When you use a fountain pen, the nib seems like the most important part of the pen, but there are several parts inside a fountain pen that are just as important. One of these parts is call the ink feed located in the pen under the nib.The feed controls the flow of ink from the ink reservoir inside the pen to the tip of the nib by constraining two controlling the flow of air back into the pen to compensate for the lost ink. Plug up the air flow and you'll never get any ink out of the pen. Open up the air flow, and ink will flow out uncontrollably. The feed is really an "ink/air feed" controlling both the flow of ink out of the pen and the flow of air into the pen in a balanced fashion. That's a lot to expect from a solid piece that doesn't adjust or move. 

We provide a variety of feeds for our pens based on the way they control the air/ink flow in the pen. The feed has to be matched closely to the nib, the pen, and the flow you desire. The interface of nib to feed must be precise so ink is transferred from the feed to the nib without leaking. 

Feed flow rates

We provide two feeds with the following flow rates to support the nibs we sell.  

• Thick flow or F4 feeds let you work with traditional India ink that contain carbon dust and shellac or gum Arabic, all of which thicken the ink. You can also use standard acrylic paints with this feed. 
• Standard flow or F3 feeds let you work with the widest range of inks, principally dye based ink that are colorful and often permanent, but aren't as thick as India ink. 

We plan to expand the list in early 2026 when we provide F2 feeds for water colors and very thin ink like walnut ink. 

F3 and F4 feed feeds serve most of our customers best - artists who draw and write using India inks and acrylic paints. We have been providing the F4 ink feeds for years. Traditional artists familiar with genuine India ink and thick acrylic paint prefer these feeds, but newer artists prefer dye-based inks that are thinner so they flow in standard fountain pens but just as colorful and lightfast. 

Something to keep in mind

Ink flow in fountain pens is not an exact science. Feeds control the flow of ink and paint based on the viscosity or "thickness" of the ink/paint. Other factors contribute to ink flow, including how quickly you draw or write, the absorption of the paper you're drawing or writing on, the warmth of your hand, the ambient air pressure, even the electrostatic charge and potentials of the inside surfaces of the pen, which can vary.