Use 'knock together' when something is made quickly, without much preparation or detail.

Speed Emphasized

'Knock together' is casual language, suitable for everyday conversation but not for formal writing.

Informal Situations

Indicates a solution or creation may be makeshift or temporary, not permanent.

'Knock together' can describe items hitting each other, creating a noticeable sound.

Often refers to objects accidentally hitting each other, not deliberately.

Use when illustrating the physical interaction between two or more objects.