I've read some topics on pens having good balance. Where exactly should it be along the pen's body, and does weight play a factor?

I have always thought of weight and balance as nearly a single issue. For me, I consider a pen well balanced if the weight of the pen falls just in front of, or right at, where I grip the pen.

just about.....there......where it just feels right

I have been wondering about this as well.

For me, it is balanced if the pen just lays in your hand, in a natural writing position without your having to hold it there with your fingers.

This is a very personal and subjective quality in a pen. If you want to find out where some expert pen people thought the ideal balance should be, try a Sheaffer "Balance" pen from the '30s or '40s. The one I have balances near the center when the pen is unposted. Posted, it is very slightly top-heavy. My hand is not educated enough to choose one over the other.

I don't happen to like pens that are either nib-heavy or top-heavy. I think a nib-heavy pen does not lie well in my hand; the top wants to wander around on its own. I tend to fight with a top-heavy pen; it tries to pull the nib off the paper all the time and I tend to grip it too hard to prevent that from happening.

You have to write with many different pens to find your own preference.

Paddler

I agree that it should be such that it lays easily in your hand so you do not have to actually hold it in position and your effort is concentrated solely on shaping your letters. This means that the balance should be somewhere near the middle of the pen so the center of balance rests on the spot of your hand where the pen naturally lays which for most people is the crook of where your thumb and forefinger come together. With equal weight above and below this resting place on your hand the pen can be effortlessly rotated all around making your writing smooth, flowing, and fast which is one of the main advantages in using a fountain pen instead of something like a ballpoint or rollerball where you have to apply pressure to make it write.

I consider my pen in 'perfect balance' if I can hold it as I would when I write, raise my forefinger off the pen and the nib rests directly above the paper without touching it. Most of my pens are in that perfect balance while unposted, but when posted the nib will lift away from the paper a considerable amount. Therefore if I use my pen posted, I must use more effort to write whereas if used unposted the pens seem to write by themselves.

That's my take on balance.

There are some physics involved here. Any pen is balanced when held vertically, but as the angle moves away from the vertical, a torque is felt by your hand.

To make matters more interesting, the distribution of mass along the length of the pen is often not constant since the nib and posted cap areas are often denser than the center of a pen. An unposted cap of course does not contribute, which is why many prefer not to post. If a pen is too short, on the other hand, it may not provide enough control.

Thinking about this a bit, I'm not sure if my thought about control is true though. Take a "51" -- do you really have more control with it posted than unposted? One's hand outweighs the pen, after all. Personally I feel like I do have more control with a "51" when it's posted.

Maybe in order for a pen to feel good in the hand, the torque felt in the hand must be low but not zero. A pen that is 7 inches long when posted is just not going to be comfortable.

Getting back to pen angle, I think that those who hold the pen at a higher angle should, in general, find a greater number of pens well balanced than those who hold the pen at a lower angle.

Stephen

The weight, I think, should be located at the center point of the pen in hand, or below it (toward the nib). If the weight is allowed up above the center point as you hold it, it begins to exert leverage against your movements as you use it. If you, for example, put a heavy weight on the top of the pen as you write with it you will get a feel for the extreme version of what I mean- you will actually feel the weight trying to direct the pen as you move it. It will feel as if an invisible hand is directing the pen while you try to write with it- not good. With the weight lower you get a little more direct-control type feel. If you allow it to get too heavy at the nib you get the feeling of "trying to move a rock" with your fingers. This, I think, is controlled by keep the pen light in weight overall. But on the subject of pure balance- you want to keep the center of gravity low on the pen as your write (toward the nib) if possible, I think.

I agree that the original Sheaffer Balance did this very nicely- and is still not bad in feel even when posted. Unposted, I've found the standard and slim sizes to be very light weight and not top heavy at all.