Why don't desk pens leak?

[TrotskiKazotski]

Generally I hear that fountain pens shouldn't be stored nib down, which makes sense, as it could cause ink to drip out of the front. But then I realised that desk fountain pens are meant to be stored like this, and you don't really hear about those leaking, and they shouldn't, but why don't they? do they have some sort of internal design that makes them retain ink better, or is it the fact that most of them have hooded nibs, or is it an overreaction and are fountain pens normally fine when stored that way in general? 

 

TLDR, desk pens are stored nib down, why don't they leak

[A Smug Dill]

1 hour ago, TrotskiKazotski said:

But then I realised that desk fountain pens are meant to be stored like this, and you don't really hear about those leaking,

 

There are few active users of desk (fountain) pens these days, and even fewer who are also actively discussing their pen use habits online. Then, among them, few would routinely inspect the cups (or caps, or sockets) in their desk pen holders for tiny splatters or flecks of ink, especially using a piece of tissue or cotton-tipped swab to be thorough about picking up any stray ink. Furthermore, desk pens in their dedicated holders are less likely to get bumped or jostled, compared to capped ‘normal’ pens stored in pen cups.

 

I have fountain pens that are stored nib-down in pen cups from time to time, and in general they don't leak. You can try it with a cheap Platinum Preppy pen; the model's Slip&Seal mechanism gives it an excellent cap seal, such that even ‘wet’ inks, runny inks, and inks that are apt to form ink crud will not be easily drawn from the converter on account of evaporation at the nib and feed. From the few models I've seen, desk pens usually have what are essentially slip-caps, and they tend to seal against ink evaporation reasonably well. (Platinum does have a model of desk pen that has the same design of gripping section, feed and nib as the Preppy, and the matching desk pen stand has the Slip&Seal mechanism built into the cups.

[loganrah]

I think Dill has hit the main point: desk pens don't get shaken around. Nor are they generally subject to large temperature or pressure changes.

 

Pens stored nib down shouldn't be leaking if they aren't being moved around or changing temperature.

[arcfide]

I've only seen an official recommendation for tip up storage of fountain pens from one major manufacturer that I can recall off the top of my head:

 

FAQ - Waterman

 

The justification in that space is that allowing the ink to migrate into the converter/cartridge will assist in keeping the ink fresh, rather than a concern for the ink dripping out. Most feed systems are designed to avoid ink dripping out of the pen if the tip is down, otherwise there might be issues with burping or ink spillage if you are writing quickly with the tip down under normal circumstances as well. 

 

It also took a while to find, but there's this page:

 

 

detail | プラチナ万年筆 (platinum-pen.co.jp)

 

This shows that the the slip and seal cap's published performance numbers depends on having a fresh ink cartridge installed and the pen laying on its side at room temperature. So at least Platinum considers resting the pen on its side as potentially "normative" in some respect. 

 

Modern pens generally have pretty good feeds, so having a pen cap down probably isn't going to cause too much trouble, but you will see more potential leakage than if the cap were pointing up. That's why the capless pens are all clipped to keep the nib pointing up. 

 

I've only had one pen that would "leak" when the nib was down, and that is my Pilot Falcon with customized Spencerian grind when using very surfactant heavy inks such as some Noodler's inks. In that case, I would literally have a drip of ink coming out of the pen when uncapped and facing downwards for too long. Changing the inks "fixed" the issue. 

[Bristol24]

This is good, practical discussion regarding fountain pen function and theory.  While I do not own a desk pen, I do have some experience in chasing down the unexpected and unexplained blot or even drip that can occur with some vintage fountain pens that are left filled and resting on their side indoors where temperature change is not an issue.  It happens most often with pens that are less than 100% full and is directly related to a significant change in barometric pressure such as occurs with an approaching storm.  Such a pen becomes a sort of messy barometer.  My guess is that there were desk pens "back in the day" that did this but it was just accepted as a periodic, albeit somewhat rare, annoyance.  In fact, other than a wetter than normal start or perhaps even a blot, it went unnoticed... until someone decided to clean the holder.

 

Cliff

[arcfide]

2 minutes ago, Bristol24 said:

My guess is that there were desk pens "back in the day" that did this but it was just accepted as a periodic, albeit somewhat rare, annoyance.  In fact, other than a wetter than normal start or perhaps even a blot, it went unnoticed... until someone decided to clean the holder.

 

People were much more tolerant of leaky fountain pens back in the day than they are now, especially with all the demonstrators out there.