On Mon, 27 Jan 2020 14:50:45 -0800, Jeff Liebermann
wrote:

On Mon, 27 Jan 2020 10:52:14 -0800, Jeff Liebermann
wrote:

Mo
https://www.metcheck.co.uk/collections/barograph-pens-and-ink
http://www.fountainpennetwork.com/forum/topic/47798-chart-recorder-ink-options/
https://www.ebay.com/itm/Barograph-Thermograph-Recording-Ink-Slow-Dry-Dark-Blue-5oz-15ml-/123902459872
https://www.worthpoint.com/worthopedia/barograph-instrument-recording-pen-276775650
etc...

More of the same:
https://www.ebay.com/sch/i.html?_nkw=recording+instrument+ink
https://www.ebay.com/sch/i.html?_nkw=barograph+recording+ink+slow+dry
https://www.ebay.com/itm/ink-Universal-Bristols-Recorder-Ink-Waterbury-CT-Recording-Instrument-Ink/392645088431

One mo
https://www.ebay.com/itm/Barograph-or-Instrument-recording-pen-for-use-with-ink/143313378165
Note the comment on felt tip pens causing pen drag and slowing
response time.

To make a slow dry ink, I would guess that the ink should be high
viscosity so that it doesn't drip or run. It should also be high
surface tension to slow evaporation. The high surface tension is easy
enough by adding a few drops of a wetting agent such as Kodak Photo
Flo 200:
https://www.bhphotovideo.com/c/product/28195-REG/Kodak_1464510_Photo_Flo_200_Solution.html
I don't know how to increase viscosity. Maybe add some more pigment
or solids.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558