Toner transfer is great until the boards becomes very dense and
detailed. For most 'hobby' boards- no problem. However, on a dense
board the success rate is 98% of image. That appears to be acceptable
for most people. I am perfecting a photomethod and can tell you that
the results are superior even on a kitchen table, I already made
tests to 9 mills on a dense board and am still pushing lower.
Costwise-of course photomethod will be a bit more expensive but the
quality and detail! Time: few minutes.
Mike
--- In
Homebrew_PCBs@yahoogroups.com, "grantfair2001"
<grant.fair@s...> wrote:
> Toner transfer is more appropriate for prototypes. Why? There are
> fewer steps with toner transfer - draw PCB art on computer, laser
> print it, iron on to PCB, remove paper, etch PCB.
>
> Silk screen is best for mass production. There are more steps:
obtain
> silk screen and frame, photosensitize the silk with emulsion, draw
PCB
> art on computer, print to transparency film, use that to expose the
> silkscreen, develop silkscreen, clean, then print PCB with silk
screen
> ink, dry ink, etch PCB, remove ink from etched PCB. Clean ink from
> silk screen (if you want to use it again!) soon after last print
made.
>
> The resolution attainable with silk screen depends on the "mesh" of
> the silk, that is (I think) the number of threads per inch of the
> fabric. I don't know the limits, but I think pretty good resolution
> is possible. I made some PCBs with silk screen 25 years ago; the
> technology was friendly, that is, with just simple instructions I
was
> able to make the PCB's without much trouble.
>
> More equipment is required to do silk screen - silk screen and
frames,
> work area for printing, some way to get the screens to hinge up, and
> some way to hold the pcb during printing, ink, squeegee, cleaning
> solvents, developer for photosensitive emulsion, the emulsion
itself,
> chemical to clean screen if you are going to reuse it. All you need
> for toner transfer is an iron and toner transfer paper, which may be
> simple paper of various kinds.
>
> There is at least one member on the list who used silk screen
> commercially, so if you have questions, he has the answers.
>
> Grant
>
> --- In Homebrew_PCBs@yahoogroups.com, Balan <balan3@y...> wrote:
> > Hi
> >
> > I am just learning the art of PCB making. Can Someone tell me is
it
> possible to transfer etch resist onto a board using Silk screen and
if
> possible what is the difference between toner transfer methord and
the
> silk screen.