To duplicate items with defined spacing, follow these steps:
- Place the first item on a shelf and duplicate it with the shortcut [D].
- Then, define the spacing between these 2 items by moving the second one. For precision, use the left and right arrows on your keyboard.
- Once you find the right spacing between these two, duplicate the second one with the same spacing with this keyboard shortcut: [ctrl] + [alt] + [right arrow] or [ctrl] + [alt] + [left arrow].