Hi Bert and Welcome!

I started dowsing about the same time as you. My Dad showed me how to locate underground pipes and cables using "L" rods. He called it "witching"

What method do you use to find depth of the water, coin, etc. when using the bobber, if I might ask?
Hello Rich:very happy to meet you my dowsing friend. I have 2 methods in finding the depth of water veins and coins. In finding the depth from ground level down to the water vein. I just ask what is the depth in feet from this spot at ground level down to the underground vein of flowing water? My wand or as some call it (bobber) will circle clockwise and then will go up and down which means waiting for instructions,I then say let each bob of this wand equal so many feet down (you can use any number of feet for each bob of the wand,if you think the underground vein of flowing water is very deep underground use a high number for each bob of the wand,in finding depth of coins instead of using feet use (inches)for each bob. The other way I just ask (Example) is the depth from this spot at ground level down to the water vein ( start with a low number) and when you reach the depth to the water vein the wand will circle clockwise which means yes this is the depth

Cheers,
Rich