The arrival of a Fountain Pen Day purchase made me think about one thing I always do with a new pen or converter. It is also something you still see posted as a possible fix for the lack of ink flow with a new pen. While many of you will already follow this process, there are those of you new to the hobby who may not. As the title says, this is flushing the new fountain pen with water.
So why do we do this. Basically there is always the chance of very fine manufacturing dust/debris/detritus remaining in the pen. It is not as if the makers, be it the single person or large company do not try to avoid this, but even with washing and pressure blowing air through the components, there is still a chance of a little bit remaining. I would suggest the main area where the bits remain or collect is in the feed.
Do pen companies admit to this? Yes they do, but let’s be honest how many of us read the accompanying printed material, after all we just want to get on with using our new pens, however if you look at the care guides you will normally see a recommendation to first flush the pen.
So do I have any tips or tricks? Well personally I find it easier to clean out cartridge converter pens than piston and vacuum filler ones, the reason being you can remove the section and flush water through from the inside. Additionally I remove the converter, which will be rinsed by filling and emptying with water.
With the section, where possible, I will fill a converter (or use a syringe bulb) then push water through the back of the nib unit. Note I do not draw water in through the nib as the idea is to expel any dust not pull it further in to the pen.
When I can’t remove the section then I just repeatedly draw water in to the pen then empty it out again.
Note I just use tap water, not distilled, and I see no reason why to add soap, washing up liquid, or pen cleaning solutions. It is not dried ink or ink residue we are trying to remove, though it can be manufacturing oil residue.
Does this always work? Most the time it is actually not needed, but it is good practice. There are rare times though when it will not. Some times there are bits of fluff or dust in the tines and careful flossing will fix this (though you do need to be careful as you probably do not want to widen the gap). Some times (and this is even rarer) it might be the channel in the feed has not been cut properly (ebonite) or the flashing has not been properly removed (plastic, acrylic, 3-D printed, etc).
So is there ever a time I do not flush a new pen. No. Not even when I am in a rush to use a long anticipated purchase such as my Hakase. Now regularly cleaning pens, that is a different matter (and laziness there has cost me).
dapprman 
Good post, one I do not follow nearly as well or often as I should. I get overly excited about that purchase and if I flush the pen it usually means drawling water in through the nib opposed to expelling it.
I do the first flush with a mild / dilute ‘Fairy Liquid’ solution followed by clear (tap) water a few times. So far, so good…
I don’t flush new pens at all. First ink is always Waterman though and that seems to do the trick just as well.
I’m in favor of a little bit of some kind of cleanser in the water I’m using to flush out a new pen. The reason being that water alone doesn’t remove oil very well, should there be any. Especially a cool temperature water, cool enough to get your hands in without burning. A mild cleanser, such as Dawn, can get under oil so it can float out with the water. Also, my experience is that some little bits of debris wedged into corners or caught on an imperfect edge will more readily relinquish their hold with the surfactant in cleaners such as Dawn or pen flush. I usually go for the Dawn – not much is needed, and it’s cheaper.
We’re fortunate in the UK that we can use virtually any dish soap, though Dawn is a common one here under the name Fairy Liquid.
Fairy Liquid? Really? Here in the US, Dawn is considered to have a somewhat better formulation, but perhaps that’s just their hype. Dawn makes commercials here about its use when oil spills were being cleaned up. They used Dawn to take the crude oil out of the feathers and fur of affected wildlife. “Gentle but strong.” Anyway, I just had to respond again because… Fairy Liquid?!
It’s an old brand (Fairy) though looking on line Proctor and Gamble bought them way back in 1927 and effectively over time the product become the same, or at least very similar. I believe Dawn is considered a lot gentler than other common washing up liquids in the USA so may well have been a US release of the British product under a name more suitable for your market.