(This page published April 19, 2021)
What is the cause and what can be done to a new fountain pen that tends to start skipping after a few minutes of writing? The pen in question is from a USA manufacturer of relatively expensive pens.
The problem can have any of several causes, and you may be able to fix it easily.
First, new converters frequently are left with some of the manufacturer’s mold release compound on their interior surfaces. This makes the converter hold the ink at one end, usually the wrong one, because the wetting agent in the ink can’t overcome the “oily” effect of the mold release compound, and the ink won’t flow easily to the other end of the converter. Flushing a converter with a good pen flush (or a 1:10 solution of clear household ammonia in water) — clean it out thoroughly afterward — may remove the mold release compound so that the ink can flow along the converter wall. Do not use harsh household cleaners such as Formula 409 for this purpose; these substances can damage pens!
There may be some amount of mold release compound on the feed, or even a trace of oil from someone’s fingers remaining on the underside of the nib. Flushing to clean these surfaces may help.
Flossing the feed channels and the nib slit with a piece of 0.002" (0.05 mm) brass shim stock might also help, as occasionally there’s a tiny nit of manufacturing detritus stuck in there. You have to pull the nib and feed to get at the feed channels, but the nib slit is exposed in most pens. The image here shows me flossing the Christmas Tree feed from a Parker Duofold, but the technique is the same. (Note, however, that you can't easily get at the channels in some pens’ feeds; the Pilot Vanishing Point, for example, requires a special wrench to take it apart.)
You can try a different ink, one that flows more readily. Private Reserve Tanzanite used to be famed as the “Ex-Lax” of inks; some pens that flowed terribly with any other ink would be just fine with Tanzanite. Aas of this writing, however, this is no longer true because Yafa, the current holder of the Private Reserve name, does not have access to the formulas developed by Terry Johnson, who founded Private Reserve.
When you’ve exhausted all the things you can do, you have a choice. The pen is most likely suffering from a phenomenon called feed starvation, in which the pen does not admit air properly to offset the depletion of the ink supply. A partial vacuum in the cartridge or converter prevents the ink from flowing. The solution to this problem, which affects plastic feeds more than hard rubber ones but is not unique to plastic, is out of your hands unless you’re experienced in dealing with it. You can return the pen to the maker for refund or repair, or you can send the pen for modification by an independent repairer who specializes in making balky pens write.
Is there a safe way to reduce the ink flow on a nib that otherwise works fine?
The easiest and safest way is to choose an ink that flows less freely. But that’s usually not a desirable option.
Ink flow can be reduced by restricting the channels in the feed. This is a task best left to experts.
Examine the nib under magnification. How wide is the slit at the tip? As wide as a Los Angeles freeway? A slit that wide will act as a fire hose. (A slit that is fully closed, on the other hand, will behave like a clamp, restricting the flow.) A properly-formed slit is usually tapered slightly from breather hole to tip, as shown to the left. Narrowing the slit is best done by pulling the nib and gently bending first one tine, then the other, downward. The natural curve of the nib will cause the tine tips to move closer together. Permit me to reiterate the word “gently” in these instructions; it's always easy to bend a little more, but it can be terribly difficult to unbend a nib that you’ve pushed too far. Do be careful, while you do this, to align the tines properly as you go; push too hard on one and not hard enough on the other, and your nib will be very scratchy.
If you aren’t able to pull the nib, you can do the same thing as follows: Hold the pen horizontally, uncapped, with the nib on top of the feed, not underneath, and pointing away from you. Place the index finger of your right hand under the feed to brace it. Place your right thumb on top of the right tine right at the end of the feed, and push downward gently until the tip clicks as it passes under the left tine. (Don’t push down farther out toward the tip, or you will bend the nib right where it passes over the end of the feed.) Release, and repeat with the left hand and the left tine. Check for alignment, and see whether the slit is narrower, but without the tines touching. Test. If you went too far, turn the pen over so that the nib is downward. Brace the nib with an index finger, place the thumbnail of the opposite hand crosswise on the underside of one tine right at the end of the feed, and push downward just a little, in essence moving the nib away from the feed. Repeat with the other tine.
While you were examining the nib and feed under magnification, did you take note of whether the nib lies nicely along the feed? If there’s a gap that isn’t big enough to break the capillary flow, that gap is also allowing lots of ink down to the nib tip. Bending the tines down will close this gap and reduce the flow. If the flow is too lean, bend back upward with extreme care until you’ve opened the nib just enough.
A better way to close the gap between nib and feed, if you have a pen with a hard rubber feed, may be to heat the feed gently, getting the whole feed warm. There will come a point at which it will soften; stroke your finger along the under side of it to make it conform to the nib, and then, still holding it in place, allow the feed to cool in its new shape. Go slowly; as with nib bending, it’s easier to go further than to undo too much. This method is especially appropriate for pens whose nib slits are properly tapered. Do not attempt to re-set a plastic feed in this way! You will almost certainly destroy the feed.
If you’ve read this far and are now quaking in your boots, fear not. The modifications I describe are all well within the capability of any competent repairer, and the cost for them should be relatively low.
The information in this article is as accurate as possible, but you should not take it as absolutely authoritative or complete. If you have additions or corrections to this page, please consider sharing them with us to improve the accuracy of our information.