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View Full Version : which type of ink pen can work properly in zero gravity



suntrack2
2007-Oct-19, 01:25 PM
This type of problem may be faced by the astronots previously, when they started to take some notes in their note book etc. In my opinion the ball pen may be work in zero gravity if its both mouths are packed! or it is just difficult to analyse that which sort of ink pen or ball pen will be proper for use in the space ! ?

NEOWatcher
2007-Oct-19, 01:40 PM
This type of problem may be faced by the astronots previously, when they started to take some notes in their note book etc. In my opinion the ball pen may be work in zero gravity if its both mouths are packed! or it is just difficult to analyse that which sort of ink pen or ball pen will be proper for use in the space ! ?
One that has a pressurized ink cartridge.
Most notably, and all the rage during the apollo era (and might still be) is/was the "Fisher Space Pen" (Fischer?)

It's down to Earth selling point is that it writes upside-down.

Jason Thompson
2007-Oct-19, 01:59 PM
Actually a normal ball point pen will work perfectly fine in space. The ink is drawn through by its own cohesion, not by gravity. Gravity is more what stops the pen working upside down (by drawing the ink away from the nib end of the tube) than what makes it work the right way up.

NEOWatcher
2007-Oct-19, 02:07 PM
The ink is drawn through by its own cohesion, not by gravity.
Kind of a capillary type action? I can understand that. But I would think that as the ink is drawn out, that the consistancy would start to degrade.

Have they used regular pens?

Tucson_Tim
2007-Oct-19, 02:12 PM
This may be an urban myth but . . . didn't NASA spend a LOT of money trying to develop an ink pen that would be reliable in zero-G and the Russians solved the problem by just using pencils.

NEOWatcher
2007-Oct-19, 02:16 PM
This may be an urban myth but . . .
Yes, urban myth

didn't NASA spend a LOT of money trying to develop an ink pen that would be reliable in zero-G
No; fisher developed it (http://history.nasa.gov/spacepen.html) independently.

and the Russians solved the problem by just using pencils.
I read elsewhere here, that pencil shavings and dust will cause even more problems.

Tucson_Tim
2007-Oct-19, 02:20 PM
Yes, urban myth

No; fisher developed it (http://history.nasa.gov/spacepen.html) independently.

I read elsewhere here, that pencil shavings and dust will cause even more problems.

I seem to remember that during the Apollo-Soyuz rendevous, the astronauts noticed that the cosmonauts were using pencils.

NEOWatcher
2007-Oct-19, 02:23 PM
I seem to remember that during the Apollo-Soyuz rendevous, the astronauts noticed that the cosmonauts were using pencils.
I do see in the link I provided that the Russians used grease pencils. So; I guess there is a partial truth there.
It sounds like they already knew that graphite in the electronics would be a bad thing. (not hard to think of, but one of those simple things that could slip by)

Tucson_Tim
2007-Oct-19, 02:32 PM
It's an urban partial-myth.

suntrack2
2007-Oct-20, 10:25 AM
interesting, too much interesting, but how many astronomers do write in the space, are spending their hours in writing, or just pen brush is sufficient for them to chalk out their programs on computer screens only !!

:)

JohnD
2007-Oct-20, 10:29 PM
What sort of pencil?
Or did the Chief Designer also invent a Space Sharpener?

Can't see that the knife parings of normla pencil sharpening would be welcome in micro-gravity. Did the Russians use propelling pencils, which risk pieces of lead floating off - and graphite is electricly conductive!

John

Jason Thompson
2007-Oct-20, 11:52 PM
I would point out that pencil sharpeners enclosed in a plastic box to retain the shavings and graphite are common, so a similar device for use with pencils in space would not be overly complex.

mugaliens
2007-Oct-21, 04:43 PM
Ink smink.

Mechanical pencil!

Or electrons via laptop/keyboard.

JohnD
2007-Oct-22, 10:00 AM
I would point out that pencil sharpeners enclosed in a plastic box to retain the shavings and graphite are common, so a similar device for use with pencils in space would not be overly complex.

Jason,
An analogous situation is men's daily shave. I learn that on the Shuttle, males shave with razor, foam and a towel to catch the bristles. Some do use an electric razor, but that has to be adapted to connect it to a vacuum system to catch the bristles. The normal enclosure of an electric razor is clearly inadequte and I presume that an ordinaly pencil sharpener would be likewise.
Did the Russians bother with a vacuum attachement to their pencil sharpener, or just trust the seal on the box? Or use propelling pencils, which does risk a short length of lead breaking off, a common occurence and floating away? 3mm of lead would make an excellent bridge for any circuit.

John

NEOWatcher
2007-Oct-22, 12:49 PM
I thought that my link established that a normal graphite pencil was not used by the Russians, and the U.S. discontinued using pencils during Apollo. :think:
But; if that wasn't clear, here's a few comments.

An analogous situation is men's daily shave. I learn that on the Shuttle, males shave with razor, foam and a towel to catch the bristles.
Maybe now, but I would assume in the early days, when astronauts came back with stubble, they didn't have the elaborate vacuum assemblies.

Did the Russians bother with a vacuum attachement to their pencil sharpener, or just trust the seal on the box?
They used a grease pencil. Essentially a crayon. And adopted the Fisher pen in 1969.

Or use propelling pencils,
The U.S. used a mechanical pencil (I assume that's what a propelling pencil is) in the days before the Fisher pen.

Could it be done? Probably, but why even risk it?
Even a normal pencil, the tip can break off. So, even if you catch the shavings, either type of pencil has nearly the same issues.

And; why a pencil... The only advantage would require a vacuum eraser.

JohnD
2007-Oct-22, 03:56 PM
Neo,
A grease pencil.
Ok, no loose leads, but how do you sharpen a grease pencil?
I'm just interested, not challenging.
John

NEOWatcher
2007-Oct-22, 04:24 PM
Neo,
A grease pencil.
Ok, no loose leads, but how do you sharpen a grease pencil?
I'm just interested, not challenging.
John
You don't, its just as dull as it's thickness. Although, there is a coil of paper wrapping around it with a helix of a string to pull off the paper.
Are you old enough to remember transparency pencils?

suntrack2
2007-Oct-24, 11:05 AM
I don't know what impact goes on the substance of "led" in the space, since the most of pencils are of led, and led is toxic !!, Ya, or No !

NEOWatcher
2007-Oct-24, 11:51 AM
I don't know what impact goes on the substance of "led" in the space, since the most of pencils are of led, and led is toxic !!, Ya, or No !
No; Most pencils are a mixture of graphite and clay.
Early graphite pencils were made entirely with graphite, and pencils were expensive because of this.
Some Czech, discovered that mixing it with clay works just as well and considerably cheaper.
Maybe before this discovery, they used lead as an alternative to the graphite, but I really don't know.

JohnD
2007-Oct-24, 12:50 PM
You don't, its just as dull as it's thickness. Although, there is a coil of paper wrapping around it with a helix of a string to pull off the paper.
Are you old enough to remember transparency pencils?

Aaaaaaaaaaaaah,So!
Yes, I do! Or am!

Thanks, Neo!

John

Kaptain K
2007-Oct-24, 03:58 PM
Also note that metallic lead is fairly innocuous. It is in common use in solder, car batteries, wheel balance weights, fishing lures and sinkers.
It is lead compounds that are toxic!