BL a écrit :

virgiliopoeta wrote:

scottmandue wrote:

should fountain pens be stored with the tip up
between uses?

No. The ink dries in the feed and slowly clogs the
pen. It is better to store fountain pens in a
horizontal position or with the nib down.

This really doesn't make sense given that we live on a planet with
gravity. Stored nib up, ink will flow down and out of the feed and
into the reservoir. Stored nib down, ink will flow out of the
reservoir and into the feed (and in some unfortunate circumstances,
out through the feed and into the cap). If you store a filled pen nib
up and leave it unused long enough for ink to evaporate, not much will
be left in the feed to clog it. If, however, you store a filled pen on
its side, or nib down,
lots of ink will remain in the feed to clog it if left long enough for
the water in the ink to evaporate. The reason the OP noticed that the
pen he kept on its side wrote wetter than the one he keeps nib up
illustrates the effects of gravity on ink in a fountain pen. There is
nothing wrong with keeping a pen nib up between uses and most dealers
etc. actually recommend this (see below for just a couple of
examples):

http://www.cajunpen.com/html/fountainpen_hints.html

http://www.bertramsinkwell.com/penstuff.html

Pens are designed to be positioned nib up between uses. After all,
most have pocket clips or ring tops or are designed to be carried in
vest pockets nib up. Of course, the ink in any pen stored in any
position will evaporate eventually. If you have to keep a pen lying on
its side between uses (assuming between uses doesn't mean many days)
lest ink dry in the feed, there's probably something wrong the pen
(ill fitting cap, no or cracked inner cap, etc.). -- B

All of this sounds quite plausible, but has nothing to do with reality.
No theory however plausible is of any value if it does not explain
actual facts. It is incorrect to assert that modern pens are designed
to be stored nib up. In fact, most pens if stored nib up, will slowly
clog up even if tightly sealed. Certainly the great majority of pens if
left nib up, will not start at once, which is a sure sign of partial
clogging. Enough ink adheres to the feed to slowly clog it as
successive layers of dried ink accumulate. When you turn a pen nib up,
and leave it, not all the ink flows back into the bladder or reservoir.
A small part dries in the feed. This is the simplest explanation which
accounts for the observed facts, and is therefore most probably the
correct one.

If a pen is stored horizontally or with the nib down, on the other
hand, the feed is kept wet, and no ink can dry in the feed, which is
what normally causes clogging. Horizontal storage is somewhat
preferable to storage nib down, however, because ink leakage is less a
danger. In a well-designed feed however, even storage nib down is quite
safe.

There ishowever a tradition that pens should be stored nib up, which
apparently dates back to the days when non-stainless steel was used in
nibs. Stainless steel (most usually 18% chromium and 8% nickel) dates
of course only to the period 1903 to 1912, and was not commonly used in
nibs until after the First World War. Consequently, it was considered
more important to keep ink away from the nib, so as to avoid corrosion,
than to avoid clogging the feed. People simply were accustomed to
frequently soak their feeds for a few hours, which is much less harmful
to non-stainless steel than regular, prolonged exposure to ink/water.
For the same reason, gold was preferred to steel for nibs. Yellow brass
was also tried, and gave good service, but was finally rejected because
of the difficulty in rolling it into nibs. I have often wondered if
some metallurgist might someday obviate this difficulty. Yellow brass
closely mimics gold, and is much harder - similar in hardness to steel,
as I recall.

With modern stainless steel however, there is no logical reason ever to
store a pen with its nib up. If however you find a pen such as the
Sheaffer school pen, which seems to clog only very slowly when stored
nib up, you may wish to adopt this position.

All of this is however a bit of a tempest in a teapot, as it is not
difficult to unclog a feed by soaking overnight. Naturally for this
purpose alone one need not soak the whole pen.