Are there ways I can stop a long bookshelf from sagging?

[Phil Pascoe]

:lol: AndyT - I wasn't being serious, but thanks for the info. (I actually have a newer Larousse as well - well, two actually )

 

[AndyT]

:lol: AndyT - I wasn't being serious, but thanks for the info. (I actually have a newer Larousse as well - well, two actually )

I was being flippant as well - we seem to have run out of bookcase sized spaces in our house and the ones we have are all full!

 

[DTR]

A bit off topic, but what about the carcass sides? If the shelves span the full width (whatever way they're constructed), what is the best way to build the carcass in order to take the weight?

 

[RobinBHM]

If I was making them, I would probably build a face frame with sides of 18mm mdf or birch ply flush to the inside of the frame. A face frame with 50 x 25mm jambs and 80mm x 25mm rails works well. Skirting/plinth can then be face fitted leaving 30mm or so of the face frame showing. Same can apply for a cornice.


If you are screwing the carcase you may want to run the bottom through so the sides sit on the carcase base. There's then no issue with the bottom screws being in shear. That only works if the unit can be assembled lying down and then lifted up without clouting the ceiling (did that once with a wardrobe D'oh!).

 

[Benchwayze]

If you want to go fancy, make some vertical supports, every couple of feet. Round off the fronts, and glue some old book dust covers onto them. (If you have a PC scanner, this is a doddle, but do remember which are the real books.)

HTH

John

 

[partsandlabour]

Torsion box as others have mentioned is the way to go. But keep the thickness of the ply down on the top and bottom, say 6mm birch ply - better to use the thickness of the shelf for the frame - this is what will give you the stiffness when making a torsion box.

I've used 18mm birch ply on edge for the frame in the past.

Torsion, torsion torsion!

 

[Benchwayze]

Just make a series of boxes, (I think the term is modular.) to the dimensions you need for your collection of books. Stack the boxes as you wish. You won't get any sagging if you stay within the prescribed limits of length, for the thickness of material. You will have a similar effect to a 'torsion' box. The only disadvantage is the space taken up by the vertical ends to each box.
if the length of your boxes stipulate say 1" thickness, then use 1/2" material, so that the top and bottom of a pair of boxes equals 1".

HTH