On Thu, 16 May 2019 19:27:29 +0100, Rod Speed wrote:

Commander Kinsey wrote

I've put up my own shelves with proper brackets. But I see these
"floating shelves" advertised. I thought, "What's holding them up?"

There is usually rods that go into the wall. Can be a bit fiddly to
get them in the right place so they slide into the shelf properly.

Apparently there's no right angle involved, just a screw
going straight into the back of the shelf out of the wall.
How can that possibly support anything?

It's a decent sized pair of rods that stick out of the wall
that slide into holes in the shelves with most of them.

But proper shelves have an angled bracket which can hold a lot of weight. Nothing without a 45 degree support can hold weight. Just try holding a car battery at arms length. Now support your arm at your elbow by using the other arm at 45 degrees.