Shelf construction // price advice

[will_s87]

Hi, I know this has been covered before but I was hoping you could give me some advice;

Making a built in bookcase to fit the alcove between chimney breast and wall.
Span 1200mm.

Sagulator Inputs

Span = 1200mm
depth = 300mm
shelf thickness = 27mm (sandwich: 9mm ply / 9mm pine strips / 9mm ply top) E2A: (6mm ply // 15mm pine // 6mm ply) - for price this seems like a better option.
distributed load = 30kg

0.5mm sag total.

I was going to glue the shelf supports in as I add the shelves. working from bottom to top.

IS there a cheaper / quicker way to make the shelves? ( I suppose those options are mutually exclusive)

If I go down the sandwich glue up path, any advise on keeping the 3 pieces aligned whilst I'm struggling to clamp them?


thanks,
Will .

 

[deema]

I would make them out of 18mm ply assuming your looking for the ply edge finish. Along the back I would glue / screw (which ever you like, screw up from underneath) a strengthening strip. It could be a 50mm wide stip of 18mm ply, or something else a little thicker such as a standard 25 by 50mm battern. This will form an L Shape which provides rigidity from droop and with it being at the back won't make the shelves look thick and 'clumsy'. The battern at the back won't be noticed. You can make it sculptured to add interest / make it into a feature.

 

[Phil Pascoe]

Two x 18mm ? Not so difficult to glue up as three layers.

 

[RobinBHM]

Solid 24mm pine panel is an option, not sure of sag though

http://www.ebay.co.uk/itm/Pine-Panels-S ... FFMfVA-sZg

If you are assembling first then installing, I would screw shelves in place. Or screw top and bottom then drill for shelf pins.

Fittings shelves with spacers in between is a good idea for load, but in practice is difficult unless you have sash clamps to pull up tight.

If the bookcase goes down to floor, you could make a sub base, comprising of a ply or mdf board sitting on some plinth feet. Put in place first, level up, sit assembled bookcase on, then pin on a plinth to hide. Works extremely well for wardrobes.