No problem ever for me with wooden shenhao 5x7 or metal linhof 4x5.
But, then again, what do you look like!? I am on the dark side and could be mistaken as "middle eastern" and always seem to get the bomb frisking treatment. My pale, re-headed wife is never bothered! My observation is Asian tourists seem to get their bags searched more thoroughly because of the temptation to bring in favourite food items and disregarding the warnings. You may be better off to declare a "finished wooden camera" on your customs form to avoid any doubt or suspicion. Singapore is lower on the list of likely countries from which drugs could be imported.
Hope you have a great trip.