Homebrew PCBs

I just ran a fresh test print through my HP Deskjet 340, with only Black #33, 
and the ink works if the board is perfectly clean. Where my fingerprints were 
on the board, the ink did not stick consistently. The Tarn-X did not work 
well, as it seemed to increase the fingerprints. Cleaning with a Schotchbrite 
pad gets the ink to stick more consistently, and with only about a minute of 
air drying, the ink was much harder to remove than the Tarn-X. I suspect this 
is due to the scrubber adding a little texture to the surface, allowing the 
ink to grab better. The ink would not simply rinse off, as it did with the 
Tarn-X. 

Scrubbed again with Scotchbrite, and applied a thin coat of DOT3 brake fluid, 
and all I get is puddling, and after 1 minute of air drying, absolutely no 
adhesion to the copper. (All ink rinsed right off). I am better off with a 
board that has been sitting around with nothing done to it. 

I did a fresh scrub with Scotchbrite on the same board, and my fine line test 
pattern seems to be holding. I am going to let this board dry overnight 
tonight, and If it stays good, I will test etch tonight. 

Here is my test pattern: http://i7.tinypic.com/20zsjeu.png

I don't know why all those white dots appeared when I uploaded it. On my last 
test print, I didn't scrub the top very well, so there are some problems in 
those areas. I will post final pictures after it has been etched.


On Tuesday 25 July 2006 12:22, Christopher Hart wrote:
> > Chris, have you ever looked at the ink used in the HP? how does it
> > compare to the MIS  or Epson ink as far as viscosity (flow
> > characteristics)? Is the inkjet head heated? What kind of cleaning cycle
> > does it use?
>
> I haven't actually seen the Epson or MIS inks to directly compare them. As
> far as I can tell, the HP inks are not heated, and the ink is only slightly
> thicker than water.
>
> Christopher Hart
> KC8UFV