Advertisements

Archive for September 10th, 2015

HP 7475A Plotter: Refilled Pen Performance

During this plot, an Inmac purple pen (in the Pen 5 slot) pretty much ran out of ink:

HP 7475A - Pen 5 before refill

HP 7475A – Pen 5 before refill

It printed the legend perfectly and started the trace solidly enough, proceeding upward from the far right, but after ten circuits around the center it returned dragging a very faint line behind it.

Ten drops = 0.05 ml of more-or-less reddish purple blended inkjet ink restored its good humor:

HP 7475A - Pen 5 after refill

HP 7475A – Pen 5 after refill

If you get ’em before they fossilize, they’re refillable!

Advertisements

,

5 Comments