The Kaweco Sport fountain pen is brilliantly designed and reasonably priced. When it’s capped, it is compact enough to fit in any purse or pocket, and when it’s posted, it is the perfect size for writing. However, one downfall of the pen is that it can only be used with short standard cartridges, wasting the space of about 1/3 of the barrel. Also, it cannot be used with a converter so writers cannot use their favorite bottled inks with it. (UPDATE: The Monteverde Mini Converter will fit inside the Kaweco Sport fountain pen.) To resolve these issues I converted the Kaweco Sport fountain pen into an eyedropper fill system, where the barrel is used as the ink reservoir. To prevent ink leakage I used 100% silicone grease (petroleum free) to seal the threads. Hopefully, this explanation will help other writers maximize their Kaweco’s potential.
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Wow, that’s very interesting. I have a couple of Petit 1 and Preppy. I will find out if I can convert them into eyedropper.
As long as the body of the fountain pen does not have any holes in it, it can probably be converted into eyedropper fill. We have been able to successfully convert fountain pens into eyedropper fill simply by using a little bit of silicone grease on the threads each time the pen is refilled with ink.
Wow, thank you for the visual instructions. I have collected a ridiculous number of Kaweco Sport fountain pens and have thought about making one or two an eyedropper. This helps!
Brilliant! I love this website. I think it is my heaven on the internet.
Fountain Pen Friday
Just in time for Fountain Pen Friday, my helper tells me that someone came to this weblog looking for ‘fountain pens for archaeologists’.
Easy, I recommend an “eyedropper fountain pen” (any pen with no mech…
this opens up so many possibilities! the magic of modification…
Just wanted to throw out here, anyone wanting to try this, do yourself a favor and get the grease! The threads are quite tight, and the body length beyond them a good buffer area that fits tight… Twas fine at first with out sealing, But not tight enough! it took 3 days to leak far enough to get inky fingers, but without sealing, it does leak none the less.
suffice to say, I will be ordering some silicone grease shortly… 😉
G.
A #5 rubber O-ring (from the plumbing aisle in your local hardware store), touched with a small amount of silicone grease, works wonders. You’ll have to stretch it slightly to get it onto the pen, so put it on first and THEN add the silicone.
Has anyone tried Teflon tape instead of grease? That’s how I would seal something like this in the lab (or for plumbing purposes). Maybe the clearance inside the body isn’t enough, but it’s a thought.
Dave – we haven’t tried Teflon tape ourselves. If you or anyone else tries it and it works please let us know. Thanks!
I tried the Teflon tape experiment using a transparent Kaweco Sport rollerball. After about 2 hours of grading papers I have no leaks, but I can see the ink slowly migrating down the threads so I’m sure a leak will soon develop. The problem is the clearance inside the body is quite small; too small to adequately wrap the threads with enough Teflon tape to do the job. The small amount of tape I did manage to get on the threads just isn’t enough.
Hi Dave,
Thanks for sharing the results of your experiment! I’m not very skilled at using Teflon tape while doing plumbing so I’m not so sure I could even come close to using it on a pen. 🙂
i did this and it’s been a pain to carry. it’s exploding all inside the cap, but i think it might be the ink i’m using–noodler’s heart of darkness.
Noodler’s heart of darkness tends to have a fair bit of nib creep on my Pilot Metropolitan too. The pen that comes with the ink doesn’t have the issue. I think it’s an ink issue more than a pen issue.