Homebrew PCBs

Thomas P. Gootee wrote:
> 
> ------------------------------------
> 
> Alan,
> 
> Actually, the different paper types all work DIFFERENTLY, that way.
> 
> i.e. The JetPrint Photo Multiproject paper is ALWAYS that easy to remove, for
> me.  But the Staples Picture Paper is definitely NOT easy to remove (until
> now!).
> 

   Well the JetPrint does work very well even without multiple fusings with your 
webpages normal method, I did neglect to fill in that I have also modified other 
things.  I'm generally too impatient to see the outcome to allow it to soak 
well, so I changed other aspects to not need soak time.  In that case, even 
JetPrint leaves an annoying level of junk in parallel traces, TSOP pads, small 
holes, etc.  The extra fusings make it work great even without much soaking, I 
have my boards in etch within 5-10 minutes of printing and etched and starting 
soldering with 45 mins to an hour.  Even at that a bit longer soaking does make 
it a little easier, but almost always I just get too annoyed to wait.


> I have to use the Staples Picture Paper, instead of the much-easier-to-remove
> JetPrint paper, because, with my printer/toner combination (HP LJ4/HP toner),
> the Jetprint paper usually gets lots of pinholes in the large (and also often
> in the small) areas of toner, no matter what printer settings I use.

   Might want to keep an eye out for a HP 6L.  I've had great results with mine, 
the toner is different and seems generally easier to deal with than the LJ4 test 
prints I've done.  Can't really recall any pinholes, but as long as the board 
comes out usable with SMT with sharp trace edges I haven't searched too 
critically, so may have had one here or there.  Also to make sure we're 
comparing apples to apples, I'm using the Graphic Image Paper that has lees 
chance of pinholes but leaves more junk on the board not the Multi Project that 
has more chance of pinholes but leaves less on peel.  Just the GIP leaves almost 
nothing as well with multiple fusings, even with no soaking..

> 
> I will try the "multiple fusings" procedure again, with more than two passes
> this time, to see if that helps significantly, with my setup and the Staples
> paper.
> 

   I really just went to 3-4 fuses once I had the idea to do an extra just to 
make sure, may not be any improvement over 2 just takes little effort for 
another extra pass or two.  Again even that may not matter with a reasonable 
soak, I iron, run cold water for a min or two while forcing into the paper with 
my thumbs, and then start peeling.  Too damn impatient I know but it is working 
well enough for TSOP level parts for me.  Also seems to make the ironing phase 
less critical.  Caveat that my boards do tend to be 4"x3" or less and SMT, few 
large areas etc, so larger boards would likely take a bit more care even with 
what I'm doing.  But mine are relatively complex for the size with usually lots 
of traces in tight spacing, so a pretty good test of what's happening.

   Still haven't tried the Staples myself since I have plenty of JPP on hand and 
Staples is 30 miles away.  But from the general reports of a little more 
sticking I'd guess it has a higher moisture content in the coating to start, 
just a basic guess but the extra fusings should have an even greater improvement 
for it, so worth testing.