In article ,
willshak wrote:

Anthony wrote the following:
I have this small slightly over 2' wall in bathroom of an older house.
I used my finder and got a reaction right almost in the center of that
wall. I then drilled a small hole to confirm it. I did hit something
and pulled the drill out. Now, my question is that i had to drill
almost 2'' before it made contact. Aren't studs suppose to be almost
flush against a drywall, with the exception of the depth of the
drywall?

In a 2' wide wall, there may not be any studs between the sides of the
wall (24" on center).
The bathroom wall cavity may be deeper than a standard 2" x 4" studded
wall.to allow a 4" drain/waste/vent to pass through. Possibly a 2" x 6"
studded wall
Both of the above may hint that what you finally hit 2" in was the
drain/waste/vent pipe. If so, I hope the hole drilled into this pipe was
above any fixture that drains into the pipe. Better a slight odor than a
leak.

Whenever I drill into a wall, I examine the evidence on the end of the
drill. Wood is a good sign. Metal, not so much.