Enhance the effect of gall soap
To increase the effect of gall soap, you should apply gall soap on dry textiles.
For years I used gall soap, by always lubricating it on the previously wet-made textile ... Very often it worked hats. Here is an increase in effectiveness:
Leave the textile absolutely dry (!) After soiling - do not even put it under the faucet - and then treat the damp fabric spot with the moist (!) Gall soap: place the fabric in the dry sink, the gall soap under the running Moisten the faucet and rub it in the dry place. Then let dry over the clothesline (effect is amplified) and into the washing machine ...
