Hey Chris,
Regarding the brake fluid, I seem to recall Volkan saying that he
made sure he wiped it ALL off so that it was dry again. You may
want to back up a few posts to verify that technique.
Either way, here is something else you can try for better adhesion.
Clean the PCB using acetone. Then, etch the board for a few
seconds, this should break up the surface a bit and allow for better
adhesion. The only reason I suspect this is because I had some PCB
material that simply would not accept toner transfer unless I did
that. I tried all the scrubing, sanding, polishing, washing, etc.,
the only way I got toner to stick was with a quick pre-etch. Might
work for ink too, you never know.
Chris
--- In
Homebrew_PCBs@yahoogroups.com, Christopher Hart
<tech_guru@...> wrote:
>
> 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
>