1:1 on the vinegar to hydrogen peroxide.? The table salt is kind of trial and error, you want enough so you see bubbles coming off the copper.? With 120ml of solution this equates to the extremely scientific value of a few good shakes.? I found no discernible difference between cheap iodized table salt and fancy non iodized sea salt.? This method takes some time work.? I found it took 20-30 minutes to completely etch.? It helps if you agitate a little and wipe the sludge off the board with a foam brush.? The chemicals are cheap so use more than you think you need.? My first try I only used 60ml of total solution my little 50x50mm board.? It never completely etched and the mask failed.? I doubled it to 120ml total and it worked well.? I also found you can not reuse the solution but that my not be the case if you use a larger quantity per board.? I have never done this before so I can not compare it to using muriatic acid or commercial solutions.
I first found the method here ?
This is the lamintor I used for the transfer
