I've had 100% success with this process even with very tarnished boards:
1, Clean with Tarn-X
2. Scrub, both directions,under water, with 400 grit wet or dry paper.
3. Dry with cotton cloth (diaper).
4. Wipe with cotton swab damp with lacquer thinner.
5. Dry with cotton cloth (diaper).
6. Apply toner transfer paper.
--- In Homebrew_PCBs@yahoogroups.com, Wayne Topa <linuxone@...> wrote:
>
> I have followed the suggestions of those more experienced then me in
> precleaning the pcb, and found that I 'must have' been doing
> something wrong.
>
> My first 2 boards were cleaned using the scotch brite pad and dish
> detergent and failed when I ran the board through the laminator.
> By failed, I mean the toner did not adhere to the board. I had to
> repeat the cleaning/transfer 3-4 times before I got good adhesion.
> Wasted a lot of TTS paper that way.
>
> I recently ordered some pcb's from abcfab, and on on the EBay page
> describing the boards, Bill mentioned that there were a number of
> cleaning solutions that would clean the copper, and that the
> scotch brite scrub wasn't necessary.
>
> One of the cleaners mentioned was Tarn-X. I went out and bought a
> new bottle (the bottle we had must have been 5-6 years old) and
> tried it on 4 boards last night. I pre-washed the boards with soap
> and water using a cotton ball, dried with a paper towel then using a
> cotton ball soaked with Tarn-X , simply applied it to the the boards.
> I then washed off the boards with water only and dried them,
laminated
> them and after 5-6 passes through the laminator I dropped
> the boards into cold tap water and, in 2-3 minutes, the paper floated
> off and there was no toner on the carrier at all (I use Pulsar TTS)
> and the boards were perfect. I had a hard time believing it could
> be that easy.
>
> The boards from abcfab were not tarnished in any way so this may be
> why this worked so well. Even so I did see a change in the color of
> the copper as I applied the Tarn-X. I am so pleased with the
> results, I though I better pass it on.
>
> This Pulsar TTS paper, though somewhat expensive, is a dream to work
> with. The paper floats off and does not require any work at all. I
> have tried other medium but it is just too much work getting the
> paper layers off the toner. As I am only making boards for my own
> use, I find the Pulsar TTS is the way to go. Using the Pulsar, 1
> minute etch method, I can go from printer to finished board in about
> 15-20 minutes.
>
> Good Transferring!
>
> Wayne
>