45g Electroless Copper Tinning PCB Tin Plating Crystals Immersion Preparation

I bought this to tin some PCBs that I wouldn't be soldering for a while and it did an amazing job. Once made up it keeps for much longer than it says on the packet. Preparation is everything - the better you clean your copper the better finish this stuff leaves. Instructions are in English and Polish.

I had already tried this product with less than great results a couple of years ago but was in need of a solution in a hurry so thought I'd risk it again. Mistake.Clumpy crystals dissolved in de-ionised water >80C as per instructions and left to cool (constantly stirred) making a milky white solution. PCB meticulously cleaned and placed into solution at around 27C. Unless constantly agitated / stirred solution separates quickly. Stirring for about 15 minutes and leaving it alone for another ten, I returned to an almost clear liquid with white sediment at bottom and all over board. Retrieving board and rinsing as per instructions, I had a dull grey finish over most of the board. However this was easily removed by simply rubbing with a paper towel....Not recommended in my opinion.

Impressed that it protects the copper from oxidation.