The approach both pens take to balancing the barrel, is different. The Nakaya pen came with a little stick, and a pouch five little weights.
These weights can be inserted in the barrel by removing the cap at the end of the barrel, and then screwing them inside the barrel. The barrel has thread inside, just like the cap. The picture below shows the barrel that is open, with one weight inserted.
On the other hand, the Conway Stewart pen has an integrated balance adjustment mechanism. The balance is adjusted by turning the blind cap. A nice touch is that the blind cap fits seamlessly on the barrel, see the picture below. No attempt has been made to have the engavring continue on the cap, so there is no discontinuity when the cap is turned (this is different with the blind cap of the Visconti Wall Street that I have).
Inside the barrel is a weight and a spring, and by turning the blind cap, one can adjust the position of the weight, and thereby the balance. The spring is just visible in the picture below.
Then the question is, does it work? Do these mechanisms adjust the balance to a noticebale degree? I have tried to see whether the center of gravity really shifted by putting all weight near the section first, and then inserting three rings (Nakaya) or putting all weight near the blind cap second. The results are shown in two stitched pictures.
Clearly, these mechanisms adjust the balance of the pen. As the Nakaya pen is lighter, I think their mechnism with weights is somewhat more effective. On the other hand, one needs additional things (the little stick, and additional weights) to adjust the balance. An advantage of the Conway Stewart approach is that it does not require any additional parts. I assume Conway Stewart will include this mechanism in other models in the future.
Edited by MYU, 29 November 2008 - 17:11.