How to refurbish plotter pens?

[David Gesswein]

On Sat, Jan 28, 2017 at 03:51:49PM +0100, Mattis Lind wrote:
> I am about to get our IBM1627 (rebranded Calcomp 565) going but the pens in
> the case is quite dry. What is the best method to refurbish those? What is
> the best solvent to get the old ink out? What ink to refill with?
> 
> https://drive.google.com/open?id=0B-rp4vyPPYu1ZjVRbnlyczV4czQ
> 
That looks like the unpressurized ballpoint. I never tried to refill mine.
Another option is making replacements. I found current ballpoint 
refills and cut them down. I used a dremmel with cutoff disk. Watch for
splatters. I then stuck something in to remove 1/4" or so of the ink from
the end. Otherwise it will come out in the pen holder and make a mess.
The problem now is almost all refills use a larger diameter tip. I had to
look around some before I found the proper size. I did grind one larger
diameter one down by chucking it in a drill and grinding with the dremel.