I do this:
1 - Wash/clean with Comet powder then rinse with tap water
2 - Then wipe with Acetone
3 - Tonner transfer ... etch ... and so on
I do not use a kitchen scrubbing pad (the harsh ones) but a cooktop scrubbing pad. Same thing as the standard 3M kitchen scrubbing pads but not as abrasive so it does not scratch the copper at all when used with Comet. I found out that scratches are not helping at all with very thin traces (I speak 5 mils traces or 0.5mm pads for LQFP packages). You should find Commet at any grocery store
I found the second step to be absolutely essential. This forst cleans the board and second the acetone "remains" help the tonner to stick to the copper better. Be generous whit the acetone, use a kitchen paper towel and don't wipe the board dry, leave it air dry by itself (acetone evaporates almost instantaneous anyways). I usually do this right before "ironing". Bought my acetone from Home Depot or Lowes.
Then etch with the usual "pool etching solution". I am never going back to FeCl ... :))
I get consistent results each and every time. With a bit of care I was able to do 4 mill traces - 5 mil are already routine. My advice, don't skimp on buying a laminator - makes the difference. I got mine from here (
http://www.presentationsdirect.com/gbc-heatseal-9-creative-pouch-laminator.html) --- In Homebrew_PCBs@yahoogroups.com, "Frank P" <qz9090@...> wrote:
>
> There has been some discussion about removing toner from a PCB, but I was wondering what do you guys use to clean the copper clad before you iron-on your schematic to the copper?
>
> I suspect some of the answers might include the use of Scotch Brite (nylon scrubbing pad) and one the following:
>
> a) actone
> b) rubbing alcohol
> c) Tarn-x (not sure of the spelling)
>
> What works best for you?
>
> Thanks.
>
>
> Frank P.
>