"Stephen" wrote in message
...
Hello,

I am thinking of making a book case or should I say shelf unit, as I
may use it for cds and dvds too.

Based on my experience of this house, the walls appear to be 8'x4'
plasterboard that is only supported by 1.5"x1.5" wood at the edges,
yes that's right, 4' centres! The plasterboard seems to be re enforced
by splashing some plaster on the inside of the wall and pressing
cardboard squares into it, to give the appearance of something
resembling an egg box with square holes.

As the studs are very insubstantial and few and far between, I don't
think screwing to the wall is a good idea. Though I could demolish and
rebuild the wall, I think a free standing unit might be a quicker and
cleaner way to do things.

If I use melamine faced chip because it's cheap and readily available,
unless you have a better idea?

What's the best way to fix the sides to the shelves? Would you just
butt them together or should I be routing/mitering bits out?

IIRC chipboard likes coarse screws like those used in plasterboard, so
I could just screw through the sides. I am not too worried about
having screws on show. I could always tidy them up with caps.

Or would you do something more elegant with hidden dowels?

Is there a magic method to make sure hole and shelf line up or is it
just a case of measuring twice, drilling once?

It sounds like you have one of the partition wall systems.
They are two sheets of board bonded together by a cardboard honeycomb.
They are very strong for what they are made from.
However books are heavy, you need to put the load down to the floor and just
fix it to the wall to stop it toppling if someone pulls on it.
Any of the standalone bookcases sold flat pack in B&Q, Ikea, etc. will do.
Just choose one with thick shelves so they don't bend.
A batten fixed to the top and into the wall should be enough to stop it
toppling and be invisible if you have a tall bookcase.

IME you won't get away with fixing cantilevered shelves to it and then
loading them with books whatever fixings you use.