Homebrew PCBs

I ran out of my office depot inkjet paper so I bought a box of Georgia
Pacific Image Plus+ Ink Jet (the redundant + is no typo) and gave it a
try for TT.  I was happy to see that it worked with my old process
(transfer, soak, rub).   In fact, it seemed to be letting go of the
toner pretty easily and leaving a lot less residue.  So, I tried an
experiment to see how little soaking I could get away with.  I briefly
wetted a fused board/paper assembly, wiped of the excess water and
then just pulled the paper off.  Lo and behold, it pulled free with no
residue in about 75% of the areas.  The paper clung in areas of denser
traces (like around surface mount ICs) and ground planes but even
those cleaned up quickly with a little rubbing.  I'd say it took about
5 minutes from wetting the board to being ready to dry for etching. 
Wow, that's an improvement.  By the way, there was very little toner
on the paper.  Much less than my previous paper.  

Interestingly, the areas that didn't peel all the way were where the
paper ripped because it was wet.  I was able to grab it and continue
the peel in a couple of places.  I'm going to try a dry peel.

One other process note.  When preparing the copper clad board for TT,
I just use 600 grit wet-or-dry sandpaper and wipe it down with acetone
on a paper towel.  No oven drying.  I've had zero problems with this
method.

Paper specifics:  Georgia-Pacific Image Plus+ Ink Jet Paper.  94
brightness 24 lb weight.  $18 for 5 reams (2500 sheets, all together)
at Sam's Club. Yes, that less than 3/4 of a penny per sheet.  I added
it to the database.

I just uploaded 2 pictures in files/toner_transfer/   - TT-1.jpg and
TT-2.jpg

These are 10X microscope pictures of a TT board with the paper I
reported on.  Dry peel didn't work so I tried a "moist" peel of the
paper.  I let the board paper assembly cool down, sprinkled water on
the paper, wiped it off with my hand and then pulled the paper off. 
The 2 pictures are of the transfered toner with no clean-up.  TT-1
shows a SOIC16 pad and traces. Most of the traces are 12 mil with a
few 16 mil ones as well.  You can see some paper residue but its
pretty clean.  In addition, the whole board was perfect - all the
toner transfered.  TT-2 shows a 3 mil border I use as part of
panelizing.   

Larger areas of toner don't let go of the paper very well, though.

--- In Homebrew_PCBs@yahoogroups.com, "Phil" <phil1960us@y...> wrote:

> I ran out of my office depot inkjet paper so I bought a box of Georgia
> Pacific Image Plus+ Ink Jet (the redundant + is no typo) and gave it a
> try for TT.  I was happy to see that it worked with my old process
> (transfer, soak, rub).   In fact, it seemed to be letting go of the
> toner pretty easily and leaving a lot less residue.  So, I tried an
> experiment to see how little soaking I could get away with.  I briefly
> wetted a fused board/paper assembly, wiped of the excess water and
> then just pulled the paper off.  Lo and behold, it pulled free with no
> residue in about 75% of the areas.  The paper clung in areas of denser
> traces (like around surface mount ICs) and ground planes but even
> those cleaned up quickly with a little rubbing.  I'd say it took about
> 5 minutes from wetting the board to being ready to dry for etching. 
> Wow, that's an improvement.  By the way, there was very little toner
> on the paper.  Much less than my previous paper.  
> 
> Interestingly, the areas that didn't peel all the way were where the
> paper ripped because it was wet.  I was able to grab it and continue
> the peel in a couple of places.  I'm going to try a dry peel.
> 
> One other process note.  When preparing the copper clad board for TT,
> I just use 600 grit wet-or-dry sandpaper and wipe it down with acetone
> on a paper towel.  No oven drying.  I've had zero problems with this
> method.
> 
> Paper specifics:  Georgia-Pacific Image Plus+ Ink Jet Paper.  94
> brightness 24 lb weight.  $18 for 5 reams (2500 sheets, all together)
> at Sam's Club. Yes, that less than 3/4 of a penny per sheet.  I added
> it to the database.