It may sound a bit OCD, but weigh and balance the arrows again and record the results. This is where you find out how even your sanding was when you brought the shafts down to the same weight...

If all has gone well, the balance point should be within 0.5cm of the 60% mark, and the weight within 2 grains or so.

If you're pushing for perfection, you can go back to the sandpaper and smooth the weights back to a match, then balance again. This will also take off any pencil marks on the shafts if you're planning on a varnish finish - with the nocks on you won't need them again. Be careful not to end up sanding for weight, then sanding for balance, then finding the weight's gone again ..

Nice. This set balances to 28.0 - 28.5cm and a weight spread of 4 grains. I may try and nudge the weights all down to 422 grains before moving on.

21st March: Ten minutes work with the sandpaper, all down to 422 grains. Slight improvement in average balance point from 28.145cm to 28.06cm. Smug mode engaged.