Spot the ball... er Stud - for ventilator through wall

[RichardL]

Studwork wall
Pictured is the corner of my bathroom conversion - Timber/stud work build room.

 

Orange - roughly where a 100mm through hole required for a ventilator.

Green - known vertical stud position - screws/nails found with a magnet.

No other obvious nail/fixing lines.

I'm not going up and through the eaves on this room.

 

The challenge.
I'm betting theres a diagonal stud in there somewhere & ideally would like to miss it when I drill the 100mm hole.

I guess I could hedge my bets - its either floor to ceiling or mid way to ceiling - if I draw both crosses I might miss it?

and/or some pilot holes to check there's void before the big hole?

and/or toss a coin a few times and wait until I'm on a lucky streak?

Question
Are there any better methods?


Cheers

[Big Jimbo]

I'd go with a good few pilot holes. Middle, Top,Right, Bottom, and left. You can easily fill them if it don't work out.

[TonyT]

Cut the plasterboard out first and see

[Bonner]

As above, either lots of exploratory holes or a neat cut out of the PB

[RichardL]

Thanks