--- In
Homebrew_PCBs@yahoogroups.com, "Jackie Fetter" <lpt2@h...>
wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, "Phil" <phil1960us@y...>
wrote:
> >
> > a couple of questions:
> > - what is the width of the line produced by the fine point tip?
> > ultrafine?
>
> I get lines of 0.025" max. Thinner lines are possible with less
> pressure but 25 mill works fine for me.
>
>
>
> > - what are the wear characteristics? I assume the tip widens as
it
> > wears. The tips of sharpies I have used have also tended to
become
> > flexible over time.
>
> After a few dozen boards I notice little wear. Not cleaning the
board
> with steel wool before plotting would probably help by reducing
> friction. Any widening that occurs seems to be from the Pen Down
> impact. There is a lot of this when plotting text. The short answer
> is: I haven't had a problem; change the pen when it starts to wear.
> They're only a couple of dollars, US.
>
Instead of cleaning your board of with steel wool leave it tarnished
and then try plotting on it with the pen. Before etching it dip the
circuit board in warm to hot V-8 Juice. When I was a teenager I was
getting ready to make a wire wrap board up and had the Radio Shack
predrilled board and a glass of warm, just out of the can V-8 juice
sitting in the table beside it. My younger brother was horsing around
at the table and tipped over the glass spilling the V-8 juice on the
board. In a very short time that the juice was on the board it
cleaned it as well as if it was cleaned with steel wool. If you
remember the ads for V-8 juice in the '80s they use to have a person
hitting them self on the head and saying "I could have had a V-8". I
stopped drinking it after seeing that. >
>
> > - how is the ink different from the "office" grade sharpies?
>
> I went on at length in my original post about the ink
characteristics.
> It is totally resistant against ferric chloride and does not allow
> pitting like all the other pens I've tried.
>
> The ink was originally developed for marking laboratory glassware.
It
> was designed to remain on glassware through steam sterilization to
500
> F, resist acids, bases and many solvents.
>
> It does resist several solvents I've tried to use to strip the ink
> after etching. IPA, acetone, and ethyl acetate. Something more
> aggressive like MEK, Naphtha, or a solvent cocktail like "Goof Off"
> might work better but I stay away from the really nasty ones for
> health reasons. I just use super fine steel wool to take the ink
off.
>
>
>
> This is the perfect etch-resist pen. A quantum step above even the
> etch-resist pens sold by the DIY PCB companies.
>
> Might be interesting if the absorbent fiber ink tube in the pen
could
> have the ink squeezed out of it and use the ink in a standard
plotter
> pen or even better, inserted into a modified inkjet cartridge. I've
> noticed that when marking on glass the ink does not puddle up but
> stays put in a thin film.