Background Condo/Apt building (28? floors) Built 1993 Seattle, WA Wall facing neighbor's wall
Need to drill into stud to mount Murphy bed.
I drilled into same area that were used for the old Murphy bed (3" screws minus 3/4" from thickness of bed frame), but hit METAL
Metal runs vertical floor to ceiling Runs ~16" apart horizontally Tried about 5 spots - all hit metal
Originally, I use the old school finger tap method that always worked in the past, but then hit metal 2x
Bought magnet stud finder and confirmed using that it runs vertical
Also bought Zircon e50 (http://smile.amazon.com/Zircon-StudSensor-e50-Electronic-Finder/dp/B002R5AVVY/ref=sr_1_2?ie=UTF8&qid=1454125433&sr=8-2&keywords=Zircon+StudSensor+e50+Electronic+Stud+Finder) that supposedly detects electrical outlet. Tested it around plug and it did detect from there. No electrical warning where I drilled, so I used a small bit and drilled through, hoping it was a plate over wood. Nope, drilled through to emptiness.
Zircon stud finder suggests stud is about 4" wide, with the magnetic stud finder sticking right in the middle. Interestingly, magnetic stud finder is not sticking to where I drilled into metal.
So, any ideas?
Metal studs? Pipes (nothing leaking AFAIK - liquid or gas)?
Sorry if this is a repeated question. I did search but didn't find an exact match to this question.
Thank you for your time and advice! (I REALLY don't want the murphy bed slamming shut on me, esp if "with a guest"!)