--- In
Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett"
<cachureos@...> wrote:
SNIP
> at first thought seems to be a preparation fault, or handling
contamination.
>
> -make sure you don't touch the paper pre and post print.
> -ensure the board is absolutely clean, shiny and slightly scratched
before
> ironing on
> -once placed in the water, does the paper 'float off'? (at least,
almost)
> -do the 'lifted' traces remain on the paper?
>
Well, I think it might have been contamination prior to my getting the
boards. I bought them as leftovers from a local place I buy parts
from when I don't want to wait for delivery and they were extremely
beat up. I scrubbed them well and got them pretty clean with acetone
but the first board I etched must have had something I couldn't get
off because it was peppered with little copper spots which absolutely
refused to come off. I use latex gloves when handling the boards and
paper and only hold them by the edges, so I don't think I am
contaminating them.
I had somewhat better luck today using a fresh board from Radio Shack
and a different paper (Everyday HP Photo Paper, semi-gloss), but I
still had a couple spots where traces broke. Both spots the trace
was broken when I seperated the paper from the board, but I did not
see them on the paper. I left the board and paper in the hot water
bath long enough that when I lifted the board out the paper just slid
off and stayed in the water.
Both traces were easy to repair by soldering an old resistor lead
across the break, but I'd really like to get good enough with this to
not have this problem. I also notice that most of the traces have
lots of pinholes, enough that I use a continuity tester on all traces
just to be sure there are no gaps due to the pinholes. I've looked
at several images in this group and on the web and it looks like much
better results than I am getting are possible, and at much finer trace
widths.
I tried using a glossy magazine page but it jammed in my printer and
the paper I listed above jams about every other time, what kinds of
paper do you find works well? I'm using a Brother HL-2040.
Thanks!