Space Pen

A ball-point pen invented by American chemist, PaulFisher?, currently of Boulder City, Nevada.

I met him when I was living in Las Vegas. His factory is in Boulder City, Nevada, just up the road. I have a collection of his pens; in fact, I no longer buy any other kind. There are several styles, from the traditional "bullet" pen (which carries in one's trousers) to normal-looking retractables with pocket clips.

The secret, it turns out, is in the ink itself. It's actually closer to rubber than oil. The ball-and-sleeve is machined to absurd tolerances to achieve a shearing effect on the ink, which is then rolled onto the paper in much the same way oily inks are. The ink is too thick to work without the pressure, and the pressure without this viscosity simply results in a rapid oozing of the ink through the tip.

A secondary benefit of the denser ink is the life of the cartridge. I typically get more than a year (or two) from a medium point refill. The refills are packaged with an adaptor that makes it possible to use them in Parker pens.

I had one once and found it did ooze the ink through the tip resulting in slightly splodgy writing. the often told [but false] tale that NASA spent millions developing a pen to work in space while the russian just used pencils still amuses me. ObjectiveAdvantagesOfWoodenPencils

Over the last ten years I've had four faulty refills. They have always replaced them at no charge. I had one stop writing after nine months, two that leaked, and one that never wrote. They simply handed over a replacement.