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Subject: [Homebrew_PCBs] picture of 6mil board & various things

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-04-13

again, sorry for messing up with the adresses and the flooding now...

last message..
ST


hi..

for those interested i have put a picture of a 6 mil board i just made on
<http://stud4.tuwien.ac.at/~e0225977/pcb.jpg>


the black particles you see is toner residue, i have only scraped it off
not cleaned
with paint thinner.
i find it quite easy and fast to just scrape if off with another bard, the
HP toner
is brittle enough to make this work.


you can also see a pinhole, which i regularly get with this printer.
normally i fill them with ohp pen, if i see them.

i also find the staedtler pen does not very well resist the cucl if it
gets older,
i wonder if there is a better solution.
my suspicion is that the layer gets thinner as the pen gets older and
dryer, but refilling
didn't change the effect. i hope they have not changed the recepie as some
old texts say.

i could reduce the spacing to about 10 mil, maybe 8 (with testing), but
there was plenty of space on this board.

I'm really satisfied now with the TT, and the etch (there is no gassing if
you don't have too much
H2O2, just keep it nice and green).


the main problem which really annoys me is the problems with the metric
spacing effects and
of course the pinholes which i just can't get rid of with that printer.
maybe thinner paper would
improove the situation a bit.


so now i am looking for a new printer. hopefully one that makes no
pinholes.
the bad thing with a new printer is that the toner is so expensive, 7 eur
for a genuine cartridge
at ebay for the IIID is hard to beat.


another big problem is doublesided boards. i try to avoid them but
sometimes there is no way.
the aligning is something i hate, and the fusing is also more difficult.
i think more practise would help with this.

I've made quite a few boards the last week, which allowed a steep learning
curve.
If you make only a board a month you forget what you have done the last
time until the next time.

I notice yahoo is slow again, damn it...
thanks for all the help...

ST