Overfeeds are devices that rest on top of the nib, and are designed to store additional ink between the nib and overfeed and feed that ink to the tip of the flexible nib when it lifts off the underfeed. That's a mouthful, but it sums up the performance of overfeeds.
Overfeeds were used during the golden age of fountain pens, but you hardly see any today.
Most historical overfeeds are fixed permanently into the pen. Ours are removable. They are designed in the same shape as the nib they support, for example, our most popular overfeed is roughly the same shape as the Zebra Manga G and Brause Rose nibs. These are both popular flexible nibs whose performance is improved with an overfeed.
You can remove our overfeeds for several reasons. First, you will want to clean the front of the pen from time to time, and the best way to do that is remove everything there. You also might want to replace an overfeed that has bent too far or sprung. More on this below.
This article is a companion to About overfeeds.
This is a picture of our overfeed from above and below.
The shape is designed to fit over a Zebra Manga G nib as well as nibs of a similar size and shape, such as the Brause Rose nib and our Sketch and Music nibs.
The overfeed is one part of three that fit into the front of the pen, as shown below.
The underfeed is at the top, the nib is in the middle, and the overfeed is at the bottom.
To assemble these parts, begin by bending the tip of the overfeed as shown below.
Don't bend it all the way down, but don't be too concerned about the precise angle. This will adjust when you insert it into the pen. Next take the nib and place it on top of the underfeed.
Now take the overfeed and put it on top of the nib, then push both the nib and the overfeed to the back of the nib.
Don't push them over the nipple that extends from the end of the underfeed. The nipple will seal the front of the pen. Next push the nib and feed assembly into the front of the pen.
The fit should be tight but not bind. You can wiggle the unit so its seats completely in the front of the pen. You can tell when the nipple of the underfeeds seats correctly.
You can tell the unit is seated completely and positioned correctly when it looks like that shown above. The shoulder of the overfeed is tucked inside the pen, the overfeed is seated squarely on top of the nib, and the tip of the overfeed is positioned a few millimeters back from the tip of the nib.
You can also assemble the unit piece by piece. First, press the underfeed into the pen and make sure it is seated correctly. It should remain fixed in place. Next slide the nib in over the feed as shown below.
Press the nib in all the way and make sure the base of the nib s seated in the back of the pen. If you find the front edge or point of the nib too sharp to press, point the nib into soft but firm material, such as firm rubber padding, and put pressure on the back of the pen to press the nib in.
The last step is to slide the overfeed in over the nib. When you get good at the process, you can press in the nib and overfeed together as a single unit. This can be difficult if the overfeed is bent too far, and the tip keeps sliding off the nib to one side or the other.
You aren't yet ready to start drawing. You have to check your work. Remember when you bent the overfeed at the beginning of this process? You must now check to make sure the curvature remains. Most likely, the angle of the bent overfeed will have flattened a bit after all the handling and pressing you've done. This is expected. You have to make sure, however, that the overfeed does lift off the top of the nib slightly, as shown below.
Notice the shadow cast by the overfeed on the top of the nib. This indicates the space you want to maintain between overfeed and nib. The space permits the easier flow of air back into the pen, to replace the ink that is flowing out. The space between the nib and overfeed might disappear over time and use, as the nib bends backwards. When this happens, slide the overfeed out, bend the tip down a bit, then slide the overfeed back into the pen.
In the end, this is the result you want to achieve.
Both lines were drawn with the same nib. The hairline on the right was drawn with a light hand that did not flex the nib. The thicker line on the left along with the variation in thickness was created by flexing the nib with hand pressure and bringing the overfeed into play.