Turn lock thrice

[Xinfu]

The lock of our door can be turn three times so that the bolt will go to the deepest part of the cave in the door frame; if I think it's too troublesome for other people to open it with their keys, what should I say to my brother?Can I say this?

-When you go out and lock the door, you just have to turn the lock once only. Don't turn it three times.

[Rusty]

The lock of our door can be turned three times so that the bolt will go to the deepest part of the hole/cavity in the door frame. If I think it's too troublesome for other people to open it with their keys, what should I say to my brother? Can I say this?

-When you go out and lock the door, you only/just have to turn the lock once only. Don't turn it three times.In your first sentence, 'can be turned three times' is commonly used in the US, where the British would prefer 'can be turned thrice' or 'can be thrice-turned'.
Saying "Don't turn it three times," in your last sentence, sounds great to my American English ears, but I wonder if a Brit would say "Don't turn it thrice."

[Xinfu]

Thank you~