I've got this hidden bookcase door that I need to stop

>>993181
>Inventor simulation of bookcase to illustrate sag

This might be the most autistic OP I've ever seen. I love it.

Below (or above) each shelf that sags, put a plate. Aluminum is probably enough, you could get thinner with steel, but even plastic might work.

Affix it in the corners or along the perimeter of the shelf.

If the edge always sags most, which it generally would, you can get by with just supporting the edges this way rather than covering the entire area. But for small materials, a hollow square/rectangle won't be much difference price-wise from a plate.

>>993181
Put a beam under each shelf anchored to each side.

>>993181
is this somthing you've built already and it's sagging? or are you just concerned from this model?
I doubt MDF would sag like that over those dimensions unless you are actually having this floating like a door, and there is no support from the ground.

in that case I'd suggest reconsidering having it floating, especially considering it's a hidden door, you want it looking as set-in-place as possible.


if you NEED it floating, it's probably going to need a stud up the left side all the way up the edge and an L shaped brace along the bottom.

I assume I'm looking at a cross section of wall, and the hidden cavity behind the unit? hinges along the right hand edge?

>1 mil of sag

You're fucked, OP, just give up.

>>993181
Can you just bend the hinges?

flip it upside down and wait for it to sag in the other direction