Mirj -- good idea to publish this "recipe". It is effective, I have used this mixture many occasions. Here's another choice for you: I'd already attempted this remedy on the REALLY bad grease clog, with no success. My grand daddy just became of call in those days, and that i --- well, I whined to him. He explained what he i did so as he was the manager/fix-it guy for any trailer park: escape your handheld blow-dryer. Make certain there's no water on the ground where you are standing which means you will not electrocute yourself, then open the accessibility drain pipe - that little trap thingy. Aim the new air directly on that, and it'll melt the grease and let everything slide on through. My Grand daddy Rocks!
This really did work! It foamed a great deal initially. I believe the secret ended up being to carry on doing it. After trying this, I looked up, which is also suggested as periodic maintenence procedure. Just flush your drains with vinegar and sodium bicarbonate from time to time, like all month approximately, also it have them obvious and fresh - so you do not get a clog problem!
This is effective being an oven cleaner.