> On Thu, 14 May 1998 14:34:59 -0700 David Bayer <bayer@SYBASE.COM> writes:
> >        Ok, I almost give up, does anyone have any tricks for wieghing
> >the
> >ends of the rods? I am trying to do this a la the discussion at the
> >end of the
> >Muir book for balancing rods which states having the all bottoms ends
> >balanced
> >and all top ends balanced is more important than having the overall
> >rod
> >balanced. The trouble is, I cannot get an accurate reading off the
> >triple
> >beam balance I am using to do this (the weight of the end changes as
> >the scale
> >moves up and down ;) ). Is there any easy way of correting this that I
> >am
> >missing (short of buying an expensive ditigal scale which can handle
> >750
> >grams but doesn't move at all when you put weight on it)? I was pretty
> >good
> >with the pistons - they are all within .2 grams of each other - so I
> >would
> >like to get the rods as close as possible too. Any suggestions on this
> >topic are much appreciated...
> >
> >dave