First, let me say that this post will not tell a heroic story of me nursing a sixty year old pen back to its former glory. Life is not always like that. Unfortunately I have not yet been able to get the pen working again. But it has not been a complete disaster. The pen is an interesting one and I think the story is still worth telling.

I had largely got out of the habit of searching eBay for vintage pens, as I find it very addictive and never-ending. However, on a recent bit of idle scrolling, I spotted this Osmia Faber Castell pen, at a modest price of £21.50. The seller provided only three photographs. The ‘Additional Description’ just referred back to the photographs and invited questions if a buyer had any doubts. I sent a few questions such as whether the piston was working and whether the pen filled and was usable or needed repair. After a gentle reminder, the seller replied that he did not have the knowledge or skill to answer my questions. I decided to take a chance and buy it anyway, figuring that it would either be usable or an interesting repair project.

The pen arrived a couple of days later. The pen dates from a time when Faber-Castell was in the process of acquiring the Osmia pen company, which was finalised in the 1960’s. I found the pen interesting for several reasons. I had not come across Osmia pens before and knew nothing of the firm’s history or its range of pens. This was a story waiting to be discovered. The pen itself looked appealing – with a black cap and barrel, rounded ends, a contrasting green grip section and an amber coloured ink window (with a green filled indentation in the middle). The pen is a piston filler. The piston knob is accessed by removing a blind cap.

The nib has an imprint FABER OSMIA and a figure 3 inside Osmia’s diamond shape logo. The nib is not gold but has gold coloured plating and is set on a feed which I think is ebonite. The nib and feed appeared to be in good condition.

The cap has an imprint FABER CASTELL and what I presume to be a serial number, AF0815. The barrel also has an imprint of this same serial number, as well as a model number, of 53SM just before the blind cap. It is rather nice to have the serial number on both cap and barrel, to know that they are an original pair.

On arrival the piston knob would not turn. I stood the pen in a jar of water overnight, to soak the nib and feed with a view to extracting them. When I returned, I found that water had reached the reservoir. Whether this was by capillary action up through the nib and feed, or else by a leak in the pen, I am not sure. However it was nice to see liquid sloshing around in the pen, even if it was not ink! I tried to let the water moisten the piston to allow me to raise and lower it, but it would not budge. I then put the pen to soak again, but this time horizontal and with the entire barrel immersed.

After a night’s soak, I tried pulling the nib and feed out. To my delight and relief, they came out very easily at the first attempt. I could then introduce some silicone grease, on the tip of a tooth pick, onto the piston head and the inside walls of the ink reservoir.

I was later able to get the piston knob turning freely and I could watch the piston travel up and down. This seemed promising. Nothing was broken. But whilst the piston now moved up and down, it did so too easily and was not airtight. Consequently it would not pull a vacuum and could not draw ink up into the barrel. I surmised that a cork piston seal had perished. To repair the pen I would need to first remove the piston mechanism, replace the cork seal and then insert it back into the barrel. This sounded like a fun but satisfying challenge.

One new feature of this repair story for me, was that I made use of AI. I asked Chat GPT for information on the history of the Osmia pen company. An interesting response came back. The AI lady (I assume she is a lady!) was most enthusiastic about my purchase and I learned that Osmia nibs were very well regarded.

Unfortunately, I have not yet been able to remove the piston from the barrel. As well as soaking in water, I tried applying some gentle heat with a heat gun to soften the glue. Despite this I have not been able to unscrew and remove the piston mechanism. I am anxious not to force it and break it. Given the age of the pen it would be very easy to crack the piston shaft or the barrel if inappropriate force is used. I am not sure whether the the piston housing is even designed to unscrew, and if so, which way. With a vintage pen, there is also a risk that a repair may have been carried out in the past and some unsuitable glue used that does not readily loosen, and so it is wise to proceed with caution. As doctors say, ‘First do no harm.’

The good news however, is that I have been able to use and enjoy the lovely Osmia nib, by inserting it in a TWSBI Eco. Now, the nib is served by a fully working piston filler barrel and a fill of Pelikan 4001 Konigsblau, which seemed like a suitably German, school-friendly ink that it might have been used to.

And so all is not lost. I did not break the pen. The nib is writing and now enjoys a large capacity, demonstrator barrel and section. I am using the TWSBI’s own plastic feed. Care is needed when swapping nibs to ensure that there is enough headroom in the cap for the intended nib. The nib has settled well in the TWSBI and I enjoy using it. There is plenty of wear left in the nib. It is a firm nib but writes smoothly and with good flow and a medium width line, once the sweet spot is found.

I have not given up on the piston repair. If anyone has any advice on servicing a piston on this model, kindly let me know in the comments!