Homebrew PCBs

Last night I was working on a double sided board and I have some 
traces that are 8mil apart. I too was having a problem with getting 
the paper out in between the traces and didn't want to rub too hard 
for fear of ripping up the toner. I let it soak in warm soapy water 
for about 1/2 hour and then used a pencil eraser (on the end of a #2 
lead pencil) and rubbed where it wasn't comming off. To my surprise 
it works like a champ. It takes the paper right off and does no harm 
to the traces. I did notice though that you HAVE TO DO IT while its 
wet. If you try doing it when its dry it will mess up the toner. I 
was even able to get the paper out in the drill holes. I usually 
just let them go and etch as is. But I looked at the board under a 
magnifying glass and its perfect!! No problems with the traces at 
all and no paper! Try it out and let me know how it works for you.




--- In Homebrew_PCBs@yahoogroups.com, "gettingalongwouldbenice" 
<gettingalongwouldbenice@y...> wrote:
> 
> I've done some more ironing experiments.  The toner is sticking to 
the
> board very well in most areas.  With a little practice, it should 
be
> fine.  Problem is that I can't get the paper off without tearing 
off
> the traces.  I've got a TQFP64 package with a bunch of parallel 
runs
> with 5 mils between them.  The toner looks fine, but the paper is
> stuck in the spaces between runs.  I soaked it for an hour, but 
can't
> get the paper out of the cracks without tearing off the runs.
> Larger traces with more space are no problem.
> Suggestions?
> 
> Also, what do people use to touch up missing trace segments, 
pinholes,
> etc.???  Lumocolor 313-2 would do it except that the pen tip is way
> too large.  If I could find a pen that would do the touch up, I'd 
just
> plot with the pen and be done with it.
> 
> What I need is a finepoint system 0.1 pen with etch resistant ink.
> 
> How do the various etchants affect different inks?  I've only used
> FeCl.  Are other etchants easier on the resist?
> 
> Thanks, mike