Did a few experiments over the weekend.
I sanded all boards in this experiment with 400 grit paper with random
orbital sander.
Instead of acetone I used lacquer thinner.
Label on lacquer thinner shows
these components
methyl
alcohol, toluene, acetone, ethyl acetate, xylene, methyl ethyl ketone, ethyl
benzene, petroleum distillates.
The alcohol I used is fuel grade, percent not listed on can.
I tried the mix suggested in another post, 2 parts alcohol 1 part lacquer
thinner.
With cheap 20# copy paper the transfer was very bad,
most toner fell off or pealed off with the paper.
With Hammer mill color laser gloss had excellent
transfer but the small holes in via’s partly closed, bleed.
I thinned the mix a bit more 3 parts alcohol 1 part lacquer thinner.
Even worse results with copy paper.
With color laser gloss got near perfect transfer, at
least as good or better than with my laminator, via’s stayed open,
perfect.
I also tried boards pretreated with lacquer thinner, to form the oxide
layer, and not treated. The treated boards seem to do a slightly better but not
much.
I also notice that by setting the paper type to photo or gloss, and setting
the gloss level to best, seemed to put more toner on the paper an got better
transfer.
I did not so to speak, burnish the boards, but just applied a moderate
amount of pressure with the folded up edge of the paper towel used to blot the
board. I was worried that too much pressure might smear or widen the small
traces.
I did a double side board, two 1/16 boards, using the 3 to 1 mix, color
laser gloss paper, and got boards as good as any I have ever done with my
laminator. Lost one trace right on the edge of the board, think it may have been
where I picked up the board with fingers. All the traces down to 0.012 are
perfect, even the feed thru between .1 headers where perfect. I struggled with
my laminator for a year before I got boards this good! I could even use a
non-woven abrasive pad, I use the white ones with no actual abrasive, to clean
off the remaining paper, there is very little paper residue left anyway, much
less that with my laminator.
One trick I use for patching toner that did not transfer. Use an ultra fine
sharpie, and draw in the missing section of the trace.Go over a couple times,
let it dry in-between passes. If you limit coffee input you can even touch up
.012 traces.
RD