How do I make floating weapons?

I'm assuming you're going for a sig picture. So, do it like this: First, place a couple walls down. Then, put your weapons down on them. Lastly, delete the walls, and they should stay. Touch the weapons, however, and they fall.

 

To add on, you cannot save them floating in the air. It must be done in a round of Forge.

 

Yes, dont delete the walls and then save. Make sure to save before the walls are deleted.