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.