Standardizing the Wetness of Pens

[tanburi]

Haecceities don't love standardization. I'll continue with the personalizing discourse about fountain pens, which just works.

[RitaCarbon]

The dimensions will probably be Volume/Area x length, which reduces to no dimensions nor units. It is a unitless, i.e. scalar, quantity.

 

How did you arrive that the dimension for wetness will be Volume/(Area x length)? area and length of what?

 

The first task is to define wetness. More wet = more ink output per given time?, keeping rest of the variables same? e.g. I remember a post where Binder draws a circle on a piece of paper towel, and the time taken to fill the circle with absorbed ink might give him a measure of wetness of the nib-feed-ink-paper combo.

 

 

Wetness = (Volume of ink)/(lenght of the line), where "length of the line" can be substituted by the amount of written pages.

 

If you start with the same amount of ink, than it is obvious that the more pages you write with it, the dryer the pen.

 

Such definition can be applied to a simplified model which does not take into account the size of the nib or other more detailed parameters.

[eric47]

Also, it is a trivial and very easy task to make a dry pen write wetter - a sharp craft knife and 10 seconds work with no nib expert being called upon (I have done this on several pens)

 

Craft knife, might scratch or damage the nib slit (and even the feed). Try softer brass sheets, which you can get in various thicknesses, instead.

Edited February 8, 2010 by eric47

[RitaCarbon]

NKK

 

I think you will be unable to do what you are setting out to do. I am an academic and scientist of 30 years experience and would have to say that there are too many variables you cannot consider in your formula which are specific to a user such as angle held (vertically), angle of rotation of the nib, user pressure, frequency of use of the pen etc.

 

Also, it is a trivial and very easy task to make a dry pen write wetter - a sharp craft knife and 10 seconds work with no nib expert being called upon (I have done this on several pens)

 

 

If you are are an acadameic scientist, you are probably familiar with scientific models. Scientific modeling applies a lot of simplifications which allow to reduce the number of parameters to a few most significant ones.

 

FGS, it's not a highly non-linear system, so I believe that the task can be accomplished to some degree of accuracy.

[RitaCarbon]

and find the change in weight of the paper

A little thing called evaporation is going to bedevil your efforts. If you weigh the pen on a milligram scale both after filling and after writing some standard length sufficient to consume approximately 0.5 ml of ink you will have enough resolution for your purposes.

 

Don't worry about such little things. Take the most important parameters and build a zero approximation of your model. Then you can improve it by adding some corrections. And don't let people who say "no" to stop you. You will always hear millions of "no" if you want to do something new in this world.

That's the nature of science to be surrounded by sceptics. It keeps you being challenged and objective.

Edited February 8, 2010 by RitaCarbon

[hari317]

 

If you start with the same amount of ink, than it is obvious that the more pages you write with it, the dryer the pen.

 

 

Ok, this will work for the same size of nib. so NKK was dividing this by the tipping surface area of the nib to normalize this figure.

[Eldan]

Don't worry about such little things. Take the most important parameters and build a zero approximation of your model. Then you can improve it by adding some corrections. And don't let people who say "no" to stop you. You will always hear millions of "no" if you want to do something new in this world.

That's the nature of science to be surrounded by sceptics. It keeps you being challenged and objective.

 

Was this absurdity directed at me?

[gyasko]

I recall an argument in a.c.p-p on a related theme: are wider tipped pens wetter in general? Anyway, the beauty of the "see how far it writes" strategy is that it simplifies the measurements.

[RitaCarbon]

Don't worry about such little things. Take the most important parameters and build a zero approximation of your model. Then you can improve it by adding some corrections. And don't let people who say "no" to stop you. You will always hear millions of "no" if you want to do something new in this world.

That's the nature of science to be surrounded by sceptics. It keeps you being challenged and objective.

 

Was this absurdity directed at me?

 

No, no, not at all. Please, don't take it personally. It's just a general statement.

 

I love your comments, BTW. You misread my note. It's all about that we need to be sceptical, but in the same way we have to proceed with our explorations no matter what. I am sorry if you took it personally.

[RitaCarbon]

If you start with the same amount of ink, than it is obvious that the more pages you write with it, the dryer the pen.

 

 

Ok, this will work for the same size of nib. so NKK was dividing this by the tipping surface area of the nib to normalize this figure.

 

Exactly! You can improve later your rough model by adding corrections for the nib size.

[Eldan]

No, no, not at all. Please, don't take it personally. It's just a general statement.

 

I love your comments, BTW. You misread my note. It's all about that we need to be sceptical, but in the same way we have to proceed with our explorations no matter what. I am sorry if you took it personally.

 

I don't think I misread it. I also don't think I took it personally. I was just wondering if you expected a response from me. You quoted my constructive advice and told the OP to ignore the "skeptics." You don't owe me an apology, but you might want to apologize to the OP for being patronizing.

[RitaCarbon]

No, no, not at all. Please, don't take it personally. It's just a general statement.

 

I love your comments, BTW. You misread my note. It's all about that we need to be sceptical, but in the same way we have to proceed with our explorations no matter what. I am sorry if you took it personally.

 

I don't think I misread it. I also don't think I took it personally. I was just wondering if you expected a response from me. You quoted my constructive advice and told the OP to ignore the "skeptics." You don't owe me an apology, but you might want to apologize to the OP for being patronizing.

 

My apologies to OP for being patronizing!

[bahnstormer]

Could you also calculate the distance a pen will write depending on its nib grade and wetness on a single fill of the standard convertor?? once youve worked out the first issues, this shouldnt be hard?

 

ie- "a Parker Sonnet with a grade B wetness medium size nib will write for xxx metres on a single fill of a standard Parker convertor"

 

that way we can also develop ink consumption figures for pens like we have fuel consumption figures for cars. then once you work out how much writing you do in a day or for a particular project you can work out which pen to use, without running out. or work it into the research when choosing a new pen.

 

i realise evaporation comes into it, but it should just be based on how far the pen will write when being used non-stop from full to empty.

[Eldan]

That would take more work and give a less accurate result than weighing the pen before and after writing some standard length. For one thing, "full" is not a constant; varying amounts of air remain in the converter. Also, in the interest of efficiency you should write as short a length as possible to achieve the desired precision. Evaporation from the pen is negligible over the duration of measurement, but evaporation from the written page is not. That's one reason why I suggested weighing the pen and not the paper.

[ruud2904]

@ NKK

 

Is there any progress or new insights to inform us about ?

[nkk]

Ok, no new progress as I was preoccupied during spring break and did not have time. I have sort of come up with a list of variables to test. A theoretical equation will follow a la Buckingham Pi Theorem. After than, variables will be systematically eliminated via experimentation. Right now I am sort of enrolling friends who may be interested to help me. More to come within the month. As always, comments are welcome. Just know that what is already in the thread is old, and I will update it in a week or two.

 

-Nkk